Does cylinder loading affect accuracy of revolvers?

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Buck13

Buck13

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When inspecting a "loose" lockup revolver, we're told to look down the barrel and see if the barrel and cylinder seem to be concentric. You can rotate it a bit with your hand so they're not, but a little motion is supposed to be OK as long as it "wants" to be centered when you are not grabbing it. But when the gun is half-loaded, gravity is doing some grabbing.

Does this have any practical effect? The cylinder is only perfectly balanced laterally on the first and last shot. For a 6-shot revolver, as you fire the 3rd and 4th shots, there is quite a bit more weight on one side of the cylinder than the other (twice the weight of the bullet + powder charge), so there is some torque on it. With >200 grain bullets, that's a full ounce or more of lead and powder. It seems like this might cause the bullets in the middle of the string to meet the forcing cone differently than the first and last.

Has anyone ever heard of testing of this? Say, load one round only and shoot a group from a Ransom Rest, then load 4 and shoot a group by repeatedly reloading the same chamber? I'm a little nervous about loading some live rounds and pointing the gun at my face to see if I can detect any mis-aligment of the cylinder visually. :D
 
Not sure if this is what you are asking, but, I have heard of shooting groups by loading all six, then firing each chamber on separate target to determine if all cylinders group as well as the gun as a whole.
 
Some high end revolver makers/mechanics will number the chambers in the cylinder so you can keep track to determine the most accurate of them.
 
They say that very often one chamber is more accurate than the others/the rest. I've never tested for this myself.. every revolver I've ever shot has been more than satisfactorily accurate.
Also, the way I check for cylinder lockup is to cock the gun, lower or drop the hammer and with the trigger still being held back, check lockup.
 
In my revolvers, I have found some cylinders are better than others. Try it. Shoot a 36 shots with all cylinders and then shoot 36 from one cylinder. Probably the one cylinder is more accurate.
 
Seems like I haven't posed my question clearly. By definition, a "loose" lockup revolver can have the cylinder rotated slightly when in firing condition (trigger back, hammer down), right? So, if it centers perfectly when empty, but can be rotated a little, when the weight of the partially loaded cylinder creates a torque which tries to rotate it, will that be noticable?

Say you mark chamber #1, and fire a round with only chamber #1 loaded, or all chambers loaded. The cylinder is balanced, and since it centers when empty, it should be centered on firing. But if you load chambers 1, 2 and 3 only (or already fired half the rounds) and fire chamber #1, could the weight of rounds 2 and 3 rotate the cylinder slightly, causing the bullet to enter the forcing cone differently than when chamber #1 is fired with all chambers loaded equally, or none?
 
Now that I try to quantify it, the torque would be only about a tenth of an inch-pound, even in a .45 Colt. Not very much! It would have to be a pretty loose gun...
 
I remember the American Rifleman doing an article on revolvers many years ago.
The author stated his case using all kinds of measurements regarding all the additive slop of a particular revolver.. saying that this particular revolver "should" get "X" accuracy (pretty horrible).
However, when shot, (as will just about any old revolver) pretty astounding accuracy resulted.
It was an interesting article anyway.. I guess the gist of it is that the slugs get funneled just fine down the barrel.
 
shafter,

the other five cylinders will be full of 100 grain empty cases.

buck13,

most revolvers don't "lock up tight". the forcing cone allows for a little bit of cylinder movement.

if the cylinder moves too much, lead splattering back on you will let you know real quick!

murf
 
No.
Who shoots 1 chamber with the other 5 empty anyway??
Anyone who wants to fire their last shot.
Click to expand...
I was reading five holes empty.

Like only one loaded round in a six shot cylinder.

Not one loaded round and five empties.

Regardless of all that foolishness, it makes no difference anyway.

As somebody else noted, the fired chambers are not empty.
They still have empty brass in them.
So you are only dealing with bullet & powder weight.

Not empty holes in the cylinder full of sail boat fuel.

rc
 
It's the two-holes-empty state that I'm interested in, or three-empty. In a big caliber, the torque of the two unbalanced rounds (bullet + powder >= 250 grains per round) as you are ready to fire shots 3 and 4 (out of 6) would be around a 1/20th of an inch-pound, if I'm figuring it right. I don't have a good feel for how much torque that is relative to how much it took to rotate a loose (aka clapped-out) Bulldog I passed up in a shop a couple of months ago. My fingers have never been successfully calibrated in inch-pounds (or Newton-meters).
 
the gun weighs 17,500 grains. 500 grains is 2.8% of that. the extra 500 grains of weight is carried .5" off the centerline of the gun. not much of a torque arm there.

would think you would get more torque from an over rotated grip on the gun. good way to compensate for that extra bullet or two on one side.

or you could go gangsta and eliminate the problem altogether!

all kidding aside: i think this is a non-issue.

murf
 
This is why a properly designed forcing cone is important. Unless a revolver was built with line bored chambers indexed off of the barrel and with a very carefully fitted locking bolt there will be errors that the forcing cone will correct. Timing is everything in a revolver. And most are "off" a little.
 
Ransom rest / cylinder test

We ran test years ago using a ransom rest and three different revolvers trying to figure out if a custom made target pistol was that much better than a factory made gun. We ran the test on multiple occasions and the results were always identical. What we concluded/discovered was that each chamber in the cylinder had it’s own point of impact time and time again. In other words, it was never going to get any better. Ergo, the reason for numbering chambers. If you know that chamber #3 is going to widen your group and you are shooting a ten shot string loading 5 and 5, don’t load the #3 chamber.

Also, that makes the argument for the autoloader being inherently more accurate with its single chamber attached to the barrel, versus the revolver’s cylinder rotating six different chambers to the barrel.

As an aside, the three revolvers used were:

1.) 1955 target in .45acp – 4 shots in one loose hole, 5th shot slightly out and the 6th shot would open the group considerably.
2.) Registered Mag in .357 w/ 8.375” barrel – one hole group but very loose with an occasional leaker from the same chamber.
3.) Custom, .38 spl. – With, new, air gauged bull barrel; cylinder stops were welded over and precisely re-cut to the chambers & matched to the bolt. ¼” of bug; one very tight hole.

As a further aside: were you to open the cylinders and give them a twirl, the ’55 target would spin for about 2 seconds, the Reg.Mag would do about 45 seconds, and the Custom would do close to a minute. Something to think about; not very scientific; but some indication of quality, I think. How long does your favorite cylinder spend for? And, remember, it’s not how grand your piano, it how well you can play it!!!

kerf
 
too bad you can't tune a revolver like a piano when a key (chamber) is off. recutting the cylinder stops sounds like a lot of work.

murf
 
Buck13 said:
When inspecting a "loose" lockup revolver, we're told to look down the barrel and see if the barrel and cylinder seem to be concentric. You can rotate it a bit with your hand so they're not, but a little motion is supposed to be OK as long as it "wants" to be centered when you are not grabbing it. But when the gun is half-loaded, gravity is doing some grabbing.

Does this have any practical effect? The cylinder is only perfectly balanced laterally on the first and last shot. For a 6-shot revolver, as you fire the 3rd and 4th shots, there is quite a bit more weight on one side of the cylinder than the other (twice the weight of the bullet + powder charge), so there is some torque on it. With >200 grain bullets, that's a full ounce or more of lead and powder. It seems like this might cause the bullets in the middle of the string to meet the forcing cone differently than the first and last.

Has anyone ever heard of testing of this? Say, load one round only and shoot a group from a Ransom Rest, then load 4 and shoot a group by repeatedly reloading the same chamber? I'm a little nervous about loading some live rounds and pointing the gun at my face to see if I can detect any mis-aligment of the cylinder visually. :D
Click to expand...
This is a non issue. I don't understand your application of the word "torque" as it applies to a closed cylinder with fired and unfired ammuntion.

I'm carrying a S&W M327 TRR8, just for fun I opened the cylinder and dumped the ammunition. With an open cylinder, and being very careful not to bump the cylinder while reloading, I was able to load five rounds, leaving three empty, without the cylinder rotating. However, if I bumped the cylinder, the loaded rounds would rotate the cylinder so that the ammunition was at the bottom.

With ammunition at the 9:00 position on an open cylinder, it possessed potential energy until it rotated. Actually, your body will exhibit more kinetic energy by turning your head and coughing than cylinder movement with the bolt engaged. :)
 
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