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Ended up snagging a NIB LM8 12.5” with grip stop, pic rail, and panels for $700. Also found a carrier for $200 though i think the carrier might bite me in the ass. Dunno if i can reassemble it for under retail. Thoughts?
I have removed my barrel without having to remove my bipod attachment. I think the issue may be if you have rails installed on the sides. Also to add after getting down to the end of this thread, I havent had to trim anything off my mlok nuts. Might depend on rail manufacturer
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Virtually all bolts today will work with the MWS.
Aero, toolcraft, kak, JP, lantec. At one point d. Wilson sold some uppers with kak bolts.
I saw that but thought it would have to be headspaced. I’m thinking now of doing a jp barrel and bolt. Having Wilson convert it and having an adjustable gas block
Having a bolt "headspaced" is not a thing.
The headspace is set when the barrel is chambered, the only thing you can do is confirm that the headspace is within the min/max SAMMI specification with a given bolt using go and no-go headspace gauges. There's no adjustment. It's either good or bad.
As far as I know armalite is still the odd one out. They’ll work in the mws carrier but have to match the barrel. I want to say the bolt face is ~.004-5” deeper.
Oh i see. So theoretically should be able to use whatever bolt and barrel as long as it’s the same pattern?
Kinda leaning back towards 18" over 16" Seems LMT doesn't offer a LW SS 18" so I'm curious how much do y'alls 18" rigs weigh? How is the accuracy of LMT's SS barrel?
I'm considering just grabbing a Lilja AR10 18" and having Dwilson convert it with an SLR at this point.
I'm considering just grabbing a Lilja AR10 18" and having Dwilson convert it with an SLR at this point.
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AR 10 Assembled Upper Receivers come with the forward assist and dust cover pre installed while allowing you to choose your barrel and handguard.
www.primaryarms.com
It’ll be interesting to see if this in fact the old 15.5” design or the new 15.3”.
So I got a new to me 13.5 308, running it suppressed with Sandman S Mil. When I got it the seller said it had about 300 rounds. I cleaned it and lubed it when I first got it. Ran a box of IMI 175 to zero and see drop at 275 (my max range at home) with no issues. Since then I’ve put about 50 more rounds thru it, mix of IMI and two 178 eldx/Varget loads. I am getting vertical stringing with the reloads terrible, like 4-5 inches, almost zero horizontal deviation. I am getting it with the IMI too, but not as bad. Also getting FTE, about 1 in 5 rounds. Has happened with both the IMI and reloads. The FTEs aren’t the classic stove pipe, usually the brass is spun around in the chamber.
Is it possible the barrel screws aren’t torqued correctly? Or is the FTE an overgas issue? Every reload was individually measured on an M500, so I shouldn’t be having that terrible stringing (plus it also shows up with IMI but not as bad). Scope/mount shouldn’t be an issue as it’s an NX8 and I just torqued everything to spec there. I know I need to do a proper OCW test, but I just tried to loads a grain apart to see if I was in the ballpark. I wasn’t expecting groups that bad.
Is it possible the barrel screws aren’t torqued correctly? Or is the FTE an overgas issue? Every reload was individually measured on an M500, so I shouldn’t be having that terrible stringing (plus it also shows up with IMI but not as bad). Scope/mount shouldn’t be an issue as it’s an NX8 and I just torqued everything to spec there. I know I need to do a proper OCW test, but I just tried to loads a grain apart to see if I was in the ballpark. I wasn’t expecting groups that bad.
To establish a baseline: How does the rifle run with the silencer off?
What’s your ejection pattern look like unsuppressed and then suppressed? Cases ejecting towards the 1-1:30 or closer to 2:30-3:00?
LMT MWS rifles are notoriously over gassed (which aides in battlefield reliability), but makes using suppressors (even low backpressure cans) problematic.
From some of the symptoms your describing I’d definitely try a BRT 50/50 gas tube to see if that corrects the FTE issues unless you want to send to Dave Wilson for an adjustable gas block modification. You might also need to experiment with a slash extra heavy buffer (8 oz) and spring to slow down the BCG and smooth the gas out.
What do your 100 yard groups look like? Do they trend upwards with heat? Or randomly up and down?
Vertical stringing is typically improper breathing (mainly if prone), inconsistent loading of the bipod, or shoulder pressure into the rifle if using a rear bag, giving up on the shot...basically relaxing the rear bag hand at the same time the trigger is pressed.
Definitely clean, pull, and properly retorq the barrel to spec (140 in/lbs)
What’s your ejection pattern look like unsuppressed and then suppressed? Cases ejecting towards the 1-1:30 or closer to 2:30-3:00?
LMT MWS rifles are notoriously over gassed (which aides in battlefield reliability), but makes using suppressors (even low backpressure cans) problematic.
From some of the symptoms your describing I’d definitely try a BRT 50/50 gas tube to see if that corrects the FTE issues unless you want to send to Dave Wilson for an adjustable gas block modification. You might also need to experiment with a slash extra heavy buffer (8 oz) and spring to slow down the BCG and smooth the gas out.
What do your 100 yard groups look like? Do they trend upwards with heat? Or randomly up and down?
Vertical stringing is typically improper breathing (mainly if prone), inconsistent loading of the bipod, or shoulder pressure into the rifle if using a rear bag, giving up on the shot...basically relaxing the rear bag hand at the same time the trigger is pressed.
Definitely clean, pull, and properly retorq the barrel to spec (140 in/lbs)
Never shot it unsuppressed, so I guess that would be a thing to do regardless. Ejection is forward, and the brass always has a “D” shape dent in the case mouth opening. Muzzle device is P&W, so BRT would be the way to address the gas.
I definitely won’t say my shooting isn’t above criticism haha. I am shooting off a bipod. Would shooting off a bag be better at removing that variable? I’ve never really had an issue with vertical stringing this bad, but it is a new gun to me so I wouldn’t rule anything out.
First thing I’ll do is pull and retorque the barrel, then fire two groups with each ammo. I read the FTE can also be attributed to loose barrel, but def seems gas related. The only puzzle is why it was fine for awhile, then showed up. I’ll see if that fixes anything before moving forward addressing the overgas possibility.
Forward ejection, case ejector marks, and case dent’s can definitely be symptoms of an over gassed system. Even if the barrel is P&W if you want to go adjustable gas block I’m confident Dave Wilson can do it.
Recommend removal of the barrel, clean barrel end, clean down in hole, re-oil end of barrel and hole, stand gun on end and insert barrel. Then with gun standing on end gently tighten the screws evenly. Torque to correct 140 inch/lbs. It should shoot good again. Crap ammo should be in the 1" area and handloads/match sub 3/4".
The first time I took my barrel off to clean the breach area I re-installed it with the gun laying down on the bipod. The barrel didnt like the way it went back on and I was shooting 4” groups at 100. I took the barrel off and cleaned it then re-installed. The gun went right back to shooting 1/2-3/4 inch groups.
Try and eliminate as many variables as you can so if you feel pulling your bipod and bagging it might help do it. With an large frame gas gun you have to be perfectly consistent every shot - i.e get behind the rifle exactly the same way, rifle in your shoulder pocket and on the rear bag exactly the same, same cheek pressure on stock, same slow pressure on the trigger with follow through, etc. My bolt action guns are more forgiving. Maybe it has to do with the chassis/stock. However, it's likely the fact that there's no reciprocating mass in a bolt gun and only one recoil impulse vs three in a gas gun. IDK.
But much as I'd like to believe otherwise, I do think it's the shooter not the gun. Personally, my groups open up with a "flyer" it's usually the result of vertical stringing, which I attribute to poor recoil management.
“From Frank Galli“
Using a semi automatic large frame rifle as a precision rifle takes a bit more understanding as the rifle will exploit any weaknesses in your fundamentals of marksmanship.
Most guys out there shooting an M4 type rifle are doing so in a dynamic fashion. Usually from a standing or alternate position, moving very dynamic on large close targets. So when these same people move to an AR10 Type rifle in a larger caliber they run into problems with accuracy. We want to look at some fundamental differences in the platform, and how you shoot them accurately.
The AR10 type rifle is heavier, slower, and pushing a bigger bullet with more powder behind it. Depending where the gas key is in relationship to the end of the barrel can matter, as well as how it reacts to the last round in the magazine. These issues are definitely debatable, however the end results speak for themselves. Generally speaking those who ignore the weight difference and the movement in the system fail to use them as a true precision rifle.
For the shooter, the weight and movement in the system is going to exploit any weakness in your fundamentals of marksmanship, especially Trigger Control and Follow Through. If you have a habit of "tapping" your trigger on your bolt gun the gas gun will exploit this dramatically. A great example of this problem is when a shooter experiences the "double tap" with a 308 Gas Gun. They immediately want to blame the trigger or the system but its all shooter. You must follow through completely and allow the recoil pulse to be over before moving on. You don't want to reset the trigger on recoil like with a handgun or carbine in a dynamic situation. You want to delay that reset so we have a distinct and audible click. Trigger reset is key and shows the shooter he is doing it correctly.
Ammunition will matter as well in these systems. Generally speaking they don't like ammunition going over 2650fps for a 175gr 308. The other popular calibers, 6.5mm and 6mm don't have as big an issue because the bullet is moving faster, but in a 308, try to stick with match ammo below 2650. If you are not using Match ammunition, the same you would use in your bolt gun you can't expect bolt gun like results. So be conscious of what you feed your AR10 Type rifle.
It's not your M4 and needs to be treated a bit different. Like the difference between driving an 18 Wheeler Tractor Trailer or a Porsche 911... you drive both the same yet completely different.
USGILT - Thanks for that detailed response, great info! I pulled the barrel tonight, and it was well oiled but I did see some very fine metal shavings. Couldn't see anything obvious where they came from, so I am guessing that they were there when the barrel was installed last time, just shop debris or something. Cleaned up, reoiled, reassembled and torqued with the rifle in the vertical position. Next I'll test fire some groups, probably this weekend, and report back. I'll do that before changing anything gas related to see if that changed any of the issues.
Also, thank you for those "tips". I'll re-read that a few more times and try and work on that. I do remember, that my tightest group when I first got the gun was when I had a very heavy load on the bipod. It was 3 shots all touching, but also about 1.5" lower than a light to no load bipod. Of course, having a heavy bipod load isn't repeatable in any other shooting position.
Also, thank you for those "tips". I'll re-read that a few more times and try and work on that. I do remember, that my tightest group when I first got the gun was when I had a very heavy load on the bipod. It was 3 shots all touching, but also about 1.5" lower than a light to no load bipod. Of course, having a heavy bipod load isn't repeatable in any other shooting position.
Below are instructions LMT sent me via email for barrel replacement. A big takeaway for me is to close the bolt forward before tightening and torquing.
Did not do that, I had the bolt removed...thanks for the heads up.
Just picked up a 15.3" MRP-H upper and I'm starting to explore barrel options - 100% suppressed use. I want a 16" 308 to start with.
For those who went the D. Wilson conversion route - Do you use the LMT bolt and carrier or can you use a DMPS pattern BCG with the upper and his barrels?
Has anyone cut a 20" barrel to 16"? Curious is the longer gas system would benefit suppressor use.
Thanks.
For those who went the D. Wilson conversion route - Do you use the LMT bolt and carrier or can you use a DMPS pattern BCG with the upper and his barrels?
Has anyone cut a 20" barrel to 16"? Curious is the longer gas system would benefit suppressor use.
Thanks.
Got out yesterday and shot a few groups with the 13.5. Fired 16 rounds, and had no FTE after removing and installing the barrel per above instructions. Small sample size, but based on past I was getting 1 in 5 FTE. I did not clean or oil BCG at all.
Groups didn’t really change. Was 1-2 MOA with IMI 175 (first 3 pictures) and the last picture is 178 eldx reloads (vertical string). Based on the difference in the groups, seems my vertical stringing is ammo based. Each charge was weighed on m500 scale, and was using new Norma brass with Varget. Need to do a proper OCW test.
Groups didn’t really change. Was 1-2 MOA with IMI 175 (first 3 pictures) and the last picture is 178 eldx reloads (vertical string). Based on the difference in the groups, seems my vertical stringing is ammo based. Each charge was weighed on m500 scale, and was using new Norma brass with Varget. Need to do a proper OCW test.
Attachments
Good to hear your FTE problems are gone.
3rd groups can be difficult to judge accuracy. Recommend shooting a couple 5rd control groups with FGMM 168gr and if you can your 175gr IMI before moving on to your reloads so you know what “your” rifle system is capable of.
What’s the average chronograph velocity’s on your groups by bullet weight?
Your 5rd reloaded group could be velocity related however, if shot 1-5 are descending in sequence that could be breathing and/ relaxing your rear bag = breaking the shot on the exhale or not keeping a consistent 2/3 squeeze on the rear bag = your groups settling lower and lower between shot 1-5.
Also recommend using a consistent refined aiming point based on the optic/reticle you have.
3rd groups can be difficult to judge accuracy. Recommend shooting a couple 5rd control groups with FGMM 168gr and if you can your 175gr IMI before moving on to your reloads so you know what “your” rifle system is capable of.
What’s the average chronograph velocity’s on your groups by bullet weight?
Your 5rd reloaded group could be velocity related however, if shot 1-5 are descending in sequence that could be breathing and/ relaxing your rear bag = breaking the shot on the exhale or not keeping a consistent 2/3 squeeze on the rear bag = your groups settling lower and lower between shot 1-5.
Also recommend using a consistent refined aiming point based on the optic/reticle you have.
I'll pick up a box of 168 and maybe 185 just to try. I think local Cabelas has them in stock. I don't have a chronograph so....
The 5 rd reload group wasn't shot in descending order as labelled. Sorry for not being more accurate on that labeling. I don't remember the order other than I think the top 1 was first, and maybe the bottom was 3rd. So basically no consistent pattern.
Scope is an NX8 2.5-20. I'll try using a dot target next time.
It is a chrome lined barrel
Consistent bipod loading, recoil management, and cheekweld may eliminate some of the inconsistency.I'll pick up a box of 168 and maybe 185 just to try. I think local Cabelas has them in stock. I don't have a chronograph so....
The 5 rd reload group wasn't shot in descending order as labelled. Sorry for not being more accurate on that labeling. I don't remember the order other than I think the top 1 was first, and maybe the bottom was 3rd. So basically no consistent pattern.
Scope is an NX8 2.5-20. I'll try using a dot target next time.
It is a chrome lined barrel
That isn’t a shot at you or your skill level as I don’t know how long you’ve been shooting a large frame. Just a suggestion if you’re new to them. If you’re an experienced shooter, disregard.
Won't disregard at all, I am new to large frames. Appreciate the tips from you all and will incorporate them over the next few months.
Additionally, I have found more consistency FOR ME, when pulling back hard into my shoulder and not loading the bipod too much. I say this to say, experiment with a few suggestions to find what works best for you.
I agree, this has made my large frame AR shooting much more consistent.
What is the ID of the gas block on LMT barrels? .750 or .875? About to order a seekin's select adjustable.
Hi everyone I purchased my first MWS a few months ago from a fellow member it’s a Sharpshooter 2 and I’m thinking I may have found the best do it all platform. I’m starting to venture out and begin to swap around barrels and absolutely love the interchangeability. I spun up some loads for the factory barrel which is a 308 20” SS 1:11.25 twist. I was able to settle on a moderate, reliable load that grouped quite well. That same load did not run well at all in the 13.5 CL barrel. The bcg didn’t have enough power to reliable grab the next round let alone lock back after the last round. The load I’m using is published on the hogdon site as a 178gr eldx over 39gr of IMR 3031. Seated without crimp to a depth to just clear the magazine. It seemed like this is a pretty average load but not enough to cycle in the 13.5? I’m just a bit puzzled and thinking I’ll just work up a hotter load as I have another 2 grains or so before I hit max. Are there any further recommendations before I hit the loading bench?
Thanks in advance!
Thanks in advance!
Does anyone know who makes LMT's barrels? I know KAC makes their own barrels(except for the LPR).. does LMT make their own barrels also or do they outsource from someone..??
As far as I remember reading, they make their own barrels from Rock Creek blanks
Thank you sir!
What kinda groups would yall expect with match ammo from the 16" chrome lined?
In my experience, in a 5 round group I’d usually have 3 to 4 in a minute or better and the rest pushing it to around 1.5. Some people say they get better than that but I wouldn’t count on it.
I'm getting about .75 MOA from my 20" SS .308 at 200 yds with 168 SMK . I'm not a seasoned shooter, and granted I'm also shooting box ammo, so much better could be had. I'm sure 1 MOA can be done in a 16" CL with practice, good form and ammo.
BTW - for yall Canuck monolithic fans.. are these available to civvies up north?
www.thefirearmblog.com
FIRST LOOK: Colt Canada's C20 Sniper Rifle
A couple of weeks ago at DSEI 2019, in London, I had the chance to take a look at Colt Canada's latest offering, a 7.62x51mm semi-automatic precision rifle developed for the Canadian Army - the C20 Semi-Automatic Sniper Weapon.
www.thefirearmblog.com
I’m pretty sure LMT is making their own barrels both cut rifled and button rifled chrome lined. They haven’t used Rock Creek in years.
My best group with a 16' LW chrome lined barrel is around 1moa with American Marksmen 175 SMK from a bipod, rear bag, and LMT 2-stage trigger. I believe with better ammo and shooter it will go under an inch.
To be honest, what I like most about this barrel is the consistency with different ammo, pretty much everything I have shot so far is under 2moa.
This is from my last range trip - Portuguese delinked M80 (FNM) surplus from 1980 was approx 1.7moa, IGMAN "sniper" 168 around 1.3moa, IWI M80 ~1.6moa. That was again with the same setup - bipod, bag, and a bad shooter with a moderate hangover on that particular day.
Wouldnt be surprised...
However Ive also heard KAC is the one who makes LMT's cut rifled tubes, and also supplies LMT with other various parts as well.
@Frank Green any idea?
Okay, well I was pretty sure LMT was cutting their own, but anyone know where else they would be sourcing their blanks from?
