AR Buffer Tube assembly Question

[SC_Chewy]

Well I took my AR out to Rancho Cordova Rifle range and started to sight in my scope, got through about 8 shots and she jammed up. At first could not even open it up to investigate. Asked R/O for assistance and he got it open. Looked in and the detent from the buffer assembly is jammed into the bolt group. He informed me I had not put it together right. I torn it down, screwed in the tube part way, put the spring/detent back in, tightened the tube, then fed the spring and buffer in, depressed the detent, pushed them in the rest of the way and reassembled the stock. Fired off aboout 10 more and bam, same deal. When I took it apart the second time I noticed the tube had lossened somewhat. Took my time, refered to manual to double check instructions and put it back together. Finished shooting without incident but the problem is still bugging me and I When I was putting it back together I noticed that the end of the buffer tube is flat on 2 sides as if to allow you to put a wrench to it and tighten it further. My question is this, am I not tighting this enough (as hard as as can with hand) and I need to wrench it down (doesnt seem like I should) or should I just see if I did it right and wait to see if it jams again. Thanks for any assistance and to the R/O at Cordova for his patience.

[TonyM]

You should not have to press down the spring/buffer retainer. Sounds like you didn't screw the receiver extension(buffer tube) in far enough. Here's a picture of it installed correctly:



Notice that the tube is holding the retainer down into the hole in the lower. If you are using a collapsible stock, make sure you torque the nut down to prevent it from backing off.

Here's a complete set of instructions from ar15.com:

http://www.ar15.com/forums/topic.html?b=3&f=4&t=226782

[grywlfbg]

Is it an A2 stock or a carbine stock? IMHO, the carbine stock is much easier to deal with as it's a very simple tighten the castle nut down w/ the wrench. The anal could put a drop of light or medium loctite.

The A2 stock was a major PITA. Trying to keep the takedown pin detent spring in place while screwing the stock on sucked. The other thing to remember is that after you screw the stock on you need to crank down the upper screw on the back of the stock to tighten everything up. There will be some slop if you don't.

Chris

[SC_Chewy]

Thanks for all the help. I am tearing it down right now. Really enjoyed shooting this gun and this site is a great resource. Awesome.

[MrLogan]

What, specifically, type of torque wrench do I need to properly tighten an A2 stock buffer tube?

[TonyM]

What, specifically, type of torque wrench do I need to properly tighten an A2 stock buffer tube?

I never used a torque wrench of any kind.

I go "snug" the just a little more. Just don't bust out an impact wrench set to 200lbs. and go nuts!

[MrLogan]

I never used a torque wrench of any kind.

I go "snug" the just a little more. Just don't bust out an impact wrench set to 200lbs. and go nuts!

lol

So I take it you just hand tightened, and that's all? No problems with it loosening up later on?

[TonyM]

lol

So I take it you just hand tightened, and that's all? No problems with it loosening up later on?

On my A2 stocks I just used my combination barrel/stock tool to snug it up using the flat ends at the end of the buffer tube. With the Carbine stock and LMT SOPMOD stocks I used the same tool for the nut.

This is the tool I've used for years:

[xenophobe]

For a standard receiver extension all you need is a crescent wrench. Just assemble it correctly and hand tighten. Then grab the crescent wrench and tug it slightly tighter. No locktite necessary and it will not move.

If it is a carbine receiver extension, you need to assemble it correctly, and then tighten down the castle nut tight and stake it.