38 vs 357 odd grouping

[shugie]

I've been using the Mateba Grifone today, bought from a chap on here, and quite an interesting gun being a revolver in carbine format (as I have at the moment at least). I started off using 357 magnum as I had stock of that for my Rossi. But being a revolver nearer my face than one might normally use a handgun, I found the back blast to be a bit fierce, it was like momentary concussion, and the shooter in the next lane at Melville was not a happy bunny. There was also a large flash visible, so at the lunchtime break I pootled down to the range office and bought some 38 special for the quite reasonable sum of £30 the hundred.

That was much nicer to shoot, and no grumbles were forthcoming. It also grouped nicely at 25m, but what puzzled me was that the group was about 3" higher than with the 357, same weight bullet I think, but why was the group higher?

[dromia]

Less velocity, longer time for the bullet to travel down the barrel therefore barrel higher when bullet leaves it.

Or it could just be the faeries.

[shugie]

Less velocity, longer time for the bullet to travel down the barrel therefore barrel higher when bullet leaves it.

Or it could just be the faeries.

Nah, the faeries were in the next bay and went home at lunch time. At least I think it was the faeries, they had the steel roller door down in case we saw them and their section 7 stuff.

[Countryman]

Target load vs factory load from the range office. More powder, higher velocity higher POI

[ovenpaa]

Agreed, factory Magtech point of impact is visibly higher than our home loaded ammunition for both .38sp and .357mag.

[Sim G]

Less velocity, longer time for the bullet to travel down the barrel therefore barrel higher when bullet leaves it.

This^