gas key wobble

[rexican]

I was cleaning my 450 carbine today, and noticed its gas key has developed some lateral play. I only have a couple hundred rounds through this gun, the allen heads are staked well, but I'm worried that the bolt closest to the gas tube has sheared.It's been just over a year since I bought it as an upper; I believe the bushmaster warranty has expired.
Should I go ahead and remove the gas key to check? I figure I'll have to order new screws anyway to tighten it back down. I'll have to pick up something that measures in inch-pounds to re-torque it.

[Texas Sheepdawg]

Once removed, you might as well buy two new screws and gas key. staking is not hard. You can do a search and I would suggest you do so, to confirm the torque on the gas key screws. I have read anywhere from 28-55 Inch pounds. I think military opinions claim the high end while commercial opinions are lower. Do a search and confirm where you want to go.

[wildcatter]

Sounds like you may have sheared a bolt. Give Bushy a call anyways, they just might fix it or at least give you the deal of the Century, for the parts the Dawg-Man described..

..t

[rexican]

Phew, that was a relief. I called bushmaster customer service as y'all suggested and I have a new gas key on the way. As soon as I got off the phone with them, I pulled mine off to find the bolt hadn't sheared.
Now I have no idea how the gas key came loose. The bolts were staked really well and the threads look perfect.
I've thought about going to a full auto bolt for the extra mass, and I happened to get a BCM one in the mail yesterday for a m4 project I just started. Plus, bushmaster bolt carriers just went on sale on brownells.
The curse of the AR: too many options.

[Texas Sheepdawg]

Well as I mentioned earlier, for some reason, commercial opinion on torque vary from military standards.
I am trying to find a link for for you.

[Texas Sheepdawg]

Here is a cut & paste from another forum:

For years, veteran ArmaLite® assemblers have tightened carrier keys using a simple Allen wrench. This process has been successful.

As we added employees we decided to use calibrated torque wrenches to assure that we secure the key screws to the proper level. The government standard for carrier key torque is 35 to 40 inch pounds, and we secured torque wrenches set to that value. We then noticed an INCREASE in loose carrier keys. It turns out that we had tightened carrier key screws better without the wrench than with it. 

The problem is that the government torque values shown in maintenance manuals are too low.

We have examined the engineering data related to the screw itself, and have increased torque to 55 inch pounds to improve carrier key tightness. We recommend that all AR owners make sure that their carrier key screws are secured to this level, especially if their rifles sometimes shows signs of weak or slow cycling.

If your AR “short strokes,” clean the underside of the carrier key and tighten both screws to 55 to 60 inch pounds. Tighten the front screw first. If your rifle isn’t short stroking, just make sure that the screws are tight and restake if needed.

Also found this.
Civilian 35-48 inch pounds
Mil Spec 50-58 inch pounds

[Hoot]

Here is a cut & paste from another forum:

For years, veteran ArmaLite® assemblers have tightened carrier keys using a simple Allen wrench. This process has been successful.

As we added employees we decided to use calibrated torque wrenches to assure that we secure the key screws to the proper level. The government standard for carrier key torque is 35 to 40 inch pounds, and we secured torque wrenches set to that value. We then noticed an INCREASE in loose carrier keys. It turns out that we had tightened carrier key screws better without the wrench than with it. 

The problem is that the government torque values shown in maintenance manuals are too low.

We have examined the engineering data related to the screw itself, and have increased torque to 55 inch pounds to improve carrier key tightness. We recommend that all AR owners make sure that their carrier key screws are secured to this level, especially if their rifles sometimes shows signs of weak or slow cycling.

If your AR “short strokes,” clean the underside of the carrier key and tighten both screws to 55 to 60 inch pounds. Tighten the front screw first. If your rifle isn’t short stroking, just make sure that the screws are tight and restake if needed.

Also found this.
Civilian 35-48 inch pounds
Mil Spec 50-58 inch pounds

How About stickying this post in the soon-to-be-made Reference Material sub-forum?

Email me if you want to delegate that task.

Hoot