MBC 158 LSWC in .357 mag

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RB98SS

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I've been using MBC's 158gr SWC 18 BHN in my GP100 4" for a while now but can't seem to find a load that doesn't produce quite a bit of leading. I was wondering if anyone would share a load that has worked for them in this revolver that didn't lead too bad. I'm not sure what I'm doing wrong but I've tried a number of powders and charges and I still get quite a bit of leading.

Thanks in advance.
 
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What powder are you using?
What is your goal?

I've used 5.0gr Titegroup for a very nice plinking load.
Unique and 2400 get the velocity up a bit more and leading isn't bad. In fact, I scrubbed my 6" GP100 for the first time in a long time this weekend and it wasn't very bad at all. A little bit of lead near the forcing cone, and a few strokes of the Lewis Lead Remover had it clean as new.

I've used Unique and 2400 for medium-to-heavy loads and it has retained accuracy. At 200 yards, I was hitting pretty doggone close to clay pidgeons. Leading couldn't have been too bad, or that would not have been possible.

Q
 
I haven't used that exact bullet but I've used some very similar. 8.0 grains of Herco, or 11.0 grains of AA#7. (these are pretty hot loads, you might want to back off and work up to them)
 
Are you using the 12 BHN 38 match, or the 18 BHN 357 action? I have found the 357 action to be a great bullet for my GP100 (also 4").

I do not have a load worked up for the 38 match yet (thats for next week), but I have found 12gr of AA#9 to be a good load for the 357 action. No leading, and not excessive recoil-wise, though it lets you know you are shooting a magnum.

-And now for the disclamer. Work up your own load. I am not qualified to give you load data. This works great for my gun, in my hands, with my brass.
 
I bought some of the 357 Action a few days ago. I loaded 6.0 gr. of Unique and 5.0 gr. of W231. Shot in a 6" 686. Both were smoky (lube) and leaded the barrel, which cleaned up with a couple of passes of the LLR, followed with a brass tornado brush.

I tumbled some with Rooster Jacket, but haven't been back to the range to test them.
 
I just got into loading .357. I ran through 200 rounds of the 158gr lswc over 14.2 gr of 2400. I didn't get any leading to speak of, although I did get a small amount of unburnt powder. I figure I'll have to play around with the crimp.
 
I edited my post, the bullets are the 18 BNH. I've used mostly slow burning powders, 2400, N110, H110, AA#9, Blue Dot, and I4227. Power pistol too at different velocities so I'm wondering if my barrel on my GP100 just isn't a good fit for theses bullets. That is why I asked for feedback from other GP100 users. I haven't slugged my barrel as I don't know where to get some soft lead to give it a try, but maybe that's my next option.

I also just ordered some bullets from Penn so I'll see how those work.
 
I just got into loading .357. I ran through 200 rounds of the 158gr lswc over 14.2 gr of 2400. I didn't get any leading to speak of,

Out of what?

Kludge, thanks for the link. They're out of .357 though.
 
I cast Lyman's 358477 in Lyman alloy #2. I make that by adding a pound of lead-free tin solder to 19lbs of wheelweight lead. Sized to .358" and lubed with Thompson's Blue Angel, I can shoot this up to 1400fps in my Security Six with only light leading. My standard .357 load is 12.0 grains of Blue Dot. I load this same bullet in .38 special with 8.0 grains of Blue Dot.

It casts out at about 150-151 grains in #2 alloy, and I've even loaded it in 9mm.
 
Oh, I'm shooting my loads out of a blackhawk. Are you getting leading down the length of the barrel or just near the forcing cone or the muzzle? If/when you slug the barrel, try to pay attention to whether you feel things tighten or loosen up at different points in the barrel. If your barrel's inside diameter is pretty consistent, it might just be a matter of getting your projectiles sized 1/1000 bigger or smaller.
 
Are you getting leading down the length of the barrel or just near the forcing cone or the muzzle? If/when you slug the barrel, try to pay attention to whether you feel things tighten or loosen up at different points in the barrel. If your barrel's inside diameter is pretty consistent, it might just be a matter of getting your projectiles sized 1/1000 bigger or smaller.

Down the length of the barrel. I'll plan on slugging the barrel when I get a chance. I just figured that the GP100's should have the same barrel diameter -- or at least close to one another.

Thanks to all for the help.
 
I just figured that the GP100's should have the same barrel diameter -- or at least close to one another.

Yeah, you would think. If it's all the way down the length of the barrel, it's probably not because of a tight spot, I wouldn't think. What sort of loads are you running? Mild or pretty hot? And with what powders? The action series bullets are pretty hard and you have to hit them with a good amount of pressure to be sure that they obturate (is that the right word?) so that you get a good seal to prevent the hot gases from going up the sides of the projectile.

Without slugging the barrel and taking a reading with a micrometer, it's hard to tell what is up. If you really aren't equipped to slug the barrel, you could still try a couple of things. First, I know that the Ruger GP revolvers are very nice and Ruger is a good manufacturer of revolvers. Even if you slug the barrel, it MAY not tell you what you need to know.

Now, I'm going to go assuming. Assuming that you do have a "standard" diameter barrel and .358 is what you should be using, you could try a couple of things. Order some of the softer bullets from MBC and see what they do using the loads that you've been using. I haven't had any leading problems at all, but I don't load anything mild. I load all of my stuff on the hotter side.

The other thing that you could do is order a couple of sample packs in 1/1000 larger and 1/1000 smaller and see if either of those do it for you.

As a side note, I don't think that getting a bullet to obturate is a matter of velocity, but rather a matter of pressure. What I usually do to make sure that I have adequate pressure to avoid leading is to figure the velocity that I want to obtain and then use the fastest powder that I can accomplish it with without having to run maximum loads all of the time. Everything usually runs more smoothly and cleaner when you run powders in their upper pressure ranges.

Good luck.
 
Tony,

I posted the powders I've tried earlier in this thread. The loads I've tried are all mid to upper end with these powders. I currently have some near top end Bullseye loads that I haven't fired yet (trying a faster powder). The bullets are indeed .358. Like I said, I have some Penn bullets ordered and I'll give them a go and see if they like my gun better.

My objective is to shoot magnum loads.

Thanks for the feedback.
 
You could very likely have undersized cylinder throats. Ruger is notorius for this in the Single Action line of revolvers, perhaps you are experiencing this. I dont see why they couldnt mess it up on a double action revolver also.
 
ljnowell has a point. That was the first thing I checked when I got my blackhawk. If your cylinder throats are too small, you bullet may be .358 going in, but not that size coming out. That easy enough to check though. See if one of your projectiles will pass through the cylinder throats.
 
I can tell you with a 6-7gr charge of Unique that they leaded like HELL. Not the bullets fault, just not the best load. I now shoot my standard load of 5.0gr Titegroup, medium crimp, Winchester primer. Excellent load.
 
I user MBC .357 Action bullets using 6.2 grains of Unique. Very slight leading after 100 rounds minimum. This load is the most accurate load for this gun I have had.
Definitely check your cylinder throats and slug your barrel. Is the timing on your gun ok?
 
Maybe I'll back the charge off a bit, I was at 6.5 or so IIRC. The gun is in good working order though. Also, I usually tumble-lube all lead bullets, and I didn't with that load. I can't remember what the throats measured, I thought I wrote it down somewhere...
 
Definitely check your cylinder throats and slug your barrel. Is the timing on your gun ok?

I don't think there's any issue with the timing although i'm not really sure how to determine that. It's only a couple years old and I've never have any other issues using it. It's accurate, but not after it leads up.
 
You could very likely have undersized cylinder throats. Ruger is notorius for this in the Single Action line of revolvers, perhaps you are experiencing this. I dont see why they couldnt mess it up on a double action revolver also.

I finally got around to taking another look at my GP100. I didn't slug the barrel as of yet but I did attempt to see how tight the bullet is in the cylinder throat. I was not able to push the bullet through by just forcing it by hand, no way. I did tap it through using a brass punch and a hammer. It was tight. I'm not sure how tight the bullet should be in the throat and was wondering if anyone thinks this is too tight. How easy/hard should it be to move a bullet through the throat of the cylinder?

Thanks.
 
That is too tight. You should be able to push them through by hand, with some resistance. They should not fall through. i use a plastic ink pen to push them through when I check one.
 
That is too tight. You should be able to push them through by hand, with some resistance. They should not fall through. i use a plastic ink pen to push them through when I check one.

ljnowell,

What are my options? Get the cylinder throats bored larger? Would a good gunsmith be able to do that? It just seems too extreme a thing to have to do with a newer revolver.
 
I'm thinking that Ruger should help you out with that. If not, a gunsmith can cure that. Just make sure that you go to someone reputable.
 
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