Caliber for Concealed Carry

Question
I have owned a Kahr PM9-9mm for less than a year. The size and weight are ideal for concealed carry, however, the firearm is very unsatisfactory as far as any accuracy. It has been sent back to the factory for an ejection problem. Now, after approximately 3000 rounds it can not even be sighted in as the barrel appears loose.

Therefore, I have decided to switch to a Glock 27.

My question is, in your opinion, which is the best caliber: 9mm, 40, or 45.

Thanks for your time.

Tom Kennedy

Answer
Mr. Kennedy,

If you have decided on a Glock 27, then you've already picked your caliber - .40 S&W.

You can get the same sized gun in 9mm, but it would be a Glock 26.

If you want a compacy version in .45, your choices would be the Glock 30 (considerably bigger than the 9/40 frame) or the Glock 36 (there are some feed problems with the G36 magazines).

No handgun is a good stopper.  Data is ambiguous, but the best stoppers of a poor lot seem to be in the premium .40 ammunition, so my choice would be (and is) the G27 for a compact gun.

With premium ammunition, however, the 9mm is not a far second, and there are considerations other than caliber.  For me, the unreliability of the G36 and the too-large grip circumference of the G30 would make the G27 and G26 my first and second choice respectively.

I am both surprised and sorry to hear about your experience with Kahr.