OK, so if a guy decides to do this, the smart play would be to use a SB2 receiver, RIGHT?? Using the adapter doesn't change the physics of the bullet pressures so in order to be safe, you would still want rifle calibers being fired from the SB2. RIGHT??
I wonder just how accurate these things are?? Hmmm....SB2 with a 12ga barrel shortened to 181/2", w/rifle sights or a scope, 18" adapter, HMMMM?
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That could be a very economical and effective firearm. You could shoot just about anything through it.
Food for thought....
cookiemann