Revolver Accuracy

[Adies Gunny]

Back in the 80's I was getting into handgun hunting. I had some Contenders in various calibers and several rimfires for small game. After mounting a scope on a S&W Model 17 I noticed something about my groups. I had two distinct groups from every cylinder. There would be two rounds touching and a very tight group of four about 1" right and 1-1/2" lower. That lead to some testing.

I marked the chambers 1-6 with a grease pencil. Then I put up a target with 6 bulls eyes and fired five cylinders at them from the bench at 25 yards. The grouping surprised me. Chambers 1 and 2 were almost identical with both groups being about 1/2" and at point of aim. Chambers 5 and 6 were close being about 3/4" but right and low Chamber 3 was a 1" group and chamber 4 had another 1/2" group but it was the lowest and farthest out.

I used the #1 and #2 chambers to adjust the scope and tried to use those exclusively when hunting. I eventually switched to semi-autos for hunting because I had tighter more consistent groups from them. For a while I used a S&W 41 but it got traded so I moved to a Ruger MkII Government model that I still use occasionally today.

My go-to hunting handgun for deer and hogs is a Ruger Blackhawk .45 Colt but I do sometimes slip a S&W Model 60 in the mix. I have not done any extensive accuracy testing on either of those.

 

[Alan]

That chamber mapping you did is truly brilliant! The way those groups hold up across 5 cylinders isn’t just luck, it’s revealing something about the gun itself. It’s likely related to cylinder timing or forcing cone alignment, like someone else might have mentioned but either way, you’ve proven it wasn’t your fault. Great call on switching to semi-autos for hunting! And that .45 Colt Blackhawk is a perfect choice for hogs.