Originally Posted by GRR
No you cannot convert a 39 to fire 10mm. 10mm ammo is too long to fit the frame of a 39.
I personally wouldn't count on any short barreled handgun against dangerous game. Maybe a 4" 44 mag. I would prefer a 12 gage shotgun if I expected to encounter bear or lion.
You are right - I forgot about the shorter case. (The reason why I brought it up was because there are accounts of people successfully converting their 10mm Glocks into .45 ACP. Of course Glock does not recommend it, but it is not very difficult).
Of course, no handgun would be the most effective weapon against a bear. However, unless you carry a rifle or shotgun and can deploy it very rapidly, it does not do you any good. And who goes hiking or camping with a rifle or shotgun? (Not in my state -- unless you want to risk getting shot by park rangers).
The .357 Magnum, the .44 magnum and the 10mm actually do have quite a bit of a track record for self defense against bears. They certainly are better than throwing stones.
The 10mm Glock 20 (while obviously not a primary weapon) is the standard issue sidearm for Scandinavian troops who are serving in areas where they encounter polar bears. Military tests there have shown that the 10mm would be a viable "last resort" defense even against polar bears. The 10 mm G20 is less powerful than a .44 magnum revolver, but it is lighter, has less recoil, and the G20 has a 15+ magazine capacity.
(Somehow this thread got split into two. I can't figure out how to combine them).