barrel exchange and SB2 receiver

[mgeorge]

I have an Ultra Slug Hunter Deluxe 12ga. (in about 200), which is an SB2 receiver (from what I can tell on the hr1971 website).  I seem to recall hearing that SB2 receivers can have any barrel (shotgun, rifle, or muzzle loader) fitted to it.

However, the H&R site says that only shotgun bbls can be put on shotgun receivers.

Does anyone here know if the factory will fit a .243Win bull barrel to the receiver of this USHD?

Thanks!

[darat100]

george

the frame that the 12 USH goes on is actually a 10 guage frame.  It is bigger than the sb2 frame.  (I think)  I don't think you can have anything except the 12 USH and a 10 guage barrel fit to it.

[quickdtoo]

darat100 is correct, the 12ga USH frame is an SB2 frame, but it's too big to fit a rifle barrel on it, the chamber swell of the 10ga shotgun and 12ga slug barrels are 1.2XX" in diameter, a rifle barrel is 1.1XX" diameter, that would leave the barrel unsupported on the side when locked up. Other issues are the firing pin size and the larger firing pin hole in the frame, not conducive to high pressure primer performance, shotgun pressures are only 13.5kpsi, compared to pressures of 60kpsi for the 243. The sides of the USH frame are much thinner at the top than an SB2 rifle frame too, which is where the pressure of a rifle cartridge would put the most stress. Those are the reasons why they won't fit a rifle barrel to that frame.

Tim

http://www.frfrogspad.com/miscellk.htm#pressure

[mgeorge]

Thank you for your responses.  This forum is a wealth of information!