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View Full Version : A2 buttstock screw problems -- non MIL-SPEC?/cross-threaded


HK&1911
09-08-2008, 5:10 PM
Last month I bought an A2 buttstock assembly and am just now getting around to installing it (been pretty busy). I was told it was MIL-SPEC and didn't open and look at it because it was sealed and thought "no problem".

The buttstock screw requires a 5/32 allen key not a flat blade screw driver and it was started cross-threadeds, so I need to find out what it's supposed to be, so I can get a "tap" screw and repair the edge of the hole.

In addition, there are no holes in either screw. Isn't one of them supposed to have a hole in it?

I feel kind of stupid not looking over it. Any help would be appreciated.


HK&1911

bwiese
09-08-2008, 5:36 PM
A milspec A2 buttstock screw uses a flat-blade screwdriver, not a hex key, and has a drain hole.

If you found another hex key buttstock screw and liked it for some reason, fine - as long as it has a drain hole.

HK&1911
09-08-2008, 6:13 PM
Bill:

Thanks for your help. NO, the screw doesn't have a drain hole in it.

Do you know if anybody in the Bay Area have these screws?

Thanks,

HK&1911

bwiese
09-08-2008, 7:39 PM
I'd imagine the boys at Gun Exchange in San Jose or Irvington Arms in Fremont might. Frank Tabor might have one too in the parts bin (Tabor's Guns/San Bruno.)

bohoki
09-08-2008, 8:34 PM
if all else fails

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=489724&t=11082005

HK&1911
09-08-2008, 10:12 PM
I'd rather not purchase a new tube, etc. Since the stock assembly was purchased from a "Calguns" banner advertiser. It was sealed until this evening.

I'll see if they will provide me with the screw. I believe the stock, tube etc. is ok. I was a little miffed when I saw a screw requiring an hex key, was cross-threaded on the 1st & second thread and no drain hole. I've been so busy that I didn't have time to check it out sooner. Grrr. Oh well, I should have installed it as soon as I got home!

Thanks for all your help.

HK&1911

NeoWeird
09-08-2008, 10:38 PM
Not to question you, but are you SURE it was cross threaded? The lock-tite on the screws can be VERY tough to turn sometimes and it can seem like it's not being threaded in right.

Also, the drain hole is CRITICAL. Without the drain hole you will essentially make a pneumatic piston with no valve, so as you fire you will get short strokes as the pressure builds in the buffer tube as it gets compressed with the rear moving buffer. It NEEDS to be there, if you're screw doesn't have it, get rid of it and get a new one.

HK&1911
09-09-2008, 6:01 AM
Thanks for verifying. It wasn't loctite. When I opened the package, I tried to remove the screw by hand and couldn't. Located a hex key that fit and unscrewed it.

At first I thought it was Loctite/Nylok, but it wasn't. The first two threads are sporting that "shiny/mashed" look.

I thought the hole was important--- where are all those gases going to go? :rolleyes:

Thanks again,

HK&1911

StoneTower
09-09-2008, 8:24 AM
Not to question you, but are you SURE it was cross threaded? The lock-tite on the screws can be VERY tough to turn sometimes and it can seem like it's not being threaded in right.

Also, the drain hole is CRITICAL. Without the drain hole you will essentially make a pneumatic piston with no valve, so as you fire you will get short strokes as the pressure builds in the buffer tube as it gets compressed with the rear moving buffer. It NEEDS to be there, if you're screw doesn't have it, get rid of it and get a new one.


I have read that unless you are going to dunk the gun in a lake or river the drain hole is NOT critical. That hole is so small and could not relieve the pressure as fast as the buffer cycles. You will notice that buffer has flat sides on it so that is does not act like a piston. If that little whole was releasing the pressure (and not the flat sides on the buffer), it would probably shoot a whole in your shoulder like the old air injection (immunization) guns they used in the military so that they did not have to change a needle.

Maybe someone like Randal will chime in.

David

ar15barrels
09-09-2008, 8:55 AM
Also, the drain hole is CRITICAL. Without the drain hole you will essentially make a pneumatic piston with no valve, so as you fire you will get short strokes as the pressure builds in the buffer tube as it gets compressed with the rear moving buffer. It NEEDS to be there, if you're screw doesn't have it, get rid of it and get a new one.

Sometimes you make me laugh. :rofl2:

The drain hole only matters if you are walking through streams, rivers and lakes before you shoot your rifle.

It is NOT a significant vent of air.
If you look at the buffer's head, you will note that there are 3 flats milled on it.
THAT is where all the air escapes around the buffer during operation...