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 .22 WMR
goodrat  [Team Member]
3/23/2012 3:37:54 PM
Does anyone know what the muzzle velocity differences between a 16" barreled .22WMR and a 22" inch is?
bscman  [Member]
3/24/2012 12:19:39 PM
Off the top of my head, no...

But I can tell you with a standard 40gr WMR load, you hit peak velocity around 19.5" of barrel length.
Some of the hyper velocity will pick up a bit more for another ~2inches.

I would suspect the velocity difference would be less than 100fps with most standard 22WMR loads given those barrel lengths.
Noise, will likely be quite a bit higher in the 16" however.