For "minute of grapefruit" at 25 yards, my 3" vs 4" 629s have no practical difference in accuracy.

There is considerable difference in muzzle blast though, using the same 900-1000 fps 240 gr SWC loads with the same powder.

Recoil is insignificantly different in my hand. Accuracy on paper targets is virtually identical.

The anticipated muzzle blast does tend to affect my accuracy more out of the 3" though.

When using identical 44 special loads in the 3" and 4" from the bench at 25 yards, there is no significant difference in my own test.

I don't have 3" 38 cal to test with 4". Probably the 38 level loads have little difference in muzzle blast. I'd expect 357 level loads to exhibit the same kind of blast characteristics as the 44 mag experiment.

Personally I prefer the 3" barrels for belt carry.

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