AR-15 Buffer Retainer problem

Olympicarmsfan · 07-25-2008, 11:08 PM

Hi all as some of you know I just finished my kit build. I was showing my cousin the AR and the charging handle was pulled back and slammed home. He put the mag back in the gun and when I got it back to put it away I checked the gun to make sure it was safe no live ammo.

I pulled the handle and it wouldnt come back. I thought well maybe the buffer spring came out or something so I took it apart and saw the problem.

The Buffer Retainer is bent and missing the bottom its now hollow. The spring was jammed inside it and was hitting my charging handle. I know when I put the buffer spring in it was a solid piece. I emailed the company just a few min ago and will see if they send a replacement if not I will just get one. Im taking this to my gun smith to have checked out as well.

My question is should the buffer retainer be hollow and has anyone had this type of problem before?

kernelkrink · 07-26-2008, 12:36 AM

The buffer retainer is supposed to be hollow, the spring fits inside it. The buffer tube should retain it in it's hole, if it came out too far the bolt carrier would hit it and possibly bend or break it. That's what the groove in the bottom rear of the carrier is for, to clear the retainer.

If you have a fixed stock on it, the flange should stop it in the proper spot. The collapsible buffer tube, OTOH, can be screwed in too little and allow the retainer to pop up too far.

Olympicarmsfan · 07-26-2008, 12:40 AM

Thanks for the reply. This is a six postion stock so im thinking maybe I dont have the stock in all the way or in far enough. The stock stops and wont let me get it all the way in. I still have threading that dosnt go in to the receiver. Im going to take it to a gunsmith and have it checked any way so I will just have him put a new one as this one is bent. I could have swore it wasnt hollow but I was wrong. Thanks.

moleman · 07-26-2008, 02:33 AM

The Kernel is correct. The buffer retainer is hollow on the bottem to allow for the spring that pushes it up. The top of the buffer retainer pin should sharply reduce in size and create a shoulder for the buffer tube to keep it from comming out. Some times the threads on the collapsable stocks aren't timed correctly and in order to have the stock positioned correctly either too little or too much of the buffer tube retainer pin is covered. If this is the case then just screw in the buffer tube so that the stock is correctly positioned and the smaller area of the retainer pin (that would normally stick up) is covered by the buffer tube. Mark where the pin should be. remove the buffer tube and make a small half moon so that the buffer tube retaining pin head (the small part) can stick up to catch the buffer. When I have run into that in the past that is what I did, and I have seen a factory DPMS gun that came that way also. Oddly enough I have one of my hunting buddies guns that needs this done as the pin keeps comming out too far. Heres a picture of the bad set up. It doesn't look too bad in the photo but the buffer isn't pushing on it at the time. Give me a few minutes and I'll get the after photo up.

moleman · 07-26-2008, 03:06 AM

Heres a picture of what I was talking about. Just don't screw in the buffer tube far enough that it sticks out of the top of the threaded hole. I actually removed a little more metal than I wanted but it has a much better hold of the pin now.

Olympicarmsfan · 07-30-2008, 01:37 AM

Im got it fixed but im taking it in to a smith to have it looked at cause I dont think the stock fits in far enough it also may go in further if I had a wrench to tighten the stock. I want to get it checked out more.

moleman · 07-30-2008, 10:50 AM

The stock buffer tube should turn in without any real resistance until it is stopped by the small head part of the buffer retainer. The nut at the back is then tightened up with a wrench to hold it in place. There is usually 3/8"-1/2" of unused threads showing behind the stock nut. The purpose of this is so that you can back off the nut to allow the retaining/positioning plate to rotate into position and then push in the rear take down pin spring before you snug down the bolt.

MDG · 07-05-2009, 10:22 AM

That was my problem with jamming and misfiring. The buffer retainer kept coming out of the hole while I was shooting. It would get jammed in the lower and cause problems. Now it's bent all to he!!. Is there a special wrench to tighten the nut that secures the buffer tube at the back?

moleman · 07-05-2009, 11:16 AM

There's two different types of wrenches depending on what type of nut you have. The older style nut just has a hole in the center for a standard spanner type wrench. The newer style nut has 4 notches set 90 degrees apart that are open at the back like in the above photo. You can use a spanner type wrench on both styles of nut. If you have the newer style nut its best to get the correct m-4 style spanner wrench that contacts 3 of the notches in the nut and not just one like the standard spanner wrench. Its also a good idea to put a drop of REMOVABLE locktite on the threads.

MDG · 07-05-2009, 11:38 AM

I have a notched nut. I assume this is what you are referring to.

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