New guy question about sizing for a revolver

[huntingnt]

Just a quick question about sizing boolits for a revolver. I have two guns where all the cylinders measure .356 -.358 with calipers ( I don't have an inside mic). If I size to .359 will I be squeezing the slugs too tight in some cylinders for good accuracy. I am shooting a Colt Officers in .38 and a Ruger security six in .357. The Colt i'm shooting for bullseye and need really good accuracy at the 50 yard line.

[williamwaco]

Measuring revolver throats with those calipers will be off by at least .001 to .002 ( under ) disregarding the inherent accuracy of the caliper itself. This is because they are square and do not expand to contact the cylinder wall.

For the time being, forget the throats. If you have a .358 die, try it, if not try the .359.

There is at least a 95% chance that one or the other of these diameters will work just fine.

If you have no sizing die, Try them lubed as-cast. ( Expect some of them to be too large to chamber if you load them unsized.) DO NOT FORCE them. If they will not chamber pull the bullets and set those cases aside for use when you do have a sizing die.


The old Scott says

"Don't spend money to solve a problem until you have one."


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[Bambeno]

If you have an outside mic you could do impact slugs or cast's of your revolver's chambers and throats. Are you currently having accuaracy issues with you current loads? Also of alot of importance what do your barrels bores slug out at?

[MtGun44]

Sorry, with calipers the instrument itself is limited to +/-.001, and measuring throats
is unlikely to be consistent, so you are double unlikely to have any useful numbers.

Either just shoot a few that are .358 and see how they do (this has a HIGH probablity of
working well) or get a way to do more accurate measuring. You really need to know for
sure to tighter than .001 before you make any judgements.

Just try .358 if that doesn't do well go bigger, like William said.

Bill

[Larry Gibson]

.359 will be fine for both revolvers.

Larry Gibson

[Shiloh]

Size for chamber specs. My sizer die sizes at .3584

Shiloh

[runfiverun]

if the inside of a fired case from the gun measures bigger than 359 you will have no problems firing a 358 sized boolit in that gun.
don't get carried away with the ginormous boolit thing.
358 has worked in every 38-357 i have ever tried it in.
your colt might even like 356 or 357 some of thier target guns had bbls in the 355 size.