You may want to consider whether your guy is old fashion.
The .38 revolver is the old fashion way to go. It also only has six shots, so if he's getting into a big shoot out, it may notbe proper. But the Smith and Wesson revolver is a very reliable gun. in the souped up .357 magnum, your knockdown rate is something like 96%.
If he's a flat out tough guy, you could go with a .45 ACP. These guns can be souped up for speed and accuracy, and what not, but the frame is kind of big and not a great one for concealed carry. I believe the souped up .45 ammo has a 86% knockdown effectiveness.
Then you have .40 and 9mm. The standards are I don't know what's being used by the military now, the Glock, Beretta or Sig Sauer. The Glock is an ugly gun but it is bomb-proof reliable. The Beretta and and Sig are also considered reliable. The .40 and 9mm in souped up ammo (commonly referred to as +p. A company named Cor-Bon makes good ammo) has either a 93% or 96 % knock-down rate. Glocks, Berettas and Sigs would be used by guys with a more military background.
I don't think .380 isn't a great calliber. I've seen a guy take 5 shots in the belly and keep going. But then again, shot placement is everything. If he had been hit in the head as opposed to the gut, he would have been dead.
A lot of us macho guys see guns as a personal way to express ourselves.
I personally use a pea shooter.