Slugging new 357 revolver

[Taylor810]

I will be slugging my new 357 revolver over the weekend. Can anyone suggest the appropriate size of lead to use?

[james nicholson]

I make my own by using a drill bit larger than the bore. I drill a hole near the end of a piece of 1x2 and melt stick on wheel weights in my ladle and pour it into the hole. Saw the 1x2 near the slug then split it with a chisel. Remember to lube your slug well and use a brass rod. Lowes has brass rod in various sizes. You would use a bit that measures about .375. I drill in 2 steps, first hole with a bit slightly smaller than the bore about 1&3/8 inch deep then enlarge the hole with the larger bit, stopping at the 1" mark. That allows you to start easier.

[sghart3578]

If it is a brand new gun, or a gun of recent manufacture, I think you are wasting your time slugging the bore. I don't mean to rain or your parade.

Most new guns are boringly uniform in their dimensions. Also, if it is a Smith and Wesson you won't be able to measure the slug without pin gauges or sending it to a machinist.

Call Dardas Bullets and tell Matt your worries. I'm sure he will sell you an assortment pack of .357, .358 and .359 diameter bullets. Then load them up and test them.

I paid over $700 for my new S&W 586 and that is what I did. I didn't want to risk damaging the crown.

My 80 year old 7X57 or 30-06? No problem, I slug away. But I truly believe you don't need to with a new revolver.

Just my 2 cents.

[Mk42gunner]

A .375 Round Ball meant for .36 caliber cap & ball revolvers has always worked for me, when slugging .38/.357's.

Robert

[mdi]

Even if I wasn't gonna shoot lead bullets, I'd like to know more about my gun (I believe every manufacturer has tolerances and I want to know exactly what my particular gun measures). One trick used is fill a fired case with soft lead and when cool, use an impact bullet puller to remove the perfect size slug from the case. For revolvers a measurement of the cylinder throats is a good idea also (I size my bullets to match the throats on all my revolvers). Search here or google "how to measure barrel slugs" or something like that for hints on how to measure odd number grooved barrel slugs (as a lifelong machinist/mechanic, I can get accurate measurements on an odd grooved slug with only a 1" micrometer, I can "spin" the slug and "feel" the proper amount of pressure for accurate measurements). When I slug a barrel, I like to see a lead "donut" from a slug at least .010" larger than the bore.

[tazman]

What MDI said works like a charm for me. I have used that technique several times.

[Taylor810]

Thanks for all of the suggestions!

[cbrick]

Only one reason to slug a revolver bore and that's to know that it's at or barely smaller than throat diameter. Proper sizing for a revolver is sized to the throats. Will do no good to size to the bore groove diameter if it's larger than the throats because the bullets will be throat diameter when they exit the throats.

Rick

[williamwaco]

I use pure lead and the largest mold I have and cast about 50 bullets.

Around half of them will mike .361 to .362.

[DougGuy]

OP when you slug a bore or cylinder, you want to make sure and use dead soft lead because alloys have a bit of "springback" that will actually make the slug larger than the hole it just came out of. Not much but enough to know that it can skew your data. I get the egg sinkers at walmart and if they are not quite big enough you can sit one on a vise or other solid metal surface and smack it with a hammer, it will expand the middle of it.

As mentioned earlier, the actual micrometer/mathematical measurement of the slug's diameter is not that important. What is, is when you knock it through the barrel, when it comes out try and fit it into the cylinder throats from the front. Only if it will not go into the cylinder throats, is there a problem. Once the slug comes through the barrel, and it slides into the cylinder throats, it means the throats are at least larger than the bore which is as it should be.

The other thing to watch out for is when you are pushing the slug down the bore and it gets to where the barrel threads into the frame, if it gets tighter going through that area, it means you might have what is called a "thread choke" where torquing the barrel into the frame distorts it and causes it to squeeze down smaller in diameter. Normally this isn't an issue with .357" because the barrel is generally thicker than say a .44 or .45 caliber barrel. But you still need to know if the slug gets harder to push through this area or not.

[MtGun44]

You will find that .357 Mag revolvers have MUCH smaller variation than
the .44s and especially the .45 Colts. My bet is that .358 diam
will be perfect.

Bill

[captaint]

Taylor - If you find you have .358 diameter throats, you can be happy. That's just the ticket.

[Moonie]

I would take a piece of 38 brass with old primer in it and fill it with lead then pound it out with a kinetic puller. This is normally what I do to get a slug for straight walled cartridges.

[Char-Gar]

It is a waste of time to slug the bore of your revolver for it will be .357 +- .0003 in the grooves and I don't even know the make of your sixgun. If you want to measure your charge hole throats go ahead, but at the end of the day you will use either .357 or .358 cast bullets and you probably can't make change for a dime on the accuracy difference.

This stuff really isn't as arcane, mysterious or esoteric as many would make it seem.

[Down South]

Some great replies here. I use a 9mm mould or larger and make several pure casts. You can squish the smaller diameter boolits in a vice if they need to be a larger diameter. one thing that I didn't see mentioned. Remove the cylinder before slugging the barrel or throats. Place the cylinder chamber down on a board and slug from the throat.

[Taylor810]

Great small weekend project! Thanks for all of the comments/suggestions.

[Down South]

I realize that you probably don't have access to a set of these but pin gauges are great for checking cylinder bores. I have a set that I bought just for tasks like this. They are also useful for checking bore restritions such as where the barrel is screwed into the frame.
I discovered that my Ruger GP-100 had such a restriction. Fire lapping cured that problem.

[sghart3578]

It is a waste of time to slug the bore of your revolver for it will be .357 +- .0003 in the grooves and I don't even know the make of your sixgun. If you want to measure your charge hole throats go ahead, but at the end of the day you will use either .357 or .358 cast bullets and you probably can't make change for a dime on the accuracy difference.

This stuff really isn't as arcane, mysterious or esoteric as many would make it seem.

This.

[williamwaco]

You will find that .357 Mag revolvers have MUCH smaller variation than
the .44s and especially the .45 Colts. My bet is that .358 diam
will be perfect.

Bill

+1


By 1980, I had already lost track of how many .357s I had owned.

I have owned a few more since then.

I have never seen one that didn't work very well with .358 bullets.

[dragon813gt]

It is a waste of time to slug the bore of your revolver for it will be .357 +- .0003 in the grooves and I don't even know the make of your sixgun. If you want to measure your charge hole throats go ahead, but at the end of the day you will use either .357 or .358 cast bullets and you probably can't make change for a dime on the accuracy difference.

This stuff really isn't as arcane, mysterious or esoteric as many would make it seem.

+1
I use .359 in all of mine but that's simply to make it easy to use the same ammo in a Marlin 1894C. Maybe it's just me, but I try a few different sizes and see what works best. Sizing dies are cheap and there is zero risk of me damaging a firearm doing it this way.