Group size with a 357 4 5/8" barrel need help

[jpickar]

I have two Blackhawks in 357. One is a 6.5" barrel and shoots all the holes touching if I don't screw up at 50ft off hand. With mot 38 and 357 ammo.

The other has the 4 5/8" barrel and I am doing good to get a 4" group at 50ft. off hand. I have tried all sorts of ammo and my reloads.

Any suggestions as what to look for. :? I have done the trigger work and checked the cylinder bore alignment, etc. I am baffled as to what else to look for.

Thanks, John

 

[REP1954]

Could be bore constriction at the barrel threads or a bulged barrel. Oversized cylinder throats could also be the culprit or a combination of things.

 

[threescrewheekma]

Hey jpickar,

Does the muzzle crown look OK? No obvious gouges? Same for the forcing cone? Are you shooting mostly lead, mostly jacketed or a combination?

Depending on what you shoot, barrel leading could be a possible culprit.

Best,

Threescreheekma

 

[jpickar]

Muzzle, forcing cone are fine. Barrel is free of lead. I clean out the lead with a Lewis lead remover. I use cast and jacketed bullets. I have not checked the cylinder throats yet. I will do that. Barrel isn't bulged but I'm not sure how to check for barrel constriction at the threads.

John

 

[threescrewheekma]

jpickar,

Hope this doesn't come across as crass, but if you're shooting both guns at the same distance, maybe you just don't shoot the shorter barrel as well?

Best,

TSH

 

[jpickar]

That thought has crossed my mind. No offense taken. But I shoot my 3" SP101 ans S&W 3" model 65 at 45 ft better than my 4 5/8" blackhawk. So I doubt that is it.

 

[contender]

Have you had another shooter who is a good shooter try both guns to see what happens to them?

 

[threescrewheekma]

Probably so, but another thing to keep in mind is the much shorter lock time and faster hammer fall of the double action revolvers when firing single action. Could be the longer hammer fall of the SA combined with a shorter barrel is enough to make shooting accurately more challenging.

Have you shot it from a bagged rest vs. offhand?

Best,

TSH

 

[CraigC]

How does it shoot off the bench? Bench testing is really the only way to find out what accuracy the sixgun is capable of and whether it's you or the gun.

 

[jpickar]

I agree bench testing is the only way to actually see how a gun shoots and I have not had that opportunity yet. To much ice, and rain today, on the picnic table to do that.

I guess I better just be paticent and wait for good weather and do some bench testing. I am tired of these long northern winters.

John

 

[threescrewheekma]

I know exactly what you mean about long winters. I grew up in North Iowa, about 15 minutes from the Minnesota border. Recently moved to Dallas for work--and I gotta say, a guy can get used to winters like this!

Hope the snow melts soon so you can shoot your Blackhawk.

Best,

TSH

 

[Bucks Owin]

How does it shoot off the bench? Bench testing is really the only way to find out what accuracy the sixgun is capable of and whether it's you or the gun.

You beat me to it.... :wink:

 

[Iron Mike Golf]

+1 on a bench test.

Regarding barrel constriction, you have 2 methods: slugging and gauging.

Gauging is more definite. Use pin gauges. With no restriction, one size will slip down the whole length of the bore. Next size up won't enter the muzzle. With a restriction, the gauge will go partway down.

With slugging, you do it by feel. You're checking for a restriction before you get to the muzzle. So, once you get your slug fully in the bore, push it the rest of the way with a rotating cleaning rod. If you have to push harder on a spot (or get out the hammer to tap past), you got a restriction. Likely spot is where the barrel threads into the frame.

Say, how is the cylinder timing? Is the chamber well aligned with the bore when the cylinder's locled?

 

[jpickar]

Cylinder lines up with the bore real nice.

I will try slugging the bore as I can do that. I could tell by doing that.

Thanks, John