Model 10 ammo differences

[GaryED50]

Recent range trips seem to indicate It prefers 130 or 132 grain ammo to 158 grain. accuracy is far better with the lighter bullets. 125 grain +p seems to work better as well. I know its likely the guy behind the gun, but these seem to be the results

Gary

 

[shurshot]

My old early 70's model 10 is just the opposite, its loves 158 grain ammo... dead on at 25 yards. I believe S&W uses (or previously used) 158's to test fire / sight them in.

 

[T. O'Heir]

The lighter bullet will have less felt recoil. That alone will help accuracy. Not as much as a trigger job and good sights though.
A .38 Spec. 125 grain +P at 975 FPS out of a 2.25 pound revolver(a Smith 10 weighs 2.125 pounds.) has 2.9 ft-lbs. of recoil. A 158 grain LHP +P at 900 FPS out of a 2.25 lb. revolver has 4.3 ft-lbs.