BCG not cycling in my LAR8

[Swift]

Took it out for the first time today and I was surprised at how it performed, and not in a good way. After each shot, the bolt wouldn't cycle. It just stayed put. I had to manually cycle the charging handle after every shot, basically turning my rifle into a funky lookin bolt gun.

This rifle is new to me and this is my first 308 of the type so I'm a little lost. Initial thoughts are something with the gas system because they eject just fine when you cycle the charging handle.

I didn't get any stuck cases and the bolt and CH move freely when operated manually so chamber pressure and expansion doesn't seem to be the issue.

Any thoughts before I start tearing into this thing?

 

[Powder_Burns]

Re: BCG not cycling in my LAR8

Hand cycle the bolt half a thousand times. Don't forget the lube, you gotta break these gas guns in. MFG's seldom actually test fire the uppers.

Also, whats up with your gas system? Drilled and pinned FSB, set screw gas block? See if air is flowing through your system. You can blow compressed air in the barrel and plug one end, listen or feel for air flow through your gas tube. If the air isn't flowing, its probably indicative of a problem.

 

[Swift]

Re: BCG not cycling in my LAR8

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Powder Burns</div><div class="ubbcode-body">Hand cycle the bolt half a thousand times. Don't forget the lube, you gotta break these gas guns in. MFG's seldom actually test fire the uppers.

Also, whats up with your gas system? Drilled and pinned FSB, set screw gas block? See if air is flowing through your system. You can blow compressed air in the barrel and plug one end, listen or feel for air flow through your gas tube. If the air isn't flowing, its probably indicative of a problem. </div></div>

It's a set screw gas block. I'll have to track down some Duster to do some testing. Where should I check for leaks? I would assume the gas block and where the tube meets the BCG in the receiver. Never heard of a gas tube failing anywhere else.

I have contacted the previous owner to see if they had the same problems. He's a fellow Hider so hopefully he can give me some insight as well as a ballpark round count.

 

[MidwestPX]

Re: BCG not cycling in my LAR8

I wonder if the hole in the gas block isn't properly seated over the hole in the barrel.

 

[ORD]

Re: BCG not cycling in my LAR8

First things first...since it is just a set screw gas block, it should be relatively easy to remove, inspect and reinstall.

Pull the upper off the lower, then drop the BCG/CH out of the upper. While you have the carrier in your hand, check to see that your key is tight on the carrier. If the screws are lose/not staked, torque them down to 55 in/lbs, then reasseble your upper/lower and test fire. If that doesn't do it...proceed as follows.

Next, loosen the gas block set screws so that you can slide the gas block/tube forward on the barrel. First determine if there is actually a hole in the barrel for the gas to vent into the gas block (yes...I know...but I have seen barrels from MAJOR companies make it through QC and get shipped, supposedly with a successful test fire, that didn't have a gas port drilled)!

If there is in fact a gas port drilled into the barrel, it is possible that the alignment of the gas block was so bad (or it was too lose) that you weren't getting any gas back to cycle the action. If that's the case, you can adjust the positioning of the gas block and then tighten down the set screws so that you get proper gas flow.

Also, check for impingements of the gas tube (is is bent, dented, etc.).

 

[Swift]

Re: BCG not cycling in my LAR8

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body">First things first...since it is just a set screw gas block, it should be relatively easy to remove, inspect and reinstall.

Pull the upper off the lower, then drop the BCG/CH out of the upper. While you have the carrier in your hand, check to see that your key is tight on the carrier. If the screws are lose/not staked, torque them down to 55 in/lbs, then reasseble your upper/lower and test fire. If that doesn't do it...proceed as follows.

Next, loosen the gas block set screws so that you can slide the gas block/tube forward on the barrel. First determine if there is actually a hole in the barrel for the gas to vent into the gas block (yes...I know...but I have seen barrels from MAJOR companies make it through QC and get shipped, supposedly with a successful test fire, that didn't have a gas port drilled)!

If there is in fact a gas port drilled into the barrel, it is possible that the alignment of the gas block was so bad (or it was too lose) that you weren't getting any gas back to cycle the action. If that's the case, you can adjust the positioning of the gas block and then tighten down the set screws so that you get proper gas flow.

Also, check for impingements of the gas tube (is is bent, dented, etc.). </div></div>

Noted. I'm gonna give it a good cleaning first then follow those steps. I'll post a follow up.

 

[glocksig40]

Re: BCG not cycling in my LAR8

Is it by chance an adjustable gas block that is closed off? I swapped my non-adjustable to adjustable and run suppressor. When I took them to the range the first time, I forgot to open the gas block up and it did just the same as yours did. I opened the adjustment screw and it worked fine.

 

[Swift]

Re: BCG not cycling in my LAR8

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: stacyp</div><div class="ubbcode-body">Is it by chance an adjustable gas block that is closed off? I swapped my non-adjustable to adjustable and run suppressor. When I took them to the range the first time, I forgot to open the gas block up and it did just the same as yours did. I opened the adjustment screw and it worked fine. </div></div>

It's a fixed block so that's out of the equation. I just disassembled and cleaned everything pretty thoroughly. Inspected the gas tube and didn't find any dents/chips/cracks/bends/etc. Just a little fouling on the ends. Everything else seemed to be in pretty good order, although the gas port on the barrel seemed a little small, esp considering the larger caliber. I used a thin hex wrench and cleaned it out.

I apologize for not taking a before photo but this was afterwards. The opening was about 1/3 this size when I started.


If the port was choked off, it might not have been letting enough gas through to cycle the bolt. Not sure if this is the fix but all else seems ok. Next step would be a smith.

 

[exhogflyer]

Re: BCG not cycling in my LAR8

Look at the inside of the gas block, you should see a "carbon ring" at or near the port to the gas tube.Make sure it's centered OVER the port itself.Can you blow into the gas tube and feel it coming out the port?Another thing to check are the gas rings on the bolt......make sure they are there and not broken.

 

[dareposte]

Re: BCG not cycling in my LAR8

... Also check the gas tube to make sure it's not kinked or obstructed from cutting. A no-brainer but I've seen it cause problems before.

 

[Swift]

Re: BCG not cycling in my LAR8

I also noticed something else and I'm not sure if it's related or just how the large frame ARs work but when you cycle the bolt, right about when the bolt face hits the lands it hangs up a bit before finally seating.

I threw a dummy round in the chamber to see what happens and I had to put the stock against my shoulder and use both hands to pull the bolt open to extract it.

Could this be a tolerance/bolt issue instead of gas?

 

[glocksig40]

Re: BCG not cycling in my LAR8

Check to see if a blown primer might have gotten hung up where the forward part of the bolt meets the chamber. I've had that happen too. It stuck to where I had to take the rifle apart to get the bolt out. Small piece of the primer wedged in when it blew out.

 

[Swift]

Re: BCG not cycling in my LAR8

Ok guys, quick update. Well, not much of an update, really. Still having issues and I've gone through every step that I possibly can to figure this out. I cycled the action 2000 times, lubed it and cleaned it with everything imaginable, blew out the bore with compressed air, cleaned and lubed it some more and still no difference.

The only conclusion I came to is that the machining tolerances between the bolt face/ejector and barrel cam (I believe that's what it's called. Where the teeth on the bolt lock up) are off. Once it breaks looks from that cam(?) it cycles very smoothly and evenly. Should I try a replacement bolt or just find an AR smith?

 

[2ndamendfan]

Re: BCG not cycling in my LAR8

Check the gas key on the bolt carrier and make sure it is not loose. Have seen an AR-15 with a broken gas key bolt that would not cycle. Realy sounds like a gas problem.

As far as the bolt stoping just before it locks up, I can get all 9 of my ar-15's (all different makes) and my LAR-8 to do that if I very very gently close the bolt with the charging handle, just let it go very slowly.

I really think you have a gas problem. I run an adjustable block on one for when I run a can. As some one else stated pull the can off without opening the regulator and the gun will not cycle at all.

 

[ORD]

Re: BCG not cycling in my LAR8

First off...did you ever get in touch with the person who sold it to you? Did he/she have anything to say about the rifle's function while they had it or about the problems you are experiencing? Just wondering how long this problem has been going on and trying to figure out when/where it originated...

With that said, since it has been a couple of weeks and you have tried various different recommended fixes with none of them working, I think it is time for your LAR-8 to make a trip home to Colona and let the boys at RRA figure out what they hell is wrong with it. Their lifetime warranty exists for a reason and if a gun they built won't go bang properly...let them see if they can determine the cause of the problem and fix it for you.

Give them a call and see if they can perhaps give you any guidance/advice over the phone and if not, then get the ball rolling on sending it in. Here's their phone: 1-866-980-ROCK (7625).

If not RRA, then Steve and the magic-makers at ADCO are only about 2hrs west of you in Sylvania. Give them a shout by e-mail and see if they work on the LAR-8 rifles (ADCO is a BIG Rock River dealer, so I am betting they can help you). See here for more info: http://www.adcofirearms.com/

Hang in there!

 

[Swift]

Re: BCG not cycling in my LAR8

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body">First off...did you ever get in touch with the person who sold it to you? Did he/she have anything to say about the rifle's function while they had it or about the problems you are experiencing? Just wondering how long this problem has been going on and trying to figure out when/where it originated...

With that said, since it has been a couple of weeks and you have tried various different recommended fixes with none of them working, I think it is time for your LAR-8 to make a trip home to Colona and let the boys at RRA figure out what they hell is wrong with it. Their lifetime warranty exists for a reason and if a gun they built won't go bang properly...let them see if they can determine the cause of the problem and fix it for you.

Give them a call and see if they can perhaps give you any guidance/advice over the phone and if not, then get the ball rolling on sending it in. Here's their phone: 1-866-980-ROCK (7625).

If not RRA, then Steve and the magic-makers at ADCO are only about 2hrs west of you in Sylvania. Give them a shout by e-mail and see if they work on the LAR-8 rifles (ADCO is a BIG Rock River dealer, so I am betting they can help you). See here for more info: http://www.adcofirearms.com/

Hang in there! </div></div>

Hey thanks for all the insight. I did contact the previous owner and they said that the rifle never had any hiccups. They are a member here so I trust them. I can't imagine it got damaged like that in shipping, though.

Sending it back to RRA is clearly the best option, however what's the turnaround on repairs? Do I have to cover the $847 it would cost to ship it? Or am I better off driving it a couple hours to ADCO? I guess I'll give em a call first.

FWIW, I checked out the gas key yesterday. Staking is pretty good and torque is right where it should be. Check that off the list.

 

[Steelhead]

Re: BCG not cycling in my LAR8

I broke the BHO rod on my LAR-8. (I think it was caused by shooting it suppressed). Anyway, it took a piece of the BHO and shoved it up into the chamber, so I had to send it back to Rock River. I paid the shipping to Rock River, but I had a new rifle back in about 2 weeks.

I think the total of shipping the rifle via UPS was around $28 with insurance, tracking, etc.

Send it in to them!!! You'll have a great shooting rifle in a couple of weeks!

 

[ORD]

Re: BCG not cycling in my LAR8

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: THEBEARRRRRRJEW</div><div class="ubbcode-body">Hey thanks for all the insight. I did contact the previous owner and they said that the rifle never had any hiccups. They are a member here so I trust them. I can't imagine it got damaged like that in shipping, though.

Sending it back to RRA is clearly the best option, however what's the turnaround on repairs? Do I have to cover the $847 it would cost to ship it? Or am I better off driving it a couple hours to ADCO? I guess I'll give em a call first.</div></div>

No problem at all. Just trying to help out where I can. As for the previous seller...I wasn't trying to suggest he did anything wrong or otherwise sold you a lemon. I am just trying to figure when things went awry and what could have possibly caused it. As for it being damaged in transit...I have seen first-hand what the shipping monkeys can and will do to a package (regardless of the contents) if left to their own devices! May have been damaged in transit...maybe not.

As for the S&H thing...it really isn't THAT big a deal. Package it up good in either the OEM shipping container (or a padded shipping case of some variety), then ship it INSURED via RRA's preferred method. Should run you no more than $50 give or take (if anywhere NEAR that much). Depending on what kind of vehicle you drive, it'll cost you less to ship it to RRA than it will cost you in gas to drive it to ADCO. Turnaround for both RRA and ADCO should be a couple of weeks (a month at the very most unless you run into a situation where they need a part that they don't have or can't get in a reasonable timeframe...RRA's proprietary stuff can take some time if it isn't on hand).

 

[2ndamendfan]

Re: BCG not cycling in my LAR8

Well we tried to help. If Rock river fixes it please let us know what they found. That is if they tell you. If you get a new gun out of the deal well then great for you.

 

[Swift]

Re: BCG not cycling in my LAR8

I spoke with a guy at RRA for a few minutes yesterday. Explained the problem. He said one thing he's been noticing a lot lately is that the ejectors can be hard on the brass and people are ending up with flakes of brass wedged between the ejector and the bolt body and preventing it from engaging the rim. I told him that once you manually cycle the action the case flies across the room as it should.

Other than that he didn't have many ideas so I'm gonna clean up the ejector for the hell of it then probably call to get authorization for repair.

It's a good thing Rock River has nice factory cases.