I have a basically standard AK with fixed stock rear trunnion, the rearmost trunnion rivet on one side looks like it was put in a tiny bit wrong, the rivet head squeezed a tiny portion of itself down into the hole at the bottom of it and made a tiny wrinkle where it pushed a tiny portion of the sheet metal of the receiver.

Was thinking I could remove the rivet (best way to do this?), and tap out the tiny wrinkle, then use the same diameter rivet but one with a slightly larger head so it would cover the affected area and not do the same thing as the old one.

Is this a common thing? As it's the first AK i've worked on that has had this. Do they make such rivets and where is a good place to score one? Rivet size? or do I need to measure it?

Any tips or info greatly appreciated!

I don't have an AK but you can drill out the rivet. Measure the hole and the length of the rivet. Go on line and type rivet in the search line. Something should show up. Grainger ,McMaster Carr are good for specialty stuff and even amazon. Or local Hardware store. Can u post a picture?

Those long rivets are the hardest ones to remove.

You'll need to drill about 1/2 to 3/4 of the way thru with a 4mm or 5/32" bit. follow that with a #16. Then hold the receiver on a 2x4 and drive the remainder of the rivet out with a punch. You can drill a hole in the board for the rivet to drive into or just punch it into the wood.

Now you need one of those long rivet jigs to install the new rivet. As far as the larger head, someone else may chime in on that. I use AKBuilder and Bulgarian rivets, none of them are oversize.

Personally id consider not messing with it
There’s a very good chance it will not go as planed and look worse.

The only rivets iv removed were on the receiver stubs that I didn’t care about damaging.
The best way I found for the long ones was to chisel the head off and drill from both sides with an 1/8 drill.

Thanks for the info! Do you happen to know the size/dimensions of that rivet?

An AK Builder rivet is .170"(4.5mm) dia. x 1.600"(40.5mm) to the base of the head. The head is a swell neck with a diameter of .265"(6.5mm).

Metric conversions are approximate.

I've used this tool from AK builder to remove bad rivets from a trunnion in a good receiver for replacement:

Rivet Head Drilling Tool

You just want to take your time and check your work to make sure you are not going off center as you drill.  Drill from both sides.  One or both of the rivet heads can be knocked off with chisel after the center is drilled out, and then as others have suggested, pound the remainder of the rivet out with a punch.

Good luck.

Matt