Looking at buying a new(Storm lake) barrel for my M&P compact.
Standard length barrel is 3.58" in length. I could put in a 4.28'" length or 4.28" ported.
It would seem to me that the longer barrel would increase bullet velocity but the ported barrel would allow the expanding gas to escape early and have little gain in velocity. Wouldn't I gain more velocity using the non-ported barrel of the same length (4.28")?
Also, is there a way to determine the velocity gain when switching to the standard (non-ported) 4.28" barrel?
I am using the 3.58" length in 357sig.
Thanks for any help!