Historical question about gas key staking...

AR/M4 AR General Discussion
1

I’m asking this question purely out of curiosity. It is a history oriented question and has nothing to do with the merits of staking the gas key.

I unequivocally believe in bolt carrier gas key staking and this thread is unrelated to the discussion of it.

A few days ago, I heard a guy say that the requirement for gas key staking originated from a batch of FN BCG’s where the gas key fasteners were improperly torqued and came loose after use.

I was under the impression that the requirement for gas key staking was in place since the late 60’s or early 70’s…well before FN had a contract to produce the hardware.

Answers?

2

I have a Colt Rifle from the 70’s with a staked BCG.

3

Thanks for the reply. I figured as much. Just another gun store myth as far as I can tell so far.

4

That guy wouldn’t happen to sell AR15s with non-staked BCGs would he? Or better yet, assemble AR15 parts guns and sell them?

5

From one of these guys:

When buffers looked like this:

6

I have taken a fair amount of interest in this issue as I have two Bushmasters. You will be told that Bushmaster made some rifles with unstaked keys which I have no reason to doubt. This is presented as a reason you should never buy a Bushmaster. I have examined a couple of dozen Bushmasters over the last couple of years and all had properly staked gas keys. I have examined maybe a hundred other ARs of various makes during that time and all had properly staked gas keys. In other words, I have never seen an unstaked gas key.

7

Not to add to the FUD. but the original requirement that I “heard” for staking was so that Rifleman Joe did not disassemble his rifle to far.

again most likely a myth.

8

Factory staking on Colt model 604 (M16) carrier which puts key staking well back into the 1960’s
Note the square punch shape:

9

Back in the 80’s I handled alot of early model A1’s and they all had staked gas keys. I remember because I had to inspect the dam things after our exercises. This was AF non-security forces squadron so we had all the older weapons.

10

I havent seen a colt without it, but cant swear to the date of adding it to the mil-spec

11

1964 Colt SP-1, first year of production.

This was the second one I’ve owned, and both had a simple strike staking of the gas carrier key.

Inside of the bolt carrier was not chromed either, but the bolts were.

12

Thanks Templar. I love the history behind the rifle. I got a kick out of the Colt advertisement you posted. It reminds me very much of their current SP901 web page.

http://www.coltsmfg.com/Catalog/ColtRifles/SP901.aspx

Advertised as a hunting rifle. Oh, Colt.

13

I attended the Small Arms Repair School at Aberdeen Proving Ground in 1973 and was taught then to stake the carrier key. (The tree punch mark method on the top)

14

Depends on what you’re hunting…

BTW…none of the early staking that has been shown here would be what most switched on people would consider to be adequate.