Boolit sizing?

[sniper]

I just watched a YouYube video by a fellow called FortuneCookie, who says that boolit diameter should be .001-.002 over the cylinder throats. I measured my Smith's throats, and they run between.357 -.3573. He recommends boolits sized .001-.002 over the throat diameter, which seems to be the traditional advice. He says that will eliminate leading in the first 2/3 +- of the barrel.

I don't cast any more, and have been getting a small amount of leading in the first inch or so of my revolver's barrel, with my dwindling supply of commercially "hard cast" cast bullets, which measure .357. I called the caster this A.M. and he said that hasn't changed.

My cast projectiles, done with a home-brew approximation of Lyman #2 alloy , before I called time out from casting, range from .357-.359, which is in the ballpark.

Reviewing the information on various bullet manufacturers' sites, I find there are a very few that offer .358-.359 bullets, and I wonder if ordering on line from those who will supply larger boolits is worth the bother, or will solve the problem?
I guess there is one time-tested way...try it and see.:lol:

Any advice? Thanx.

[tazman]

I size mine to fit the cylinder throats to a very tight slip fit. I can push them through with my thumb, but I do have to push.
Since I make my own, I can use whatever lube I want. I use a soft lube. Either the NRA 50/50 formula or White Label alox.
I don't see how sizing the boolits .002 over the cylinder throat is going to improve your leading problem. They will just size down to throat size when they pass through. If your boolits are slightly smaller than throat size, you will almost certainly get the leading you describe.
You can try getting some boolits sized at .358 and see how they work for you.
There is a sticky at the top of this forum called "a beginner's guide to revolver accuracy". It is a good read and covers your question.

[dubber123]

Unless your bore is larger than the throats, which from my fair pile of S&W's seems unlikely, I would bet you have a frame constriction in the barrel. I have found it in many of my guns. Sizing larger than throat size will do nothing to alleviate leading in the breech end of the barrel in my opinion. Firelapping is my preferred method of correcting this issue, and I have had very good results on all that I have done this to.

[white eagle]

I size mine to fit the cylinder throats to a very tight slip fit. I can push them through with my thumb, but I do have to push.
Since I make my own, I can use whatever lube I want. I use a soft lube. Either the NRA 50/50 formula or White Label alox.
I don't see how sizing the boolits .002 over the cylinder throat is going to improve your leading problem. They will just size down to throat size when they pass through. If your boolits are slightly smaller than throat size, you will almost certainly get the leading you describe.
You can try getting some boolits sized at .358 and see how they work for you.
There is a sticky at the top of this forum called "a beginner's guide to revolver accuracy". It is a good read and covers your question.


What He said:lovebooli

[ejcrist]

I agree with the previous three too. I don't size anything more that .001 over throat diameter. If you find out it's not a barrel constriction where it screws into the frame I'd try a softer alloy. I don't know what velocities your shooting but I don't use anything harder than straight wheel weights or 16:1 in any of my wheel guns, and the fastest velocity I shoot is in a 686 at about 1,500 fps. Glenn Fryxell has written quite a bit about using softer alloys on the LA Silhouette Club website which you might want to take a look at if you haven't already. Also like tazman said, use a good lube like Alox but you probably should stay away from the hard lubes like the commercial casters use. The harder lube, and even the harder bullets, help keep things from getting deformed and messy while in shipment but don't do very well in medium velocity handgun loads.

[SteveS]

I've watched pretty much all of FortuneCookie's videos and he usually states that handgun bullets should be sized .001 over throat diameter and 'even .002 is better than undersized', which I agree with. I've had very good luck with it.

But it's not the only thing. As dubber123 mentioned, a frame constriction in the barrel will give you some leading also.

Alloy hardness can also be a factor. As is often said here, sometimes a softer alloy will solve the problem. I doubt you'll get a softer alloy from commercial manufacturers, but who knows?

There are cast bullet manufacturers who sell bullets sized to .358. Give them a try. If it doesn't work, maybe try and find some softer bullets. If no joy, maybe try fire lapping.

And depending on the level of leading you are getting, maybe just scrub out the barrel and call it good. ;)

[ReloaderFred]

Missouri Bullet Co. will size their bullets to .358" for you, and also offer their "Cowboy" bullets in 12 Bhn. I would give them a call. They're nice folks, too.

Hope this helps.

Fred