AR Sponsor
Posted: 5/28/2011 6:23:57 AM EDT
|
Finally got my AR-10 to run well enough on the bench to go out for a test fire. It has been dry cycled a thousand times on the bench. I went through a couple of magazines with no problem and was very happy with my results
So, then I cracked it open to clean and inspect... I noticed that the Buffer Retainer is taking a real beating. It is bent and looks like it will eventually break. I know the AR-10 has a heavier Buffer Spring. Is there a heavier more beefed up Buffer Retainer for the AR-10? Anyone else seen this? |
|
the buffer retainer shouldn't be under pressure when the upper and lower receivers are mated together.
it's mostly there to keep the buffer from flying forward when you open it up. on an AR style rifle, the bolt carrier should kiss the front of the buffer as you close up the upper and lower, just enough to take the pressure off of the retainer and then, when fired, it all reciprocates like together. is it a factory armalite rifle? or are you saying 'AR-10' in a more general sense? |
|
I said AR-10 cause it's an Armalite type rifle, but it's not factory... It's a parts gun I built from scratch.
That is good info! Now I am thinking that maybe I damaged it early in the build (before firing) because the upper receiver and lower receiver didn't fit together very well at first. Thanks for the tip, now I know what to look for as I replace the old buffer retainer! |
|
if you have another AR-type rifle to take a look at, open it up and notice how the bolt carrier makes contact with the front edge of the buffer as you close it together (or should make contact).
that little pin is definitely not designed to take the force of the reciprocating buffer. |
|
On my ar10 the bolt contacts the buffer face just as the bottom of the upper's rear lug is flush with the top of the lower.receiver. When fully closed and pinned the buffer is pre loaded about .035.
I have seen this on AR15's and it is caused by the buffer retainer hole being out of spec. Replace the lower, or I have seen a lip machined around the face of the buffer for added clearance from the buffer retainer.. |
|
If the lower is out of spec ,for a band aid, you can use the Tubbs CWS (I think ,Superior Shooting Systems ) to add a little to the end of the bolt carrier to keep that from happening .
Its a weight system, where you can add different sizes to slow the BCG down , but it adds to the length of the BCG , a little & has helped others . This is not the first to have this problem . Been seeing more on a regular basis ,lately. There could be other things causing your pin & buffer to be damaged. |
|
Quoted:
I noticed that the Buffer Retainer is taking a real beating. It is bent and looks like it will eventually break. Anyone else seen this? Pics, of the edges of the actual buffer, please. If the buffer retaining pin is beat that bad, then the edges of the buffer should be pretty bad off. If you can get pics of that up, it will help. Anyone else seen this? - yes, I have, on one of my guns. What exact brand of upper and lower are you running? "AR-10 type" isn't specific enough, based on problems from certain manufacturers. You need to give up the details if you want help from the people that have had problems. |
|
Pics, of the edges of the actual buffer, please. If the buffer retaining pin is beat that bad, then the edges of the buffer should be pretty bad off. If you can get pics of that up, it will help.
What exact brand of upper and lower are you running? "AR-10 type" isn't specific enough, based on problems from certain manufacturers. You need to give up the details if you want help from the people that have had problems. THIS^^^^^^^^^^ Another thing to look at is the bottom rear of the bolt carrier, the area that rides over the buffer retainer. |
AR Sponsor