Cylinder Chamber leading

[coat]

I am getting leading in my 357 cylinder chamber my load is 6.0grs unique with a 150 to 158 swc.I size them to .358 My mix is not real hard maybe less then lyman no 2. can someone here help me out. I do not get leading out of my barrel just my cylinder. As you can see its not a hot load at all THANK :castmine:

[Down South]

Your load may be too hot with the Unique. I don’t know for sure since I’m away from home and I don’t have any of my manuals with me.
If you can, you need to measure the throats and bore to make sure you have a good boolit fit. Another way to see if the boolit is too small or large for the throats is to take one of your sized boolits and see it you can push it through the throats.
A good fit is a slight thumb pressure to shove the boolit through the throat. A loose boolit in the throat will cause gas cutting and therefore lead the throats.

[462]

coat,

I agree with Down South. Boolit size should be at least .001" larger than the largest throat size.

Hornady's 2nd lists 6.0 grains of Unique at 1050 fps. Try a slower powder, too, like 2400.

[Edubya]

Are you using magnum brass? Is there any sign of lead above the cylinder, the crane? How about the gap between cylinder and barrel?
EW

[44man]

There is a small gap from the end of the brass to the throats. If the boolit is too soft and slammed with a lot of quick pressure, it will expand into that gap, then get scraped off as the boolit is again sized in the throats.
The next problem is the actual throat size. If you size .358" and the throats are .359", you have gas leaking. Alignment of the boolit in the chamber and throats is also important, if everything is too small and the round is laying in the bottom of the chamber you can have a problem.
Sizing a soft boolit to .358" and then seating it with good neck tension can reduce the boolit size as can a tight crimp that the boolit has to open and get through. Sometimes the crimp does not open and the boolit is sized again.
A whole lot of things to look at, more then I listed.
The first thing I do is to make the boolit HARDER and then even HARDER again. Try to match a jacketed bullet first. To expect soft lead to shoot like a jacketed bullet at the same velocity and pressures can lead you into a maze.
And this is just a start, I can't even remember all of it.

[Edubya]

There is a small gap from the end of the brass to the throats. If the boolit is too soft and slammed with a lot of quick pressure, it will expand into that gap, then get scraped off as the boolit is again sized in the throats.
The next problem is the actual throat size. If you size .358" and the throats are .359", you have gas leaking. Alignment of the boolit in the chamber and throats is also important, if everything is too small and the round is laying in the bottom of the chamber you can have a problem.
Sizing a soft boolit to .358" and then seating it with good neck tension can reduce the boolit size as can a tight crimp that the boolit has to open and get through. Sometimes the crimp does not open and the boolit is sized again.
A whole lot of things to look at, more then I listed.
The first thing I do is to make the boolit HARDER and then even HARDER again. Try to match a jacketed bullet first. To expect soft lead to shoot like a jacketed bullet at the same velocity and pressures can lead you into a maze.
And this is just a start, I can't even remember all of it.

44, I'm trying to figure out how these swaged wadcutters are leaving my barrel so clean. I've shot a couple of hundred of them without cleaning and they are still accurate. Admittedly, very lightly loaded, but then again, so are my .22 rimfire.
I'm not trying to start a p---sing contest, I'm just trying to understand the dynamics of the hard cast bullet not causing leading.
How about if he used already fired brass and limited the sizing length to just cover the neck?
EW

[44man]

44, I'm trying to figure out how these swaged wadcutters are leaving my barrel so clean. I've shot a couple of hundred of them without cleaning and they are still accurate. Admittedly, very lightly loaded, but then again, so are my .22 rimfire.
I'm not trying to start a p---sing contest, I'm just trying to understand the dynamics of the hard cast bullet not causing leading.
How about if he used already fired brass and limited the sizing length to just cover the neck?
EW
There are too many variables. A few grains of powder can change things. Dimensions of the gun can change things.
The hard cast CAN cause leading too.
Just never sit on one way of doing things. If it is causing a problem then you just have to move and try something else. If you have no problem, stay there! I am not against what works, only when someone keeps repeating over and over expecting things to improve.
Be like me, if a load does not shoot accurate or leads the gun DUMP IT QUICK and don't go back to it. Don't even record it in a book, just leave it. If it shoots, DON'T change anything.

[Three-Fifty-Seven]

Does it look like this?
http://i153.photobucket.com/albums/s220/ShawnTVT/Guns/BarrelCleaning003.jpg

This is after I thought I cleaned mine! I was shooting 38 specials in mine.

[coat]

123 DieselBenz Yes i looks like that. I also used Mag Brass. i think i will size .357 next time My Ruger take 358 this is smith wesson mod 27 with a 31/2 bal

[Edubya]

coat, I'll make one last suggestion and then leave you and the rest alone. Try to fit one of your freshly cast boolits, unsized, into a fired case. If it fits, you may want to try fit it back into your cylinder. If it fits, try to size the brass just enough to cover the bullet base when seated. this may be larger than your barrel, i.e., a .359 going into a .357 barrel. That means that the boolit does not have to obturate but it will fill the forcing cone, preventing 'gas blow by' and sealing completely. You may notice a little more flattening of the primer, meaning higher pressure. So, do this with the lightest recommended powder charge and work up from there.
Good Luck,
EW

[Bret4207]

123 DieselBenz Yes i looks like that. I also used Mag Brass. i think i will size .357 next time My Ruger take 358 this is smith wesson mod 27 with a 31/2 bal

That's the wrong direction! You don't want a smaller boolit, that'll just accentuate your leading. Try a larger boolit, go for .359. Fit is King with cast. You start with fit and then work your powder to suit your alloy till you hit the max for that alloy. You'll also need to watch your lube during this. But always start with boolit fit. There's a very good chance your boolits are too small now and that would explain the leading you're getting. The other option is that your alloy is just not what you think and is way soft. What are you using for alloy?

[243winxb]

Leading is normal as long as accuracy is what it should be. If you shoot the gun every week, you dont need to clean it. Bees wax/alox lubes keep it from rusting. Just wipe off the outside. For storage, then clean with Hoppies #9. Let barrel, cylinder soak so the #9 can work. A week is good, then brush and patch. As far as powder i like Alliant 2400 @13gr. with 158gr lead for the 357 mag. As for bullet diameters, .3575" to .358" works in all.

[243winxb]

When loading for revolver or auto a small ring of lead can be shaved from the bullet on seating. This ring mixed with lube and powder residue will form at the case mouth area in the chamber, it is the hardest to remove and causes auto pistol to not close the action fully. You want to avoid the lead ring. If the brass is not trimmed in a revolver to the same length or the case mouth not belled correctly, you will shave lead on seating the bullets with a roll crimp seating die. In an auto, belling must be enough to not shave lead, but the 45acp never needs its brass trimmed, so you have different lengths of brass you have to work with. To avoid the lead ring here, we bell the case mouth enough, then seat the bullet without crimping. Then in a separate operation a taper crimp is applyed.

[The Virginian]

Use Ed's Red and a well used bronze brush wrapped with some Chor-Boy copper mesh pot scrubber on your cleaning rod and make a few passes until all the lead is gone. It is cheaper than a Lewis Lead remover and the Chor-Boy is available at the grocery store.

[glicerin]

My 1960's S&W #14 was cylinder leading with .357-8, so I checked throat, was a too tight fit on .357, and bullets in Win nickel brass wouldn't chamber because of bulge. I started sizing in .356 die, actually came out .3565 and leading problem was solved(for light PPC loads).

[44man]

My 1960's S&W #14 was cylinder leading with .357-8, so I checked throat, was a too tight fit on .357, and bullets in Win nickel brass wouldn't chamber because of bulge. I started sizing in .356 die, actually came out .3565 and leading problem was solved(for light PPC loads).
Good observation. That is why a boolit is best if it just fits the throats. The best is a boolit over size for the bore a little and a good fit in the throats and it works better if the throats are then made to fit the boolit if they are too small.
I can actually shoot boolits .002" under throat size because I make them hard.
Then like you say, a tight chamber can foul things up. Does no good to make a boolit larger if they won't chamber.

[Bret4207]

My 1960's S&W #14 was cylinder leading with .357-8, so I checked throat, was a too tight fit on .357, and bullets in Win nickel brass wouldn't chamber because of bulge. I started sizing in .356 die, actually came out .3565 and leading problem was solved(for light PPC loads).

You got one of the exceptions. That's unusual. But in the end you fit the boolit to the gun and it worked for you.

No offense to 44 man, but the "harder even if it's undersize" has never worked for me. Must be you're doing something I've never done yet.

[Bret4207]

Leading is normal as long as accuracy is what it should be. If you shoot the gun every week, you dont need to clean it. Bees wax/alox lubes keep it from rusting. Just wipe off the outside. For storage, then clean with Hoppies #9. Let barrel, cylinder soak so the #9 can work. A week is good, then brush and patch. As far as powder i like Alliant 2400 @13gr. with 158gr lead for the 357 mag. As for bullet diameters, .3575" to .358" works in all.

I've got a couple 357's that would prove you wrong. They don't lead either with proper sized boolits.

[44man]

You got one of the exceptions. That's unusual. But in the end you fit the boolit to the gun and it worked for you.

No offense to 44 man, but the "harder even if it's undersize" has never worked for me. Must be you're doing something I've never done yet.
Yes, it is strange. I do that mostly in my .44. I make my boolits .432" for it but have some smaller molds that won't go over .430", also some LBT boolits left at .430". I try to keep BHN between 20 and 22 for it. Water dropped WW boolits shoot good but if I make the alloy a little tougher by adding some tin and antimony, accuracy is better. Strange thing is the BHN does not change much and it takes real effort to get to 25 or more. Might be the WW's were a little softer to start with.
I had a devil of a time getting the RCBS Keith PB hard enough when I was testing fast powders, 231 and Unique. I started with air cooled WW, then water dropped, and moved up to as hard as I could get them. A few pushed 30 BHN.
I never had any leading but accuracy at 25 yards was poor and got better as I got harder until the hardest boolits were pushing 1" at 50 yards.
This boolit is .429" one side and .430" the other. My throats are .4324" and the bore is .430".
I don't know what is going on, is BHN so important? Or is it the composition of the alloy?
I do know if I start with 20# of WW's and add 6.4 oz of tin and 9.6 oz of antimony, that is the alloy of all of my posted groups from all of my revolvers. That is what worked best with the fast powders too but I had to oven harden them to get them hard enough.
I have been working with a 50-50 mix of WW's and pure, hardened, for my 45-70 BFR and get zero leading, very small groups but have a few fliers. I have to try annealing the checks to see if the fliers go away. Then again, I use 4759 in the 45-70 with a tuft of Dacron on the powder. A slower start to the boolit. I tried Unique and 4227 and might as well throw the boolits downrange.
Strangely, Varget burned clean and was pretty accurate in the 10" barrel but velocity was low. 3031 left the bore and brass full of unburned powder. 4198 gave me wild pressure excursions with cast but shot a jacketed REAL tight. (More friction?)
I then tried a 420 gr boolit and reduced the 4759 to 27 gr---BAD move. Shots strung all up and down and every shot had a different sound and recoil. I need MORE powder behind it.
Anyway, I also pull out what is left of my hair sometimes and every question can be hard to answer. I can only suggest things.
And for Heavens sake, never pull a load out of a book or use an untested alloy and load 500 rounds! [smilie=l:

[243winxb]

Kleen Bore Stainless Steel 38/357 Caliber Chamber Brush. These brushes are sized properly to clean the cylinder chambers of a revolver. Helps remove carbon build up within the chambers for ease of loading and extraction. https://www.budsgunshop.com/catalog/product_info.php/products_id/23627 TIP: When done cleaning, rinse the brush in 91% Isopropyl Alcohol.