Agreed.
A 16- or a 14.5-(or 14.3-)inch gun (the latter with a proper length pin-and-welded muzzle device) is "typical."
According to CQB SME John "Chappy" Chapman, the 16-inch gun is still very usable, CONUS, indoors - I am definitely in no place to agree, and even my agreement is about as worthless as can be, given his standing as SME
, but yeah, I definitely do agree.
A 14.5-gun still nets 16" when all's said and done with the appropriate muzzle device, but what you'll likely notice more is the difference that makes, in terms of weight/balance of the gun. It's harder to make a 16"-gun "feel alive" than it is a 14.5. My 16" is about as light as you can make it forward of the receiver, but it's noticeably slower on the swing versus my daughter's 14.5," both are BCMs, with pretty much "equivalent" configurations (mine is a ELW BHF in a 15" KMR handguard -
https://www.thearmorylife.com/forum/threads/lets-see-your-ar-setups.258/page-2#post-3579, while hers is a fluted standard ELW inside a 13" KMR-A -
https://www.thearmorylife.com/forum/threads/saint-victor-accu-tightness.9961/); our differences in muzzle devices contribute to hers being livelier, too, but since we're focusing on length, I figured that I'd use this as point-illustration
).
If you intend to suppress, a 14.5 or just biting the bullet and doing it right by going the double-stamp route and dropping all the way to a 12.5 or even 11.5-inch gun is, in my view, almost requisite, that latter (12.5 or shorter) moreso if you intend vehicle-work. And towards the latter , again per Chappy, I would not go south of an 11.5, when looking for a serious-use gun. While similar in the way that concealment of snubbie revolvers and sub-compact pistols in that every ounce matters, that last inch taken off the 11.5 DI AR platform can potentially engender some issues which an "only one gun" or otherwise less-specific-platform-experienced shooter may not be as well-equipped to deal with.
As good brother
@Bassbob wrote, it's really "mission that drives the train." Figure out exactly what you want/need the gun for, first,
@David N., and the rest will come together almost effortlessly.