Never too old to learn

Rex

Active Member
I have a barrel leading S&W 686 that I have complained about for years. I size the bullets to drop in the chambers and will almost fall through but not quite. A gentle push with a pencil gets them through. I've always thought that was right. Out of frustration I started sizing larger. My Chinese mic says .3585 instead of .357 and they don't fall through with a gentle push! I know the throat is the final sizing die but my leading is almost all gone. I know this isn't right but it works and I ain't changing! Did my barrel finally wear in after thousands of rounds of cast bullets?
I have no idea but the .357 will still lead. Yes I cleaned the chambers good before measuring the bullets.
RBHARTER sent me one of his 358477 moulds that I'm going to try it this afternoon and see what happens. Who knows, maybe the cast bullet fairy is finely on my side.
 

Ian

Notorious member
Sometimes a half thousandth makes all the difference. Think of the bullet in the cylinder throat as a piston in an engine block: It needs to seal fairly well. If gas rushes by, it will etch the bullet and spray lead dust down the bore where it gets ironed on by the passage of the bullet.
 

Bret4207

At the casting bench in the sky. RIP Bret.
Bingo! That extra 1.5 thousandths changed the dynamic fit for the better.
 

Brad

Benevolent Overlord and site owner
Staff member
This is why it is nice to be able to make my own sizers. I can start at .357 and see what happens. If I get leading I can either open that one up a little or make another at .358. Over time I end up with maybe 5 sizers for 357 revolvers or rifles.
I am fortunate to get by with just a .358 sizer for all 357revolvers in my home.

Different alloys make a difference as well. As Sb content goes up so does after sizing diameter. Easy to get .0005 to .001 difference in diameter based on alloy even when same sizer is used.
 

Rex

Active Member
Brad, that's what worries me a bit. My lead is mostly mystery metal, if it melts I pour.
 

Brad

Benevolent Overlord and site owner
Staff member
Not a problem really.I mostly use ranges crap and it can vary a bit as well. Just make large batches so you get some consistency across the batch.

Good news is I haven’t found much variation in sizing diameter until you alter the Sb content a fair bit, at lest 1%. Chances of random lead giving one batch equal to stickon wheel weights and the next like Lyman #2 is pretty small. You would also notice the difference quickly on handling.

Don't ever forget this tagline, it only matters when it does. Until the gun tells you here is a problem don’t go looking for one.
 
Last edited:

waco

Springfield, Oregon
I found that my Marlin Cowboy prefers a .361” bullet for best accuracy. What a difference a thou or two makes.
 

Rex

Active Member
I ran some 150 grain 358477 bullets out of RBHARTER's mould sized .3585 lubed with carnauba red over 6 grains Unique in .357 cases this morning. I think I've finally found what I've been looking for! The Chrony won't come out until the weather gets warm but I'd guess around 1000+FPS. It's a dandy.:):)