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View Full Version : Odd Range Results: 2-inch bettering the 3-inch


ulmer
November 9, 2006, 07:24 AM
Well another of those informal reports. It's a one shot affair where I line up 10 plastic half-gallon milk cartons at ground level. Some of these tests are inconclusive as a shot must not only be aimed at the front carton, but has to be level in order to line up the cartons.

I fired the .38 2-incn Charter using FMJ 130 grain, and recovered the bullet unexpanded from the 10th carton where it had impacted the back wall of that carton. Curious thing is I did the same test with the S&W Model 60 3-inch .357 while firing the .38. The Smith's bullet stopped in carton #9. Firing a .38 out of a .357 is supposed to lose about 50 fps but it seems this would not account for the Charter's better performance. Charter does claim superior barrel rifling but I took this for hype. Mine was a very limited test but it does cause me to wonder. Anyone know what is happening here? Thanks.

Edward429451
November 9, 2006, 10:57 AM
Maybe the Charter has a tighter bore than the Smith so pressures were slight higher and resulting velocity more, or maybe the Smith has underrsized cylinder throats (they seem to be famous for it). When your cylinder throats are undersized as vs the bore size, the bullet is swaged down under pressure, then when it gets to the barrel, it's undersized and doesnt seal as well so velocities are lower. This condition also usually affects accuracy, so if I'm correct, your CA would be more accurate than the S&W. (Probably).

Slugging the barrel and having the cylinder throats reamed to .001 over bore size corrects this and usually results in better accuracy with all bullets also.

I'm no gunsmith but this is my understanding after having read up on the subject some. I'm trying to get a smith to shoot where it so far will not. I measured my cylinder throats and they are ~.355 (or less!). Maybe someone else will chime in who has more than a basic understanding of the issue.

FPrice
November 9, 2006, 04:41 PM
The 3" barrel should give you a little better performance than the 2" in general. But I am going to guess that many of the tiny variables that exist from round to round and gun to gun (and possibly even plastic milk jug to plastic milk jug) lined up in favor of the Charter Arms and against the S&W. Most likely if you were able to repeat this test a lot more times you would see diffrerent results.

It would also be interesting to chronograph the round as you were testing it for penetration, i.e., have the chrono between the gun and the milk jugs to get an actual reading on each test.

ulmer
November 10, 2006, 12:19 PM
Yes, good to see these two replies. Very likely more tests and so more data would say something here: loadings not always identical, etc. Could be this combined with the 50 fps loss would be the difference. And who knows, perhaps Charter is doing something special.

FPrice
November 10, 2006, 03:03 PM
I also have an older Charter Arms 2" Undercover and consider it one of the best buys for the money I have ever made.