Take a look at the neat bolt for the Franklin 17 WSM AR.

[22boomer]

Just thought you would like the design work that went into the Franklin Armory 17 WSM AR bolt. The firing pin is designed to rotate with the bolt so it is in the correct position when the bolt locks in place. The bolt itself is very similar to the standard AR bolt and probably has more strength then necessary. The other big obstacle is making magazines for a special cartridge and they have that done also. I didn't read the whole thread so I'm not sure if the magazine can operate the bolt-hold-open. My only problem is the fact that ammo seems to be easily available right now but being a rimfire I wonder how long that will last plus the rifle costs an arm and a leg.

www.rimfirecentral.com/forums/showthread.php?t=586402&highlight=Franklin+Armory+17+WSM+AR