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+--- Thread: 10 mm PCC (/Thread-10-mm-PCC)
10 mm PCC - srjdsmith - 05-17-2026
There’s part of me that always thinks a rifle or carbine will always get better velocity/energy than a pistol/handgun/shorter barrel. This seems not to be true for 10 mm ammo (and others). There’s a diminishing increase above about 10”-12”, right? Is it actually diminishing out to 16”, or just no appreciable increase?
But, it seems that one can reload with slower burning powder and get better performance out of carbine/rifle length barrels. There’s also a bolt & barrel combination that delays the blow-back.
But, then, where’s the advantage? if i need pistol ammo for my G20 (clone) and different, specially loaded rifle ammo for a PCC, what have I gained? If that’s so, i may as well build a 10 mm AR pistol instead of a PCC.
Thoughts?
(Oh. I’m specifically thinking whitetail deer hunting in Iowa.)
RE: 10 mm PCC - tommag - 05-17-2026
Yep, good things to take into consideration. To maximize performance in a longer bbl you'd most likely be using a slower powder than would be ideal in the g20. My thoughts are completely uneducated as I've never had a 10mm.
RE: 10 mm PCC - olfart - 05-17-2026
Handy chart for barrel length vs velocity... link at the top of the chart to get muzzle energy chart.
http://www.ballisticsbytheinch.com/10mm.html
RE: 10 mm PCC - srjdsmith - 05-17-2026
(7 hours ago)olfart Wrote: Handy chart for barrel length vs velocity... link at the top of the chart to get muzzle energy chart.
http://www.ballisticsbytheinch.com/10mm.html
Thanks. That’s a good chart. But it confirms. There is little to no to negative advantage to a 16” barrel over a 12” barrel.
If I build a 10mm PCC it should be an AR pistol not a carbine.
Now, if the alphabet agencies would just decide what they’re doing about barrels, braces, and suppressors I could get on with planning a build.