Now, the sticky wicket. I don't know if all M12-1 has the aluminum cylinder, but at least some did. Or at some point, it may have been upgraded to a steel cylinder. If, it is steel, you're good to go. With an aluminum frame and tapered barrel, you may want to avoid hot +P ammo. If it does have an aluminum cylinder, then you might want to avoid firing it at all. One or more of the chambers may already be cracked. However, if none of the chambers are cracked and the frame & grips are in reasonably good shape it's worth a bit of money. It's not particularly rare, but it is a bit of oddity. Folks will pay more for an oddity. If the chambers check out ok and you must shoot it, you'd be wise to shoot as mild a 38spl round as you can find. Something like a 148 gr wadcutter (not semi wadcutter). You might get enough money to buy a stronger gun with enough money left over to buy plenty of ammo to practice with.

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