Rossi .357 Carbine question

by AaronB, Monday, December 05, 2011, 11:18 (4686 days ago)

Got a good afternoon in at the range yesterday, sighting in the Rossi Puma '92 copy in .38/.357 that I'd got for my son some months ago.

The rifle had been shooting high, to the tune of a foot high at 50 yards even with the rear sight at its lowest setting. In order to remedy this I had obtained a taller front sight. This did not fix the problem, so yesterday afternoon I went to the range with a file set and a big box of ammo and commenced to dialing it in.

The ammo I was using was a load similar to what I expect my son to use hunting deer, which was the Reminton 125-grain jacketed HPs in .357 Mag. I filed on the back sight to bring the top of the sight down, and used a needle file to keep the groove proportionate, until it was shooting perhaps three inches high at 50 yards.

This sounds worse than it is. It's predicated on a six-o'clock hold that put the center of the target one-half of the diameter of the front bead above the edge of the front bead. So if you are looking through the sights, imagine another front bead on top of the one that's there, and the point of impact is at the center of that imaginary circle. With this arrangement I could hit a target about the size of a playing card at 50 yards with perfect consistency. This isn't quite the limit of what my eyes will do with open sights, but it's not too far from it.

From elsewhere on the web I found that this load is probably delivering about 2000 fps and 1150 lb-ft of energy at the muzzle.

I don't anticipate that the carbine will ever be used to take shots longer than that at game. In fact, I sighted in at 50 yards specifically because in the conditions in which we hunt, that's a fairly typical shot.

Question: Based on these ballistics, where should I expect point of impact to be at 100 yards? We ran out of day before I could set up a 100-yard target and try it.

-AaronB