Quote Originally Posted by tiriaq View Post
The CMPicon National Match program wants issue appearing rifles, which can be worked over internally, including match grade barrels, bedding, etc. I was referring to the CMP M-1 vintage match, which had 1300 entrants last year. I suspect that this match is for original rifles.
The plunger ejector and counterbored boltface used by AIA are a good way of dealing with a rimless cartridges. The Australianicon .223 and 7.62x39 conversions uses boltheads altered in a similar fashion.
I'm a bit leery of the bolt heads altered by adding a ring silver soldered or brazed to the original bolt face, If a case head blew the ring would be another source of sharpnel.

Empty 7.62X39 cases eject well from my Lithgow action.

If a replacement bolt head specifically designed for the rimless cases were available it would probably sell fairly well.
There are a few machinist that provide aftermarket CNC machined accesories for SKS actions, perhaps one of these small companies would be interested in manufacturing replacement boltheads of various types.
If so some otherwise nearly unusable bolt bodies that have badly worn threads but are numbered to their receiver could be returned to good shooting condition by a new manufacture bolt head threaded a hair oversized for the purpose.