Hello all,

I'm looking to get my OOW '74 receiver back from hardening at AK-USA soon. I'm wondering what you guys have experienced in building on hardened receivers . . .

I'm especially concerned about punching the sheet metal down into the countersinks in the trunion. According to several posts that I have seen on this board, this is not possible with hardened receivers. If so, how are Randy @ Independence Arms or Chris @AK-USA riveting their AK's?

Does anyone have any experience with this issue?

I would LOVE to hear from Randy or Chris

Disconnector

Quoted: I'm especially concerned about punching the sheet metal down into the countersinks in the trunion. According to several posts that I have seen on this board, this is not possible with hardened receivers. If so, how are Randy @ Independence Arms or Chris @AK-USA riveting their AK's?

It's all in the hammer.  If yours is big enough, it will be no problem.  Size does matter.

Make sure you have a BFH.

I read that the BFH hammer method was splitting the metal around the holes when countersinking hardened receivers.
And for that reason, just spot hardening the axis holes was a better option.

Doesn't the OOW come already spot hardened?

Probably not hardened correctly, or more accurately, not tempered correctly.  There is no reason why rivets would not work properly if the receiver is within spec as far as hardness.

All commie receivers are built in with hardened receivers, so it should certainly be doable.

take care,
Tec

<Make sure you have a BFH>

LOL . . . does a 20 ton press count?  

You're probably right about incorrect tempering.  I'll let you guys know what I find out when I call Chris.

Disconnector

Spoke to Chris at AK-USA and he said that if the receivers are PROPERLY hardened, then the metal should countersink when the rivets are installed with no problems.

RC 36-38 isn't really that hard, he said.  Any cracking is the fault of improper heat-treating.

So, it looks like this is a non-issue . . . thank goodness :)