I can only guess at the rifling twist on my M&P9 but it appears to be less than my 9mm Government Model just watching a dot on the cleaning rod as I run it with a tight patch into the barrels. The M&P is RH twist, the M1911 is LH.

If the one really is 1:16 and the other 1:10 it doesn't seem to make any difference shooting my normal 124gr M882 Ball 9mm ammo from either.

-- Chuck