LR-308 issues

[kalieracer]

Did you get the buffer too, I had recommended that you the complete set.

Darn it! I was able to squeeze in some range time. Unknown if problem is fixed I have a new issue. But this I may know what the problem is (I think). Now the rounds wont fully eject. Prior to new fix they did eject fine, just did not chamber next round, and the bolt would never lock back after last round fired.

I think after installing the Armalite tube extension and using the Armalite spring, that the spring may be to strong or long. Even thought it did fix the issue of the bolt catch can lock on to the front of the bolt. I can feel that this spring is stronger.

So I think I can squeeze in another range day tomorrow. I am going to switch back to my old spring, and lube up the bolt and BCG (I did not have time today). I am also going to cycle it as much as I can.

I hope that does it. If not, back to the drawing board I guess.

I wish I had more positive news, but I guess the only positive is, I may be able to correct this new issue.

I will update tomorrow

Thanks
Jay

[lwbyo1]

Yes, I have a short 308 buffer that I am using, not the long AR-15 type. I am not sure on the old tube, could be for AR15 or I think its for a different type of 308 build. (not for the LR-308)

I hope you're not using the short LR-308 buffer with the longer AR10 buffer tube. If you are, you're going to damage your lower. The short LR-308 buffer is used if you're using an AR15 buffer tube on an AR10/LR-308 rifle.

If you're using the AR10 buffer tube, you need to use the AR10 buffer (AR15 H3 buffer) and AR10 spring with it.

[hundy]

I hope you're not using the short LR-308 buffer with the longer AR10 buffer tube. If you are, you're going to damage your lower. The short LR-308 buffer is used if you're using an AR15 buffer tube on an AR10/LR-308 rifle.

If you're using the AR10 buffer tube, you need to use the AR10 buffer (AR15 H3 buffer) and AR10 spring with it.

I am not. I am using my short LR-308 buffer, but the tube is a carbine tube that is slightly longer than the one I had, its not a rifle tube. You can read below the results

Did you get the buffer too, I had recommended that you the complete set.

I did not get the buffer, but you will see below what happen.

Okay, so are you saying that the bolt would try to eject the spent case, but would not move back fully to let the brass fly out? You did not mention any double feeding, so I assume the bolt does not move back far enough to try and feed/push the next round?
Sounds like now you're not getting enough gas. Could it possibly be your gas block moved out of position when you stripped the screw, when you try taking it out?
What is the clearance between bolt face and bolt catch when you pull the CH all the way? I think there should be about 1/4".
Do not put the old spring back! remember you have a longer tube. The old spring was from an LR308, which is shorter, correct? If so, then your carrier can move too far back and damage the receiver. Stick with the new spring and check your GB/tube.
My LR308 carbine spring is also too stiff/strong. It still is even after 200 rounds, but my rifle functions flowlessly using ZQI and my reloads.

I get what you are saying. but this spring was a lot longer and really added some stiffness. I am not using a rifle tube, it is a extended carbine tube. I put the old spring back. I did lube the heck out of the bolt and BCG, and I cycled it about 50 times.


The Result is that its fixed, it finally works. I put the small LR-308 buffer and spring in the extended carbine tube. I also lubed bolt and BCG again and I cycled it about 50 times.

It fired, ejected, and chambered a round every time. At the end I put 10 in the magazine (I had been only doing 3) and it worked great. I checked the BCG and all lower and upper parts no ware or damage seen.

Finally after several fixes and trips to the range, I have a fully functioning LR-308. Thank you for all the help.

I am very grateful for this group and site.

Jay

[Redeyedrider]

I'm glad to hear it. I can't stand to have a malfunctioning firearm sitting in my inventory! It drives me nuts until I know that I can grab it out of the safe and run it reliably.

[97F1504RAD]

Glad to see that what i told you to do worked and seems to have resolved your issue along with the things you swapped.

I know exactly what you were going through and kept checking and double checking all my work and it just did not add up.

That why I decided to cycle by hand about 100 times and lube the crap out of the BCG and began firing again and after a few mags worth of ammo it finally began working.

It is the complete opposite of the AR's I have built they worked flawlessly right from the start.

[lwbyo1]

I hope you're not using the short LR-308 buffer with the longer AR10 buffer tube. If you are, you're going to damage your lower. The short LR-308 buffer is used if you're using an AR15 buffer tube on an AR10/LR-308 rifle.

If you're using the AR10 buffer tube, you need to use the AR10 buffer (AR15 H3 buffer) and AR10 spring with it.

I am not. I am using my short LR-308 buffer, but the tube is a carbine tube that is slightly longer than the one I had, its not a rifle tube. You can read below the results

Sorry hundy, I'm a little confused by your reply. You said you're not using the short LR-308 buffer, but then say you are. I think you may be getting the different buffers confused.

With the longer AR10 buffer tube (approx. 7-5/8" internal measurement), you MUST use the longer AR15 buffer (3-1/4" long). If you're using the short LR-308 buffer (2-1/2" long), you're going to damage your lower receiver. You should measure your buffer and see which one you're using.

I'm thinking you were using an AR15 buffer all along. That would explain why the BCG would not go back far enough behind the bolt catch when you were using the AR15 buffer tube and why you aren't seeing any damage to the lower after firing it.

Let us know what you find.

[gemini1]

^ Im also confused with his response. But at the end of the day, its nice to hear you got it working. However just as lwbyo1, Im interested to know what length your buffer is. The rifle is definitely not gonna work correctly if you use a longer carbine tube (used in AR10) and a short buffer (used in DPMS). The longer tube, uses buffer like the one on an AR15.

[hundy]

Sorry hundy, I'm a little confused by your reply. You said you're not using the short LR-308 buffer, but then say you are. I think you may be getting the different buffers confused.

With the longer AR10 buffer tube (approx. 7-5/8" internal measurement), you MUST use the longer AR15 buffer (3-1/4" long). If you're using the short LR-308 buffer (2-1/2" long), you're going to damage your lower receiver. You should measure your buffer and see which one you're using.

I'm thinking you were using an AR15 buffer all along. That would explain why the BCG would not go back far enough behind the bolt catch when you were using the AR15 buffer tube and why you aren't seeing any damage to the lower after firing it.

Let us know what you find.

^ Im also confused with his response. But at the end of the day, its nice to hear you got it working. However just as lwbyo1, Im interested to know what length your buffer is. The rifle is definitely not gonna work correctly if you use a longer carbine tube (used in AR10) and a short buffer (used in DPMS). The longer tube, uses buffer like the one on an AR15.

Sorry, after reading everything again I can see where it is confusing. I think I initially misread what you posted. but I see now how I basically answered yes and no to the same question.

Originally when this all started I had a short carbine tube, with that tube and the small buffer approx. 2 1/2" when I pulled the bolt back, the bolt catch would not catch in front of the bolt. It actually caught the BCG and you could see the bolt head through the ejection port.

At this point the rifle would fire and eject the round no problem, it just would not chamber or load the next round.

So after several fixes (fixes other than buffer tube) and checking gas block multiple times, nothing worked. Then I ordered the buffer tube with the internal dimension you had stated above. (7 5/8 I think), I keep the original buffer (the smaller one) I also got the armalite spring that was advertised as use in both the carbine tube (7 5/8) and rifle tube. That spring was a lot stronger than the one I had previously. When I went to the range, the rounds would not even eject, I am sure it was the tension from the spring.

So I replaced the new spring with the original one that is slightly shorter. I also used the shorter buffer. The rifle worked flawlessly. I remember reading something similar on another thread on this forum on using shorter buffer on AR10 with that extension tube. So I did check all the parts for wear and marks.

But based on what both of you stated, I may see if I can locate the longer buffer. My only fear is this. The new tube is approx a inch longer than the old one. With the old one I was unable to pull my BCG/Bolt all the way back to have it catch with the bolt catch. So the new buffer is approx a inch longer than the old one. So I am worried I may have the same problem.
So I am going to see if I can borrow one from a friend before I buy one. I know they are not that expensive, but, I have spent a lot of money the last two months to finish all my projects before all the new laws come into effect. I am walking a fine line with spending and keep wife happy right now.

Thank you

Jay

[Junkie]

So you swapped for both a longer tube AND a shorter buffer? I think you may have gone too far, I was under the impression you only wanted one of the two. I could be wrong though. I'd make sure your BCG isn't traveling too far and damaging the receiver in front of the buffer tube.

[hundy]

So you swapped for both a longer tube AND a shorter buffer? I think you may have gone too far, I was under the impression you only wanted one of the two. I could be wrong though. I'd make sure your BCG isn't traveling too far and damaging the receiver in front of the buffer tube.

I did check the receiver thoroughly today I did not notice any damage or marks. I did get in contact with someone who is going to loan me a 3 1/4" buffer so I will try that and see what happens.

I just want to make sure we are all talking about the same thing. I did not get a rifle tube, I got a carbine tube extension. (Armalite) The outside diameter is 8", their rifle buffer tube is 9 11/16". When I say longer buffer tube, I don't mean I got a rifle tube to replace the carbine tube. I got a carbine tube extension, approx. 1" longer than my original carbine tube, but shorter than a rifle tube. I only add this to make sure we are all on same page. But that said a 3 1/4" buffer is on its way, and I don't really have time to go shooting again before it arrives. I will let you know what happen.

Thanks

Jay

[Junkie]

I understand what you mean. My impression is that you had to do one or the other (longer tube OR shorter buffer), not both... but I haven't dealt with it yet and could be wrong.