LR-308 Help

[Jgault]

Hello everyone, I'm in need of advice. I built a lr-308, mainly used 2A armament parts(upper, lower, handguard, BCG). It's one of my favorite rifles but I've had a nagging problem I can't get rid of. Once built the charging handle would come unlatched during firing and hit me in the nose. The ledge for the charging handle latch had been tore up pretty good, emailed 2A and they were great and sent me another upper receiver. I put the rifle back together and switched the charging handle to a raptor and it's doing the same thing again. The ledge for the charging handle isn't as deep as my other rifles but it should hold the latch. I've tried 3 different charging handles with the same result. All 3 show wear on the bottom rails starting half way back the handle, right at the spot where the bcg would be passing over the magazine, and a line of wear on the top edges of the charging handle where it is making contact with the top of the channel. There isn't any wear at the nose of the charging handle(or any wear on the bcg including the gas key) so I don't believe its getting hung on the gas tube. It's not a gas issue, I turned the gas down and it still popped the charging handle loose even with the gas turned down to wear the bolt didn't travel far enough back to lock open. The channel is smooth and there isn't any burrs to hang up on. The upper and lower are well made and literally fit together without any gap. The only thing I can think is causing this now is when the bcg rides over the next round its raising the bcg slightly pushing the charging handle into the top of the channel causing enough friction for the BCG to bring the charging handle back with it. If there is another reason I would love to know, the best solution I can think of is to lightly sand a millimeter or 2 off the charging handle bottom rails and polish, giving the BCG the little bit of clearance it is evidently lacking.

 

[papershredder]

Post up some pics, and if possible, a short video of rifle cycling. That would go a long ways for getting help. One thing that comes to mind is bolt carrier tilt. Which the cause of that might not be easy to diagnose. The round pushing up on the bolt and carrier may just be a symptom of another problem leading to excessive carrier tilting during rearward travel. Notice any extra wear in the buffer tube?

 

[Jgault]

Post up some pics, and if possible, a short video of rifle cycling. That would go a long ways for getting help. One thing that comes to mind is bolt carrier tilt. Which the cause of that might not be easy to diagnose. The round pushing up on the bolt and carrier may just be a symptom of another problem leading to excessive carrier tilting during rearward travel. Notice any extra wear in the buffer tube?

I will try and get a decent video this weekend. No other than the charging handle coming back the rifle runs just about flawless and the only wear I could see anywhere was on the charging handle , the buffer tube and buffer don’t really have any spots of abnormal wear. The only thing I can saw is the fit between the upper and lower is tight, I can remove the pins by hand but it’s a little more effort than my other 308.

 

[Jgault]

Post up some pics, and if possible, a short video of rifle cycling. That would go a long ways for getting help. One thing that comes to mind is bolt carrier tilt. Which the cause of that might not be easy to diagnose. The round pushing up on the bolt and carrier may just be a symptom of another problem leading to excessive carrier tilting during rearward travel. Notice any extra wear in the buffer tube?

Took the lower apart and you were right, there are 2 almost divots on the two bottom corners of the lower. I have a anti tilt buffer tube laying around do I replaced the old one, will this solve the problem or is it a out of spec lower issue? Thank you btw

 

[rpoL98]

question I have is, how good of a job does the latch on the charging handle do in keeping the CH latched? does the hook have enough of a ledge to grip on, or is the recess for the latch hook too shallow? with the upper detached from the lower, and the BCG removed from the upper, CH latched, without pulling on the CH paddles, by gripping the CH main part (shaft, body), can you pull the CH back? i.e. does the latch hook come out of the recess easily or does it hold firm? I have some CH where the anodizing gets rubbed off on the bottom of the CH, but the CH doesn't come out and bop me in the nose when firing.

 

[357Max]

Took the lower apart and you were right, there are 2 almost divots on the two bottom corners of the lower. I have a anti tilt buffer tube laying around do I replaced the old one, will this solve the problem or is it a out of spec lower issue? Thank you btw

Sounds like you have to much over travel on the BCG in the buffer tube. Bolt carrier hits back of receiver & up into charging handle.

The stopper on the back of the buffer should hit the back of the buffer tube before the carrier hits the lower.

The fix is easy. Pull the buffer/spring out & drop as many quarters in as needed to limit carrier travel to .100 max beyond the bolt stop.
Shouldn't cost more then $1.00 unless you've got a miss matched buffer - tube.

If I remember right I've got .50 in mine.

 

[Jgault]

question I have is, how good of a job does the latch on the charging handle do in keeping the CH latched? does the hook have enough of a ledge to grip on, or is the recess for the latch hook too shallow? with the upper detached from the lower, and the BCG removed from the upper, CH latched, without pulling on the CH paddles, by gripping the CH main part (shaft, body), can you pull the CH back? i.e. does the latch hook come out of the recess easily or does it hold firm? I have some CH where the anodizing gets rubbed off on the bottom of the CH, but the CH doesn't come out and bop me in the nose when firing.

it seems to have good purchase, when I pull on the opposite side with a standard handle it takes a good deal of force to get it to unlock without actuating the release handle, but when shooting it’s coming loose about every fifth shot give or take.

 

[Jgault]

Sounds like you have to much over travel on the BCG in the buffer tube. Bolt carrier hits back of receiver & up into charging handle.

The stopper on the back of the buffer should hit the back of the buffer tube before the carrier hits the lower.

The fix is easy. Pull the buffer/spring out & drop as many quarters in as needed to limit carrier travel to .100 max beyond the bolt stop.
Shouldn't cost more then $1.00 unless you've got a miss matched buffer - tube.

If I remember right I've got .50 in mine.

That would actually be my cheapest gun part to date, at this point I’m in the try all of the above category so quarters it is.

 

[rpoL98]

Took the lower apart and you were right, there are 2 almost divots on the two bottom corners of the lower. I have a anti tilt buffer tube laying around do I replaced the old one, will this solve the problem or is it a out of spec lower issue? Thank you btw

yup, BCG is going too far back into the buffer tube. as mentioned above, quarters, or a mis-matched buffer, buffer tube combo.

 

[papershredder]

Took the lower apart and you were right, there are 2 almost divots on the two bottom corners of the lower. I have a anti tilt buffer tube laying around do I replaced the old one, will this solve the problem or is it a out of spec lower issue? Thank you btw

Go with the above suggestions first and make sure the carrier isn't hitting the receiver (fix that if it is). Hopefully that's your problem. If the issue is tilt, then you're looking at potentially trouble shooting tolerance stacking between multiple components. Not fun at all

 

[Jgault]

Thanks everyone for the help, I did throw a few quarters in to stop the over travel so thank you. The problem turned out to be the charging handles. The raptor has a angle that this gun evidently disagreed with, it just didn’t catch flush with the ledge. The spring on the milspec was a little weak. I took a strike handle I had laying around, dropped a slide release plunger into the spring channel to increase the spring tension and all fixed, runs like a champ and I’m not getting hit in the nose anymore.