I did try to use the search feature, but came up empty (possibly due to the grossly outdated browser on my work computer); so if this has been addressed, I sincerely apologize.

Lately, I've become intrigued by pistol caliber carbines. I'm not really sure why. I've tossed around the idea of building one, but I don't want to put anything into something for which I'm not going to have a purpose. So, what are the benefits of having PCC vs standard SBR or the like? I've been trying to think of a situation or circumstances where it would be better to have a pistol round than a rifle round, but I'm coming up short. Like I said, I have limited experience with PCCs, so I'm not certain of which applications would be better suited to them than SBRs. I know that at a few LE agencies still use Colt SMGs and/or MP5s, but from what I understand, that's due to very specific circumstances and for specific applications. I'm talking about the utility of using a PCC for a truck gun or HD. Thanks in advance; I'm all ears.