Revolver chamber size

**Bullseye54** · 06-07-2015

I have a Uberti .36 cal, revolver..
The OD of the rifling is .375..
Does anyone know what the optimal diameter of the cylinder chambers
should be?
I have a .375 HSS reamer, and .376, and a .377 carbide reamer..
Should I try to make the chambers .oo1 or .oo2 over, or try for the rifling diameter, .375??
The diameter of the chambers now are .371/.372 ..
Thank You.. Joe

**Jim_Burgess_2078V** · 06-09-2015

Joe,

Obviously if you squeeze a ball into your .372" diameter cylinder chambers and fire it into your barrel with a .375" groove diameter, you might just as well be firing a smoothbore pistol. Ideally your chambers should be .001" over your barrel groove diameter and your roundballs .001" over your chamber diameter to get any kind of accuracy. I personally favor conical bullets, especially at 50 yards, but properly sized roundballs are fine for 25 yards.

Hope to see you at Glastonbury in July.

Jim Burgess, 15th CVI

**jonk** · 06-09-2015

Undersized balls will obdurate slightly, and upset on entering the rifling. However, that is a very limited amount. They aren't minie balls after all.

If I were to offer my best advice, I'd agree with the previous poster. As with any firearm where the projectile enters from the breech, you want it to be 1-2/1000" over groove size. To achieve that, you should have chambers that are of similar dimensions, i.e. 1-2/1000 over groove size. Then go with a ball as you see fit. Assuming no chamber belling (funnel shape- some guys do this) a good lead ring being shaved off is a common good idea. I know that my gun will shave a little off of a .454, and obviously more off of a .457, and I get better accuracy with the latter; although to be fair, both will shoot better from a rest than I can hold the gun, single OR double handed.

As to the conical vs. ball debate, every gun is different. Try both! My gun will shoot both well, and basically to the same point of aim, so I choose to shoot round balls. Faster and easier to cast, load, etc.

**ian45662** · 06-09-2015

Have you tried shooting it? I have a remington with a groove Diam of .456 and chamber Diana of 451 and it shoots great. By great I mean it will stay in the 10 ring if I do my part. Now I will admit that my Hahn gun shoots better off the bench but one handed I doubt I would know the difference