While my SOCOM300-SPS was in jail, I spent the time accumulating adapters for various rifles, one of which was SureFire's AK adapter. When I got my stamp and it was "official", I started mounting the adapters. When it came to the N-PAP, I ran into two issues:

1) There is a gap between the back of the adapter and the FSB, because the Yugo's have a slightly longer threaded muzzle.
2) When I put the shims in the adapter, they do not center, as the inner diameter of the adapter is larger than the outer diameter of the supplied shims, giving them room to move.

The first issue seems to be more cosmetic than anything so I'm not really concerned about it, but the shims shifting around did bother me. I contacted SureFire tech support and they shipped out another set of shims, same OD/ID, but instead of the "A" they were marked "B". No difference of course in the issue. Tech support said to use an alignment rod when I mounted the adapter and the shims wouldn't shift, but it really still bugged me, and I checked the shims today after trying to time it and I could see where they were being crushed unevenly due to the difference in diameters and the shifting. So I took the adapter and threaded it on without the shims, torqued it down, and it's aligned perfectly with the alignment rod, but it's obviously not indexed correctly.

So this leads me to the first question; does it matter that the adapter is indexed exactly with the pin at 6 o'clock? All things being equal, the only benefit I can think of is muscle memory in manipulating the lever when taking it off. If there's no real difference, I think I'll just mount it as it, without the shims.

Second question is about the shifting shims. I also have one of the FAL adapters, and when I put the shims in they are good to go and center right up with no shifting at all. Why would the AK-47 adapter/shims be any different in that regard?

I happened to have the similar set up. SF SOCOM300SPS on a Century Arm RAS-47.

I would say the gap is not a problem, the notch does not have to be at the prefect 6 O'clock position.

What matter is before you apply the Rockset thread seal, make sure the suppressor alignment rod is centered on the opening which you already done.

7.62x39 round is slightly bigger than 7.62, about 7.92MM, so you really want the opening to be concentric with the barrel, or else possible baffle strike.

Where did you get FAL nuzzle adapter? I thought it is a group buy with min order.

Thanks for the info. The mount lines up great with the alignment rod so no worries.

I got the FAL mount from OpticsPlanet.