I am looking for a .308 battle rifle that is reliable and can easily accept optics (ACOG). I'd like something more "old school" such as the M1A or the FAL, however these don't accept optics as well. This lead me to AR-10 type rifles. I want a 16-18 HBAR type barrel. I like the LAR-8 because it accepts the FAL magazines which can save me some cash. Anybody have any input on these as compared to the DPMS or Armalite variants?
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Any user input from RRA LAR-8?
- Thread starter Oguruma
- Start date
Re: Any user input from RRA LAR-8?
Pmags are cheaper than surplus FAL mags and work with the bolt catch, you should take a closer look at the LR-308 pattern rifles...
eta: I see you are in Germany, FAL mags might be cheaper over there and more avaliable..stateside the pmags are less than $20 each.
Pmags are cheaper than surplus FAL mags and work with the bolt catch, you should take a closer look at the LR-308 pattern rifles...
eta: I see you are in Germany, FAL mags might be cheaper over there and more avaliable..stateside the pmags are less than $20 each.
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oguruma</div><div class="ubbcode-body">I am looking for a .308 battle rifle that is reliable and can easily accept optics (ACOG). I'd like something more "old school" such as the M1A or the FAL, however these don't accept optics as well. This lead me to AR-10 type rifles. I want a 16-18 HBAR type barrel. I like the LAR-8 because it accepts the FAL magazines which can save me some cash. Anybody have any input on these as compared to the DPMS or Armalite variants? </div></div>
I have a 16" LAR-8 and love it. I have shot a few hundred rounds of factory ammo from 150gr Federal Power-Shok to 168gr Federal GMM. Never shot any milsurp stuff. It shoots them all very well and I've never had a FTF/FTE or any other issues with the bolt holding open. The only magazine I currently have is the rebuilt surplus mag that RRA supplies with the rifle.
I have also heard the Thermold/RRA polymer mags are working excellent and they are around $20 US. The only consistent complaint you hear about the LAR-8 is magazines. It's rarely an accuracy or reliability problem. Since the magazines appear to be an issue of the past, the LAR-8 is a viable option.
I have never shot an AR-10 or DPMS. At this point in time, I have no desire to look any further than my LAR-8.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oguruma</div><div class="ubbcode-body">I am looking for a .308 battle rifle that is reliable and can easily accept optics (ACOG). I'd like something more "old school" such as the M1A or the FAL, however these don't accept optics as well. This lead me to AR-10 type rifles. I want a 16-18 HBAR type barrel. I like the LAR-8 because it accepts the FAL magazines which can save me some cash. Anybody have any input on these as compared to the DPMS or Armalite variants? </div></div>
I have a 16" LAR-8 and love it. I have shot a few hundred rounds of factory ammo from 150gr Federal Power-Shok to 168gr Federal GMM. Never shot any milsurp stuff. It shoots them all very well and I've never had a FTF/FTE or any other issues with the bolt holding open. The only magazine I currently have is the rebuilt surplus mag that RRA supplies with the rifle.
I have also heard the Thermold/RRA polymer mags are working excellent and they are around $20 US. The only consistent complaint you hear about the LAR-8 is magazines. It's rarely an accuracy or reliability problem. Since the magazines appear to be an issue of the past, the LAR-8 is a viable option.
I have never shot an AR-10 or DPMS. At this point in time, I have no desire to look any further than my LAR-8.
Re: Any user input from RRA LAR-8?
I just bought my first AR-10, and after researching, I decided against the RRA. The main reason being that there is too much that is proprietary on the RRA's. They have a different barrel nut that is not compatible with many of the popular rails, they have a longer pull on the charging handle that will interfere with a PRS stock unless a spacer is added, or you modify it. Also, I have seen a few rifles that have had issues with some mags. RRA has great customer service, and will fix any function issues, but I don't want to be so limited on modding my rifle, and I know I would always have the fear of getting FTF's out of my rifle.
On the other hand, most of the people that have them, absolutely love them.
I say, just keep researching for a little while. You will kick yourself if you buy right now, and learn something tomorrow about your rifle that will make you wish you bought something else.
I just bought my first AR-10, and after researching, I decided against the RRA. The main reason being that there is too much that is proprietary on the RRA's. They have a different barrel nut that is not compatible with many of the popular rails, they have a longer pull on the charging handle that will interfere with a PRS stock unless a spacer is added, or you modify it. Also, I have seen a few rifles that have had issues with some mags. RRA has great customer service, and will fix any function issues, but I don't want to be so limited on modding my rifle, and I know I would always have the fear of getting FTF's out of my rifle.
On the other hand, most of the people that have them, absolutely love them.
I say, just keep researching for a little while. You will kick yourself if you buy right now, and learn something tomorrow about your rifle that will make you wish you bought something else.
Re: Any user input from RRA LAR-8?
[video:youtube]www.youtube.com/watch?v=iLX6wEgSk_g[/video]
I have several RR AR 15s and the LAR 8 and love it. Shoots great.
[video:youtube]www.youtube.com/watch?v=iLX6wEgSk_g[/video]
I have several RR AR 15s and the LAR 8 and love it. Shoots great.
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Patriot Prepper</div><div class="ubbcode-body"> [video:youtube]www.youtube.com/watch?v=iLX6wEgSk_g[/video]
I have several RR AR 15s and the LAR 8 and love it. Shoots great. </div></div>
I saw your video when I was deciding for myself. From what I have seen, it seems like most of the issues with feeding and ejection have to do with out of spec mags. Everything I have seen on accuracy with the rifles have been impressive to say the least.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Patriot Prepper</div><div class="ubbcode-body"> [video:youtube]www.youtube.com/watch?v=iLX6wEgSk_g[/video]
I have several RR AR 15s and the LAR 8 and love it. Shoots great. </div></div>
I saw your video when I was deciding for myself. From what I have seen, it seems like most of the issues with feeding and ejection have to do with out of spec mags. Everything I have seen on accuracy with the rifles have been impressive to say the least.
Re: Any user input from RRA LAR-8?
I ordered an LAR-8 Predator HP despite the proprietary nature of both the upper and lower because it addressed most of the issues I was interested in an AR 7.62 style rifle. It arrived last Thursday. On Sunday, I did 10x shoot 1 clean 1 and shoot 2 clean 1, then tried my first reloads in it using resized, LC 1-fired brass, Amax168, AR-Comp and four different primers. Kind of a shy first date. I shot four 5-shot groups at 100 yards round robin as in OCW testing and here's the result:
I was mildly pleased with the results given they were from a new, Hbar profiled barrel, as opposed to a varmint or bull. Either it likes the CCI 200 / AR-Comp combo, the velocity they produced, or both.
My only regret came from my own misunderstanding of the Shooting Times article that led me to purchase it. I expected the FAL magazine to allow COLs beyond 2.80, but that's about all you can get in there, without removing the shim in the rear of the MAG. For those of you who have the 20 round Polymer mags, does it offer any greater COL capacity without modding?
I haven't shot any other AR type .308s, so I don't know if that kind of performance is common place, right from the get-go or not?
One issue I did not expect is ejector swipes on every single piece of brass, both the LC XM80 break-in rounds and my tame reloads, to exactly the same degree. From what I've been able to read since then, my rig may be over-gassed. For those of you who own and use either an adjustable gas block or adjustable gas tube, is there a preference one way over the other, as opposed to adding weight to the carrier or buffer to change the dwell?
Thanks for any help you can proffer.
John "Hoot" Hill
<span style="font-weight: bold">EDIT:</span> I forgot to say, of the first 50 rounds, not a sing FTF or FTE.
J-
I ordered an LAR-8 Predator HP despite the proprietary nature of both the upper and lower because it addressed most of the issues I was interested in an AR 7.62 style rifle. It arrived last Thursday. On Sunday, I did 10x shoot 1 clean 1 and shoot 2 clean 1, then tried my first reloads in it using resized, LC 1-fired brass, Amax168, AR-Comp and four different primers. Kind of a shy first date. I shot four 5-shot groups at 100 yards round robin as in OCW testing and here's the result:
I was mildly pleased with the results given they were from a new, Hbar profiled barrel, as opposed to a varmint or bull. Either it likes the CCI 200 / AR-Comp combo, the velocity they produced, or both.
My only regret came from my own misunderstanding of the Shooting Times article that led me to purchase it. I expected the FAL magazine to allow COLs beyond 2.80, but that's about all you can get in there, without removing the shim in the rear of the MAG. For those of you who have the 20 round Polymer mags, does it offer any greater COL capacity without modding?
I haven't shot any other AR type .308s, so I don't know if that kind of performance is common place, right from the get-go or not?
One issue I did not expect is ejector swipes on every single piece of brass, both the LC XM80 break-in rounds and my tame reloads, to exactly the same degree. From what I've been able to read since then, my rig may be over-gassed. For those of you who own and use either an adjustable gas block or adjustable gas tube, is there a preference one way over the other, as opposed to adding weight to the carrier or buffer to change the dwell?
Thanks for any help you can proffer.
John "Hoot" Hill
<span style="font-weight: bold">EDIT:</span> I forgot to say, of the first 50 rounds, not a sing FTF or FTE.
J-
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: John_H</div><div class="ubbcode-body">
One issue I did not expect is ejector swipes on every single piece of brass, both the LC XM80 break-in rounds and my tame reloads, to exactly the same degree. From what I've been able to read since then, my rig may be over-gassed. For those of you who own and use either an adjustable gas block or adjustable gas tube, is there a preference one way over the other, as opposed to adding weight to the carrier or buffer to change the dwell?
</div></div>
FWIW: My LAR-8 is also over-gassed. The gun flings brass like King Kong flings airplanes. The recoil is also pretty stout. It's not giving me any problems and gas blocks are expensive so I haven't looked in to it.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: John_H</div><div class="ubbcode-body">
One issue I did not expect is ejector swipes on every single piece of brass, both the LC XM80 break-in rounds and my tame reloads, to exactly the same degree. From what I've been able to read since then, my rig may be over-gassed. For those of you who own and use either an adjustable gas block or adjustable gas tube, is there a preference one way over the other, as opposed to adding weight to the carrier or buffer to change the dwell?
</div></div>
FWIW: My LAR-8 is also over-gassed. The gun flings brass like King Kong flings airplanes. The recoil is also pretty stout. It's not giving me any problems and gas blocks are expensive so I haven't looked in to it.
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KChen986</div><div class="ubbcode-body">
FWIW: My LAR-8 is also over-gassed. The gun flings brass like King Kong flings airplanes. The recoil is also pretty stout. It's not giving me any problems and gas blocks are expensive so I haven't looked in to it. </div></div>
You're right in that it doesn't cause a problem, but it does impede using the swipe check as a means to evaluate whether a load experiment is going up too far. First comes the ejector, then the extractor, then the case head growth and finally it starts to show on the primer, unlike bolt guns, where primers are the main indicator. At least it's that way for me and I dabble a lot in the lunatic fringe AR calibers.
John "Hoot" Hill
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KChen986</div><div class="ubbcode-body">
FWIW: My LAR-8 is also over-gassed. The gun flings brass like King Kong flings airplanes. The recoil is also pretty stout. It's not giving me any problems and gas blocks are expensive so I haven't looked in to it. </div></div>
You're right in that it doesn't cause a problem, but it does impede using the swipe check as a means to evaluate whether a load experiment is going up too far. First comes the ejector, then the extractor, then the case head growth and finally it starts to show on the primer, unlike bolt guns, where primers are the main indicator. At least it's that way for me and I dabble a lot in the lunatic fringe AR calibers.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
i havent fired a dpms or armalite, but i do have a 16" lar-8 and it is a good running gun. several hundred rounds and no problems.
i havent fired a dpms or armalite, but i do have a 16" lar-8 and it is a good running gun. several hundred rounds and no problems.
Re: Any user input from RRA LAR-8?
Being an M14 lover all ill say is the Sadlak Airborne mount has fixed the issue of not"easily" accepting optics. Its a bit pricey but hollds a zero 100%. If you know what you want that's the way to go. Not to deter you from a RRA but nothing compares to a nice shiny Loaded M1a...
Being an M14 lover all ill say is the Sadlak Airborne mount has fixed the issue of not"easily" accepting optics. Its a bit pricey but hollds a zero 100%. If you know what you want that's the way to go. Not to deter you from a RRA but nothing compares to a nice shiny Loaded M1a...
Re: Any user input from RRA LAR-8?
I certainly like my lar 8 . it went through many changes but the configuration its in now suits my needs the best . it is 100% reliable easy to handle and has excellent accuracy .
check out the new polymer mags for 20.00 a piece.
![IMG_20110828_132118.jpg](http://[url="http://i48.photobucket.com/albums/f247/jwb47/IMG_20110828_132118.jpg?t=1314569111"]http://i48.photobucket.com/albums/f247/jwb47/IMG_20110828_132118.jpg?t=1314569111[/url])
![001-1.jpg](http://[url="http://i48.photobucket.com/albums/f247/jwb47/001-1.jpg?t=1317941687"]http://i48.photobucket.com/albums/f247/jwb47/001-1.jpg?t=1317941687[/url])
I certainly like my lar 8 . it went through many changes but the configuration its in now suits my needs the best . it is 100% reliable easy to handle and has excellent accuracy .
check out the new polymer mags for 20.00 a piece.
Re: Any user input from RRA LAR-8?
FALs accept optics just fine with the use of a DSA scope mount. In fact, they even have a special version for the ACOG.
That being said, the LAR-8 is likely going to be far more accurate. With my Varmint rig, I managed a 0.8 MOA 5-shot group with Federal GMM at ~100 yards this weekend, including a called flyer that was absolutely my fault. This was from a bipod on a concrete deck, and without a rear bag. Without a doubt, the rig is capable of 0.5 MOA if I were willing to do my part.
Reliability has been great so far in 250 rounds or so of shooting, even in some less-than-ideal weather. There was a single failure-to-chamber caused by a piece of defective ammo (Prvi Partisan with a bunged-up case mouth); otherwise, the thing runs like a champ and even leaves its brass in a neat little pile about 20 feet away.
FALs accept optics just fine with the use of a DSA scope mount. In fact, they even have a special version for the ACOG.
That being said, the LAR-8 is likely going to be far more accurate. With my Varmint rig, I managed a 0.8 MOA 5-shot group with Federal GMM at ~100 yards this weekend, including a called flyer that was absolutely my fault. This was from a bipod on a concrete deck, and without a rear bag. Without a doubt, the rig is capable of 0.5 MOA if I were willing to do my part.
Reliability has been great so far in 250 rounds or so of shooting, even in some less-than-ideal weather. There was a single failure-to-chamber caused by a piece of defective ammo (Prvi Partisan with a bunged-up case mouth); otherwise, the thing runs like a champ and even leaves its brass in a neat little pile about 20 feet away.
Re: Any user input from RRA LAR-8?
WRT the over-gassing. I ordered the PRI .750 adjustable block from Brownells. I will report in once I have it installed. Never having dealt with their block, I assume you start with it at fully open and close it a partial turn at a time until the swipes (hopefully) stop. Rather than waste my more expensive reloads, I'll adjust it initially using LC XM80, then retest with both a heavy and a light reload. I imagine there is a sweet zone window within which it will work across a range of loads?
John "Hoot" Hill
WRT the over-gassing. I ordered the PRI .750 adjustable block from Brownells. I will report in once I have it installed. Never having dealt with their block, I assume you start with it at fully open and close it a partial turn at a time until the swipes (hopefully) stop. Rather than waste my more expensive reloads, I'll adjust it initially using LC XM80, then retest with both a heavy and a light reload. I imagine there is a sweet zone window within which it will work across a range of loads?
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
With which setups and under what conditions are people experiencing over-gassing? I have the Varmint A4 w/ 20" barrel, and haven't seen any ejector swipes or other signs of too much gas (such as damage to the case mouth or rim) with Federal GMM 168 or Prvi Partisan 168 match.
With which setups and under what conditions are people experiencing over-gassing? I have the Varmint A4 w/ 20" barrel, and haven't seen any ejector swipes or other signs of too much gas (such as damage to the case mouth or rim) with Federal GMM 168 or Prvi Partisan 168 match.
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Eric Bryant</div><div class="ubbcode-body">With which setups and under what conditions are people experiencing over-gassing? I have the Varmint A4 w/ 20" barrel, and haven't seen any ejector swipes or other signs of too much gas (such as damage to the case mouth or rim) with Federal GMM 168 or Prvi Partisan 168 match. </div></div>
In my case, just a stock factory rifle, shooting both XM80 and mild reloads, based upon the velocity. It wasn't hot either day at the range, with temps in the 70s and I was in the shade.
Having removed the gas block in preparation for the new one arriving tomorrow, the port and block hole, though not perfectly centered, were within each others footprint.
There are possible scenarios where the ejector swipes might not be caused by over-gassing, but it seemed like a likely candidate based upon what I've read on other forums. I'll know in a few days.
John "Hoot" Hill
Edit: FWIW, I have shot the same lot of XM80 through a FAL, G3 and M14 with no signs of excess pressure.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Eric Bryant</div><div class="ubbcode-body">With which setups and under what conditions are people experiencing over-gassing? I have the Varmint A4 w/ 20" barrel, and haven't seen any ejector swipes or other signs of too much gas (such as damage to the case mouth or rim) with Federal GMM 168 or Prvi Partisan 168 match. </div></div>
In my case, just a stock factory rifle, shooting both XM80 and mild reloads, based upon the velocity. It wasn't hot either day at the range, with temps in the 70s and I was in the shade.
Having removed the gas block in preparation for the new one arriving tomorrow, the port and block hole, though not perfectly centered, were within each others footprint.
There are possible scenarios where the ejector swipes might not be caused by over-gassing, but it seemed like a likely candidate based upon what I've read on other forums. I'll know in a few days.
John "Hoot" Hill
Edit: FWIW, I have shot the same lot of XM80 through a FAL, G3 and M14 with no signs of excess pressure.
Re: Any user input from RRA LAR-8?
Gosh, Now you all got me worried that it may not be an over-gassing problem. Time will tell and if it's something else, I can still use the block on my 6.5 Grendel. It really beats up the brass, though it doesn't cause head swipes. A lot of the Grendel folks run adjustable blocks. As I said, apart from the swipes, the Predator HP runs great, though admittedly, I don't have any other experience with AR 7.62s to compare it to.
John "Hoot" Hill
Gosh, Now you all got me worried that it may not be an over-gassing problem. Time will tell and if it's something else, I can still use the block on my 6.5 Grendel. It really beats up the brass, though it doesn't cause head swipes. A lot of the Grendel folks run adjustable blocks. As I said, apart from the swipes, the Predator HP runs great, though admittedly, I don't have any other experience with AR 7.62s to compare it to.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: John_H</div><div class="ubbcode-body">In my case, just a stock factory rifle, shooting both XM80 and mild reloads, based upon the velocity.</div></div>
Interesting! I haven't bothered to run any 147gr NATO stuff through my yet; when I finally get around to it, I'll make sure to keep an eye out for the symptom you mentioned.
Adjustable gas does make a ton of sense in a semi-auto that may be exposed to several types of ammunition. I got really spoiled by the FAL system.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: John_H</div><div class="ubbcode-body">In my case, just a stock factory rifle, shooting both XM80 and mild reloads, based upon the velocity.</div></div>
Interesting! I haven't bothered to run any 147gr NATO stuff through my yet; when I finally get around to it, I'll make sure to keep an eye out for the symptom you mentioned.
Adjustable gas does make a ton of sense in a semi-auto that may be exposed to several types of ammunition. I got really spoiled by the FAL system.
Re: Any user input from RRA LAR-8?
I got my adjustable gas block and I must say, I was impressed with the quality of JP. That's the closest toleranced block to barrel fit I've ever seen. Installation was a dream.
We had to finish some work on the rifle range today and it was closed until we finished. It was blowing almost gale force winds and I had brought my setup to shoot once we got done. That took 9 hours and being so beat when we were done, made deciding to skip the session because of the wind an easy call.
I didn't just want to set up the block adjustment, I had also wanted to test some loads using a new bullet for me (Barnes 150 TTSX) and the wind was changing as well as strong, which even at 100 yards, was discouraging conditions for a ladder test. So, I'll have to report back another time.
John "Hoot" Hill
I got my adjustable gas block and I must say, I was impressed with the quality of JP. That's the closest toleranced block to barrel fit I've ever seen. Installation was a dream.
We had to finish some work on the rifle range today and it was closed until we finished. It was blowing almost gale force winds and I had brought my setup to shoot once we got done. That took 9 hours and being so beat when we were done, made deciding to skip the session because of the wind an easy call.
I didn't just want to set up the block adjustment, I had also wanted to test some loads using a new bullet for me (Barnes 150 TTSX) and the wind was changing as well as strong, which even at 100 yards, was discouraging conditions for a ladder test. So, I'll have to report back another time.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pax</div><div class="ubbcode-body">John,
Thanks for all the feedback. I am waiting on a Predator HP right now. Very interested to hear the results from the JP gas block. </div></div>
I've also got one on order- mine is going to get chopped to 2.6" forward of the gas block so I can mount a RSTA promo can.
That should kill the over gassing- lopping 2.5-3.5" off the 20" barrel.
If the gun ever gets to me, I'm going to send it to Adco for the cut/thread/install of the DD lite rail, and while it's out I'm swapping to a AR10 tube with a custom length Slash 6.7 ounce buffer, adding a KAC QD swivel, KAC backup sights and a 4.5-14x50mm Leupold FFP MKIV ERT M3.
I'm pretty excited about the gun, but it's been 4 months on order so far.
The .29MOA group posted above is outstanding! I wonder if CCI just makes a better primer? Beautiful group- I hope mine shoots half as well.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pax</div><div class="ubbcode-body">John,
Thanks for all the feedback. I am waiting on a Predator HP right now. Very interested to hear the results from the JP gas block. </div></div>
I've also got one on order- mine is going to get chopped to 2.6" forward of the gas block so I can mount a RSTA promo can.
That should kill the over gassing- lopping 2.5-3.5" off the 20" barrel.
If the gun ever gets to me, I'm going to send it to Adco for the cut/thread/install of the DD lite rail, and while it's out I'm swapping to a AR10 tube with a custom length Slash 6.7 ounce buffer, adding a KAC QD swivel, KAC backup sights and a 4.5-14x50mm Leupold FFP MKIV ERT M3.
I'm pretty excited about the gun, but it's been 4 months on order so far.
The .29MOA group posted above is outstanding! I wonder if CCI just makes a better primer? Beautiful group- I hope mine shoots half as well.
Re: Any user input from RRA LAR-8?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Griffin Armament</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pax</div><div class="ubbcode-body">John,
Thanks for all the feedback. I am waiting on a Predator HP right now. Very interested to hear the results from the JP gas block. </div></div>
I've also got one on order- mine is going to get chopped to 2.6" forward of the gas block so I can mount a RSTA promo can.
That should kill the over gassing- lopping 2.5-3.5" off the 20" barrel.
If the gun ever gets to me, I'm going to send it to Adco for the cut/thread/install of the DD lite rail, and while it's out I'm swapping to a AR10 tube with a custom length Slash 6.7 ounce buffer, adding a KAC QD swivel, KAC backup sights and a 4.5-14x50mm Leupold FFP MKIV ERT M3.
I'm pretty excited about the gun, but it's been 4 months on order so far.
The .29MOA group posted above is outstanding! I wonder if CCI just makes a better primer? Beautiful group- I hope mine shoots half as well. </div></div>
So, was I just lucky googling the Predtor HP and finding a stocking dealer, or do you save substantially from ordering it directly from RRA?
I doubt it was the superior quality of CCI primers that made it work. No doubt, I just lucked out and found a load that happened to hit the right harmonic. It's more than just the absolute velocity 12 feet from the muzzle. It also involves how quickly the powder turns on and that CCI primer hit it. They are cooler running primers and perhaps AR-Comp likes being turned on slower. I'll find out since the current loads for testing are using the Federal Gold Medal Match primers, which I prefer to use whenever possible. I worked the charge weight and kept the primer the same this time, to find the OCW for that powder, primer and barrel length combination. Once I get through that, I may play with seating depth to see if I can focus it a little finer, but as expensive as these Barnes TTSX bullets run and for a hunting round, you reach a point of diminishing returns for the range my hunting scenario involves. In the north woods of MN, it's rarely beyond 50 yards. Any of the four groups would be fine for "minute of deer" at that distance.
I picked up some blue Permatex Threadloc for the adjusting screw and am doing a test of it as I write this on a stainless steel cap head screw in a piece of aluminum stock that I tapped. IE not in my new block before I know how tight it'll lock to. After it cures fully, I'll have a better idea. If it maintains a degree of adjustability without fear of breaking off the screw or stripping the head, I'll probably run the adjusting screw in to 1/3 closed, let the threadloc set up, and go live with it. I will report in what I find, as well as a range report on the bullet, powder and primer results.
John "Hoot" Hill
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Griffin Armament</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pax</div><div class="ubbcode-body">John,
Thanks for all the feedback. I am waiting on a Predator HP right now. Very interested to hear the results from the JP gas block. </div></div>
I've also got one on order- mine is going to get chopped to 2.6" forward of the gas block so I can mount a RSTA promo can.
That should kill the over gassing- lopping 2.5-3.5" off the 20" barrel.
If the gun ever gets to me, I'm going to send it to Adco for the cut/thread/install of the DD lite rail, and while it's out I'm swapping to a AR10 tube with a custom length Slash 6.7 ounce buffer, adding a KAC QD swivel, KAC backup sights and a 4.5-14x50mm Leupold FFP MKIV ERT M3.
I'm pretty excited about the gun, but it's been 4 months on order so far.
The .29MOA group posted above is outstanding! I wonder if CCI just makes a better primer? Beautiful group- I hope mine shoots half as well. </div></div>
So, was I just lucky googling the Predtor HP and finding a stocking dealer, or do you save substantially from ordering it directly from RRA?
I doubt it was the superior quality of CCI primers that made it work. No doubt, I just lucked out and found a load that happened to hit the right harmonic. It's more than just the absolute velocity 12 feet from the muzzle. It also involves how quickly the powder turns on and that CCI primer hit it. They are cooler running primers and perhaps AR-Comp likes being turned on slower. I'll find out since the current loads for testing are using the Federal Gold Medal Match primers, which I prefer to use whenever possible. I worked the charge weight and kept the primer the same this time, to find the OCW for that powder, primer and barrel length combination. Once I get through that, I may play with seating depth to see if I can focus it a little finer, but as expensive as these Barnes TTSX bullets run and for a hunting round, you reach a point of diminishing returns for the range my hunting scenario involves. In the north woods of MN, it's rarely beyond 50 yards. Any of the four groups would be fine for "minute of deer" at that distance.
I picked up some blue Permatex Threadloc for the adjusting screw and am doing a test of it as I write this on a stainless steel cap head screw in a piece of aluminum stock that I tapped. IE not in my new block before I know how tight it'll lock to. After it cures fully, I'll have a better idea. If it maintains a degree of adjustability without fear of breaking off the screw or stripping the head, I'll probably run the adjusting screw in to 1/3 closed, let the threadloc set up, and go live with it. I will report in what I find, as well as a range report on the bullet, powder and primer results.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
Thanks again John. You don't get a better price ordering direct, I just wanted one with a brake and I am fortunate to know an owner (very standup guy).
Since the barrel nut is proprietary he is making my life easier and threading it prior to the sale.
Thanks again John. You don't get a better price ordering direct, I just wanted one with a brake and I am fortunate to know an owner (very standup guy).
Since the barrel nut is proprietary he is making my life easier and threading it prior to the sale.
Re: Any user input from RRA LAR-8?
That is a nice touch. I wish I knew why RRA elected to not thread the Predator HP Barrel on all of them? I'm guessing they wanted to sell as many as possible, even in states that have issues with threaded muzzles. Speaking of state's with issues, how about sending some Iowa common sense up this way and maybe some day, Minnesotans will be able to own a suppressor. This state is so sport hunter friendly, yet so backwards WRT suppressors and FA. I'd guess I'd rather have it that way than the other way around, but both would be better. If you're heading up this way, drop me a note and we can go to the range down the road from my house and chuck a few. I'm always looking for any good reason to go to the range.
Hoot
That is a nice touch. I wish I knew why RRA elected to not thread the Predator HP Barrel on all of them? I'm guessing they wanted to sell as many as possible, even in states that have issues with threaded muzzles. Speaking of state's with issues, how about sending some Iowa common sense up this way and maybe some day, Minnesotans will be able to own a suppressor. This state is so sport hunter friendly, yet so backwards WRT suppressors and FA. I'd guess I'd rather have it that way than the other way around, but both would be better. If you're heading up this way, drop me a note and we can go to the range down the road from my house and chuck a few. I'm always looking for any good reason to go to the range.
Hoot
Re: Any user input from RRA LAR-8?
<span style="font-weight: bold">OK, so it's not swiping because of being over-gassed.</span>
To frame this endeavor, this was what it did with both XM80 and some tame reloads last time out:
I took the rifle out today despite it being a cool and blustery day to see what the JP adjustable block would do for the problem. For starts, I ran the adjustment set screw all the way in.
I Shot it and obviously it made no attempt to cycle. Hand cycled it and the face was unmarked.
I ran the screw out 2 turns and with my daughter watching from the side, she observed the bolt came a little rearward, barely exposing the case and returned to battery. The face had a slight trace of a crescent moon swipe.
I ran it out 3 more turns and repeated. My daughter said it came back half the way and returned to battery. The swipe was more pronounced, but not as bad as the image above.
I put more than one round in the magazine now. I ran the screw out 1 turn and repeated. It did not go far enough back to eject the case and jammed from the round below it causing the partially extracted case to so off track. The face had a swipe just as bad as the ones in the image.
I ran it out 1 more turn and repeated. It ejected the round but failed to pick up the next one. Scraping the next round about 3/4 of the way back. Face had a swipe like the rounds in the image.
I ran it out 1 more turn and repeated. It ejected the spent round and stripped and chambered the next one. Once again, it had a swipe like in the image.
I repeated with a looser hold on the rifle and it ejected but did a bolt-over on the next round, so there is a tie to how firm you hold the rifle. Same swipe.
I ran the screw out 1 more turn for good measure and ran through 5 rounds with different degrees of firm hold on the rifle. All cycled and all swiped.
I tested my mini-experiment of some Barnes 150gr TTSX, 44.5gr or AR-Comp and 2.735 COL. This is a recipe load from Alliant's web site for the Hornady 150gr GMX and they being somewhat similar to the Barnes TTSX, I used it as a start. It shot near the same POI as the XM80 ammunition, but a much tighter group at .775 MOA at 100 yards. All cycled and all had swipes.
So, it appears that as soon as I start allowing gas into the system, enough to start unlocking and moving the bolt, the swiping begins and gets worse, the more I allow.
This should probably be in a separate <span style="font-style: italic">Advice Sought</span> thread at this point. My gut feeling would be to try adding either some inertial mass to the bolt carrier, or more easily, the buffer, but my gut is also telling me that there might be something else at work here like perhaps the receiver face not being trued. I mention that only because when I first put my scope on this rifle, it shot so far to the left, that I had to crank the windage knob 1 and 1/2 full rotations to the right to get the poi to the center of the target sheet. Now, I move that scope, rings and riser as an entire assembly and rarely have to turn it much to re-zero across three different caliber AR15 uppers. Food for thought.
As for the JP adjustable block. It does what it's supposed to do. I could actually sense the change in the perceived recoil impulse as I adjusted it, but I was also listening/feeling for it. It certainly was not like night and day different, but generally smoother with less than full open gas.
John "Hoot" Hill
<span style="font-weight: bold">OK, so it's not swiping because of being over-gassed.</span>
To frame this endeavor, this was what it did with both XM80 and some tame reloads last time out:
I took the rifle out today despite it being a cool and blustery day to see what the JP adjustable block would do for the problem. For starts, I ran the adjustment set screw all the way in.
I Shot it and obviously it made no attempt to cycle. Hand cycled it and the face was unmarked.
I ran the screw out 2 turns and with my daughter watching from the side, she observed the bolt came a little rearward, barely exposing the case and returned to battery. The face had a slight trace of a crescent moon swipe.
I ran it out 3 more turns and repeated. My daughter said it came back half the way and returned to battery. The swipe was more pronounced, but not as bad as the image above.
I put more than one round in the magazine now. I ran the screw out 1 turn and repeated. It did not go far enough back to eject the case and jammed from the round below it causing the partially extracted case to so off track. The face had a swipe just as bad as the ones in the image.
I ran it out 1 more turn and repeated. It ejected the round but failed to pick up the next one. Scraping the next round about 3/4 of the way back. Face had a swipe like the rounds in the image.
I ran it out 1 more turn and repeated. It ejected the spent round and stripped and chambered the next one. Once again, it had a swipe like in the image.
I repeated with a looser hold on the rifle and it ejected but did a bolt-over on the next round, so there is a tie to how firm you hold the rifle. Same swipe.
I ran the screw out 1 more turn for good measure and ran through 5 rounds with different degrees of firm hold on the rifle. All cycled and all swiped.
I tested my mini-experiment of some Barnes 150gr TTSX, 44.5gr or AR-Comp and 2.735 COL. This is a recipe load from Alliant's web site for the Hornady 150gr GMX and they being somewhat similar to the Barnes TTSX, I used it as a start. It shot near the same POI as the XM80 ammunition, but a much tighter group at .775 MOA at 100 yards. All cycled and all had swipes.
So, it appears that as soon as I start allowing gas into the system, enough to start unlocking and moving the bolt, the swiping begins and gets worse, the more I allow.
This should probably be in a separate <span style="font-style: italic">Advice Sought</span> thread at this point. My gut feeling would be to try adding either some inertial mass to the bolt carrier, or more easily, the buffer, but my gut is also telling me that there might be something else at work here like perhaps the receiver face not being trued. I mention that only because when I first put my scope on this rifle, it shot so far to the left, that I had to crank the windage knob 1 and 1/2 full rotations to the right to get the poi to the center of the target sheet. Now, I move that scope, rings and riser as an entire assembly and rarely have to turn it much to re-zero across three different caliber AR15 uppers. Food for thought.
As for the JP adjustable block. It does what it's supposed to do. I could actually sense the change in the perceived recoil impulse as I adjusted it, but I was also listening/feeling for it. It certainly was not like night and day different, but generally smoother with less than full open gas.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
I forgot to add that my LAR-8 buffer weighs 4.6 ounces. Is that the standard for them as other AR 7.62 variants have a heavier buffer. I assumed this was lighter due to the longer bolt carrier weighing more? I am leaning toward trying more weight in increments until the swiping stops, or I run out of room for adding additional weight, or it won't cycle all the way with the gas adjustment at full open. In my shop, I can cast a continuous lead dowel that will fit inside the buffer, to increase the weight. I have done this in other heavy AR15 calibers like my 450 Bushmaster and .300 OSSM and to a lesser degree my 6.5 Grendel. In all cases, the increased weight reduced perceived recoil somewhat, but more importantly also reduced how badly the brass got beat up. None resulted in any FTE or FTF, nor abnormal carrier wear.In those cases, I was not experiencing ejector swipes. Just beat up rims and bodies.
Thanks for any input on this phenomena.
John "Hoot" Hill
I forgot to add that my LAR-8 buffer weighs 4.6 ounces. Is that the standard for them as other AR 7.62 variants have a heavier buffer. I assumed this was lighter due to the longer bolt carrier weighing more? I am leaning toward trying more weight in increments until the swiping stops, or I run out of room for adding additional weight, or it won't cycle all the way with the gas adjustment at full open. In my shop, I can cast a continuous lead dowel that will fit inside the buffer, to increase the weight. I have done this in other heavy AR15 calibers like my 450 Bushmaster and .300 OSSM and to a lesser degree my 6.5 Grendel. In all cases, the increased weight reduced perceived recoil somewhat, but more importantly also reduced how badly the brass got beat up. None resulted in any FTE or FTF, nor abnormal carrier wear.In those cases, I was not experiencing ejector swipes. Just beat up rims and bodies.
Thanks for any input on this phenomena.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
That mark is probably from the bolt rotating and the case not. The swipe looks to be about the width of rotation of the bolt to unlock at that point on the bolthead. The pressure may still be high enough that the case may still be stuck to the chamber walls against rotation while still thrusting back against the bolt face since the case walls are tapered. When there is no gas to cycle the action and you have to hand cycle, the rearward force is gone and due to no pressure in the case, it does not resist rotation.
The other possibility is that the rotation off the bolt on the case is normal, but that is is an issue with the ejector or ejector/bolt fit. Some of the possibilities are that the ejector face is not true, has burrs on the face or edge, is rough, is tilting slightly as the bolt turns against the casehead, or it is out of spec. Bolt and ejector may be in spec, but tolerance stacking could cause the issue of poor fit. There could be a burr on the bolt face around the hole for the ejector. If that mark is just a burnished area (.ie. no displacement of brass) is may just be cosmetic and may not go away. 7.62x51 has a lot more surface area than 5.56Nato and will stick to the chamber walls more readily.
A simple thing to try is to call RRA and get another ejector. Polish the new one, very slightly break the edges so that there is no sharp edges to act as a cutting edge, and see if that works.
If it is not enough dwell before unlocking, then either a longer path for the gas to reach the carrier, which there isn't a off the shelf fix for, or a heavier buffer/spring combo may delay the rearward carrier movement long enough for the pressure to drop more so that the case also rotates with the bolt head. If you want to possibly confirm this, the extractor may have left marks on the rim as well depending on how much contact and how aggressive that contact is.
-yarro
That mark is probably from the bolt rotating and the case not. The swipe looks to be about the width of rotation of the bolt to unlock at that point on the bolthead. The pressure may still be high enough that the case may still be stuck to the chamber walls against rotation while still thrusting back against the bolt face since the case walls are tapered. When there is no gas to cycle the action and you have to hand cycle, the rearward force is gone and due to no pressure in the case, it does not resist rotation.
The other possibility is that the rotation off the bolt on the case is normal, but that is is an issue with the ejector or ejector/bolt fit. Some of the possibilities are that the ejector face is not true, has burrs on the face or edge, is rough, is tilting slightly as the bolt turns against the casehead, or it is out of spec. Bolt and ejector may be in spec, but tolerance stacking could cause the issue of poor fit. There could be a burr on the bolt face around the hole for the ejector. If that mark is just a burnished area (.ie. no displacement of brass) is may just be cosmetic and may not go away. 7.62x51 has a lot more surface area than 5.56Nato and will stick to the chamber walls more readily.
A simple thing to try is to call RRA and get another ejector. Polish the new one, very slightly break the edges so that there is no sharp edges to act as a cutting edge, and see if that works.
If it is not enough dwell before unlocking, then either a longer path for the gas to reach the carrier, which there isn't a off the shelf fix for, or a heavier buffer/spring combo may delay the rearward carrier movement long enough for the pressure to drop more so that the case also rotates with the bolt head. If you want to possibly confirm this, the extractor may have left marks on the rim as well depending on how much contact and how aggressive that contact is.
-yarro
Re: Any user input from RRA LAR-8?
Thanks Yarro for the suggestions and opinions. Looking at the heads of the first two cases shot. Those being with the gas port closed and very slightly open, where there is no swiping, show no imprinting from either the ejector or the extractor, so the case is not backing out prior to the bolt starting to unlock. The ejector itself has the edges slightly radiused and is smoothed. No way it could be the swiper as the size of the swipe is the diameter of the ejector hole as, not the ejector itself. That hole does not have any burrs on the edge, but the edge is quite sharp, consistent with the precise sharpness of the swipe mark. FWIW, those marks are not much deeper than the face and no discernible brass <span style="font-style: italic">plows up</span>on the leading edge. They're just fresh brass as opposed to the more tarnished brass of the head, so they really stand out. I have cast and dimensioned a series of lead slugs the same dimension as the sintered iron ones in the buffer and when I put them in, instead of the iron ones, they bring the weight of the buffer from 4.6 ounces to 6.0 ounces or 30% more. I do not want to change more than one variable at a time, so I will see what the additional buffer weight will accomplish, before I radius the edge of the ejector hole so it's not so sharp. Starting with the full 6 ounces and the original gas port block back in place, if that eliminates the swipes, without effecting stripping, chambering or ejecting, I will be taking my smithing tools with me and will disassemble the buffer at the range work bench and remove one of the 5 lead slugs, replacing it with the original sintered iron one and repeat one by one until swiping starts again. I will also try to keep an eye on perceived recoil impulse at the same time more out of interest than concern. I use a <span style="color: blue"><span style="font-weight: bold">DIY Carrier Weight</span></span> in two of my high power AR15 uppers and it reduces all kinds of injustice being visited upon their brass, as well as taming perceived recoil as well, with no apparent resulting issues like unusual wear patterns or battering the cam pin or lugs. So if the fully weighted buffer eliminates the issue, I may add a semi-permanent weight of the same design to the bolt carrier and return the buffer to its original weight. I'm more comfortable with the physics of the bolt carrier being heavier than the buffer. No sense peening the aluminum buffer face due to it being heavier and slamming up against a steel bolt carrier during return to battery. Better to just have a heavier colt carrier.
I get off early tomorrow and will stop at the range on the way home to do some testing. Saturday's out as I'm tweaking a friends Remington 700 and need to so some testing of it and the ammunition I loaded for it on Saturday. I'm taking some friends to the range Sunday to sight in their deer rifles, so it's already spoke for. Both weekend days also include additional honey-do's to prep the house and yard for the arrival of winter in a few weeks. It comes early up here.
As long as I'm not veering this thread off course, I will continue to report in on my progress as it is after all an LAR-8 and may help other potential buyers avoid having to go through this discovery process themselves.
John "Hoot" Hill
Thanks Yarro for the suggestions and opinions. Looking at the heads of the first two cases shot. Those being with the gas port closed and very slightly open, where there is no swiping, show no imprinting from either the ejector or the extractor, so the case is not backing out prior to the bolt starting to unlock. The ejector itself has the edges slightly radiused and is smoothed. No way it could be the swiper as the size of the swipe is the diameter of the ejector hole as, not the ejector itself. That hole does not have any burrs on the edge, but the edge is quite sharp, consistent with the precise sharpness of the swipe mark. FWIW, those marks are not much deeper than the face and no discernible brass <span style="font-style: italic">plows up</span>on the leading edge. They're just fresh brass as opposed to the more tarnished brass of the head, so they really stand out. I have cast and dimensioned a series of lead slugs the same dimension as the sintered iron ones in the buffer and when I put them in, instead of the iron ones, they bring the weight of the buffer from 4.6 ounces to 6.0 ounces or 30% more. I do not want to change more than one variable at a time, so I will see what the additional buffer weight will accomplish, before I radius the edge of the ejector hole so it's not so sharp. Starting with the full 6 ounces and the original gas port block back in place, if that eliminates the swipes, without effecting stripping, chambering or ejecting, I will be taking my smithing tools with me and will disassemble the buffer at the range work bench and remove one of the 5 lead slugs, replacing it with the original sintered iron one and repeat one by one until swiping starts again. I will also try to keep an eye on perceived recoil impulse at the same time more out of interest than concern. I use a <span style="color: blue"><span style="font-weight: bold">DIY Carrier Weight</span></span> in two of my high power AR15 uppers and it reduces all kinds of injustice being visited upon their brass, as well as taming perceived recoil as well, with no apparent resulting issues like unusual wear patterns or battering the cam pin or lugs. So if the fully weighted buffer eliminates the issue, I may add a semi-permanent weight of the same design to the bolt carrier and return the buffer to its original weight. I'm more comfortable with the physics of the bolt carrier being heavier than the buffer. No sense peening the aluminum buffer face due to it being heavier and slamming up against a steel bolt carrier during return to battery. Better to just have a heavier colt carrier.
I get off early tomorrow and will stop at the range on the way home to do some testing. Saturday's out as I'm tweaking a friends Remington 700 and need to so some testing of it and the ammunition I loaded for it on Saturday. I'm taking some friends to the range Sunday to sight in their deer rifles, so it's already spoke for. Both weekend days also include additional honey-do's to prep the house and yard for the arrival of winter in a few weeks. It comes early up here.
As long as I'm not veering this thread off course, I will continue to report in on my progress as it is after all an LAR-8 and may help other potential buyers avoid having to go through this discovery process themselves.
John "Hoot" Hill
Re: Any user input from RRA LAR-8?
OK, "<span style="font-style: italic">yes we have no bananas</span>".
I took a co-worker and his son as guests to the range, which was busy with others getting ready for deer season opener in two weeks. While they were busy, I played with the Predator HP.
From the last effort, using an adjustable gas block, as soon as I allowed enough gas to hit the key hard enough to start it back and spin the bolt, I got the swiping. This was long before it was even close to cycling the action, so. it appears that it's not over-gassed.
I increased the buffer weight 30% and as soon as the gas overcame the increased mass enough to start the bolt turning, I got the swiping. A note that it starts somewhat slighter as I increase the gas flow, before looking the same as when the buffer was stock weight.
Those were candidates #1 & #2 for solutions to this, so now it becomes a more esoteric issue of live with it or get creative. I will be checking the chamber neck length as well as radiusing the edge of the ejector hole ever so slightly and retesting. The rifle shoots excellent and does not beat up the brass in any other way. The chamber walls don't seem unduly rough so as to hang on to the case longer than it should. It's an interesting challenge that ends in either a Win or a Win since I have no other issues with the rifle. Some would think of it as a bother, but I look at it as a learning opportunity and entertaining as I really do enjoy doing this kind of work. I troubleshoot for a living and do a good job, mainly because I enjoy troubleshooting and fixing.
I will report back on the impact of lessening the sharpness of the ejector hole, though it is not burred. The net effect of the heavier buffer seems to be a smoother shooting rifle, so I may just stay with that if it does not cause any issues. I am going back to the stock gas block though.
Coffee's done! Shop time!
Hoot
OK, "<span style="font-style: italic">yes we have no bananas</span>".
I took a co-worker and his son as guests to the range, which was busy with others getting ready for deer season opener in two weeks. While they were busy, I played with the Predator HP.
From the last effort, using an adjustable gas block, as soon as I allowed enough gas to hit the key hard enough to start it back and spin the bolt, I got the swiping. This was long before it was even close to cycling the action, so. it appears that it's not over-gassed.
I increased the buffer weight 30% and as soon as the gas overcame the increased mass enough to start the bolt turning, I got the swiping. A note that it starts somewhat slighter as I increase the gas flow, before looking the same as when the buffer was stock weight.
Those were candidates #1 & #2 for solutions to this, so now it becomes a more esoteric issue of live with it or get creative. I will be checking the chamber neck length as well as radiusing the edge of the ejector hole ever so slightly and retesting. The rifle shoots excellent and does not beat up the brass in any other way. The chamber walls don't seem unduly rough so as to hang on to the case longer than it should. It's an interesting challenge that ends in either a Win or a Win since I have no other issues with the rifle. Some would think of it as a bother, but I look at it as a learning opportunity and entertaining as I really do enjoy doing this kind of work. I troubleshoot for a living and do a good job, mainly because I enjoy troubleshooting and fixing.
I will report back on the impact of lessening the sharpness of the ejector hole, though it is not burred. The net effect of the heavier buffer seems to be a smoother shooting rifle, so I may just stay with that if it does not cause any issues. I am going back to the stock gas block though.
Coffee's done! Shop time!
Hoot
Re: Any user input from RRA LAR-8?
This will be the last update about the head swiping. In troubleshooting, one of the bigger trappings is looking for complex solutions to simple problems. After putting a slight polish on the bolt face, the swiping disappeared. I removed the adjustable gas block and reinstalled the original. I left the additional 1.4 ounces of buffer weight in, as it does not impact cycling reliability. while softening the event somewhat. I will run with that for a while, watching for any adverse effect.
Thanks to everyone for your perseverance and suggestions.
We now return the thread to it's original path.
Hoot
EDIT: Someone asked and I forgot to mention, the chamber is 2.03 inches long.
H-
This will be the last update about the head swiping. In troubleshooting, one of the bigger trappings is looking for complex solutions to simple problems. After putting a slight polish on the bolt face, the swiping disappeared. I removed the adjustable gas block and reinstalled the original. I left the additional 1.4 ounces of buffer weight in, as it does not impact cycling reliability. while softening the event somewhat. I will run with that for a while, watching for any adverse effect.
Thanks to everyone for your perseverance and suggestions.
We now return the thread to it's original path.
Hoot
EDIT: Someone asked and I forgot to mention, the chamber is 2.03 inches long.
H-
