HK STATES that BOTH the MARK23 and MK23 Mod-0 have an SAAMI Spec chamber, and that the only difference is that the MK23 Mod-0 has a feed ramp that is specifically designed for reliable feeding, with the 1911 Ball .45 FMJ ammo, and the +P 185 grain JHP rounds.
The speculation of the tighter chamber, was made by a third party machine shop mechanic, that apparently did several measurements on several barrels, and came up with a .002 inch tighter chamber on the military barrel.
I cant say if this would make much noticeable difference, if only making feeding less reliable with NON military spec. ammo.
I suppose they have no reasoning to make it compatible with anything BUT military ammo.
If they can make the gun more functional with military ammo, at the expence of being a little more proprietary, then they'll do it. I guess the tighter chamber would make less room for the case to expand, and less inconsistancies.
Kind of like high-end-rifle owners fire forming the brass for extreme consistancy, except in this case your tailoring the chamber to the ammo.
A forum dedicated to and laser-focused on Heckler & Koch firearms, Heckler & Koch accessories and the owners and enthusiasts that love them! Come join the discussion regarding HK pistols, long arms, NFA arms, HK accessories, HK history and trivia and more.