I am about to remove a buttstock and install a collapsible looking butt on my AR.  I heard of stories where folks had a hard time.

Can anyone lead me to a post with instructions on how to do this right?

TSL

Unload rifle (duh), separate upper from lower.

Remove the upper screw from the butt of the A2 stock.  Slide the whole thing off and set aside.  When you do this, there is a spring held in the back of the receiver by the buttstock and presses against the rear pin detent.  Don't lose the spring or detent, as you will still need these.

There will be a short spacer left either on the end of the buffer/ receiver extension, or down inside the stock.

Push down the buffer detent, and remove the buffer and its spring.  The buffer and buffer spring will not be reused on this rifle.  You will reuse the buffer detent and its spring.

The end of the receiver extension has flats to put a wrench on.  Hold the receiver firmly, and unscrew the extension.  As you unscrew it, the front edge will back off of the buffer detent and free it up for removal, along with its spring.  Set these aside, you still need these.

Your new receiver extension will have a little plate shaped like the back end of the receiver, with the round nut, or ring holding it on the tube for shipping purposes.  Remove the lock ring and nut, and replace the lockring, screwing it all the way back, you need some working room.

Note how the little plate fits on the back of the receiver, and in turn, holds the spring and rear pin detent.  Thread the receiver extension in with the plate positioned properly, stopping just before receiver extension begins to cover the hole for the buffer detent.  Insert the spring and detent.  

Apply little "Service Removable Locktite" to the threads of the extension, where it is about to thread into the back of the receiver.  Do NOT put any Locktite on the inside of the receiver, as it will be pushed ahead and gum up the buffer detent.  As you begin to thread in the receiver extension the last few turns, you must hold the buffer detent down.  Screw in the extension so that it almost touchs the pin on the detent.  Get the tube in the correct vertical position.

Make sure the rear pin detent and spring are in correctly, push the little adapter plate forward, and apply a drop of Locktite where the lockring will tighten.  Snug the ring up with the wrench or spanner made for this stock.

(If you do not have this tool, you can make it up by hand as well as possible, then, having another person hold the receiver, tap on the hole or notch on the lock ring lightly with a punch and small hammer.  Just a few taps will do, the Locktite will do its job here.)

While the Locktite has still not set up yet, check that the stock is aligned properly with the receiver.  Check that the buffer detent works freely, and the rear pin is snapping open and closed correctly, that the rear pin detent is working as it should.

Done.

A2 STOCK



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PARTS: takedown pin, takedown pin spring, takedown pin detent, stock, buffer extension, retainer, retainer spring, buffer, buffer spring
TOOLS: #10 (or larger) flat-blade screwdriver

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Insert retainer spring and retainer into recess in lower.
Install buffer extension, (buffer tube); press detent when necessary; torque to 35-39 ft-lbs add spacer onto stock tube, and insert stock.
Install takedown pin with groove to the rear and install detent and spring from the rear of the receiver.
Carefully compress the spring with the stock and secure the stock in place with the self-locking screw.
Insert stock screw from rear into stock.
With hammer down, insert buffer spring and buffer into buffer tube until retainer snaps up to lock it in place.
Function check on takedown pin and buffer retainer.

TELESCOPING STOCK



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PARTS: takedown pin, takedown pin spring, takedown pin detent, telescoping stock, buffer extension, backplate, locking ring, retainer, retainer spring, buffer spring, buffer

TOOLS: Telescoping Stock Wrench

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Insert retainer spring and retainer into recess in lower.
Install buffer tube, backplate, and locking ring onto receiver and depress retainer when necessary to get it to rest under the extension tube. Turn tube until it is about 1/4 turn past the correct location.
Install takedown pin with groove to the rear and install detent and spring from the rear of the receiver.
Backplate will now hold spring in place when you turn the extension tube back 1/4 turn.
Tighten locking ring using telestock wrench for a snug fit.
With the hammer down, insert buffer spring and buffer into buffer tube until retainer snaps up to lock it in place.
Function check takedown pin, stock, and buffer retainer.
 
 

TM 9-1005-319-23 (2.6MB PDF)
Unit And Direct Support Maintenance Manual M16A2, M4, M4A1

old.ar15.com/books/TM9-1005-319-23.pdf

Ask and ye shall receive,

Thanks,
pictures will be posted soon.

TSL