Unexpected results with lead bullets

[Tech Ninja]

When I first started reloading I bought a selection of lead bullets for my SP101. I got Missouri Bullets in both 12 and 18 BHN. I loaded the 12 BHN bullets in .38 Special brass with Bullseye or Unique powder and the 18 BHN bullets in .357 Magnum brass with 2400 powder.

Everything I tried resulted in a barrel full of lead. Light charges, maximum charges, light crimps, heavy crimps, everything. And I mean so much lead that little curls of lead would come out when I ran a brass brush through the barrel. The lead was in the forcing cone and the first inch of the barrel.

I did some reading here and learned about making sure the cylinder throats were properly sized for the bullets. I tried to push a .358 bullet through each cylinder and sure enough I could not push a bullet through any cylinder.

Ah-ha I thought I have found the problem! I bought a .357 resizing die and resized some bullets These bullets could be pushed through the cylinders with a light push. The results? A barrel full of lead. Not as much lead, definitely less, but it still took 10 minutes to scrub it out.

This leading was from just five shots.

I know someone will suggest slugging the barrel but my understanding is that lead around the forcing cone is not related to barrel diameter. I could be wrong about that.

At this point I gave up on lead and went to X-treme plated bullets and lived happily ever after.

Almost.

As much as I like the plated bullets I still have 20 pounds of lead bullets. And I have to do something with them so I thought I would try one more time and see if I could make them work.

I loaded some MBC #1 Ranger 158 grain SWC 18 BHN bullets (not resized to .357) and loaded them with 18.1 grains of Alliant 300MP. That's a pretty hot load. And would you believe that made a fine shooting load without any leading! Even after 50 rounds I could run one patch through the barrel and it was clean. Really accurate too.

So why did that work? It shouldn't have worked should it? Maybe I just hit the sweet spot for that bullet.

Lead bullets have been really frustrating to me and I'm not going to buy anymore. Especially since plated are only a few dollars more.

 

[jabo52521]

Been shooting lead bullets for over 40 years. Only leading problem came from commercial cast bullets. If I get your address will send you some to try.
jabo52521 at yahoo dot com. Introduce yourself.

 

[LAGS]

I second the leading with commercial Cast Bullets.
My hand cast dont seem to lead as much, unless I really start pushing them.
But you will always get some leading from ANY lead bullet.
Gas Check bullets cut that way down in the .357
How fast are you pushing your slugs ?

 

[ArchAngelCD]

You have found out what we all find out sooner or later, if you shoot a lead bullet with too little pressure you get leading. You will get more leading from hard bullets than soft bullets. You finally pushed those 18 BHN bullet with enough pressure to seal off the barrel and stop the leading.

 

[GLOOB]

You want your bullet to start out big enough to fill the bore. And if your bore is .3575, and your cylinders are .357, you have problem. Even if you load a .358 bullet, it will only be .357 by the time it reaches the forcing cone.

You can also get a constriction in the bore where the barrel screws onto the frame. So even if you get a bullet out of the cylinder at .358, it could get squeezed down to .357 in the first part of the barrel. Then the rest of the bore might be .3575.

I'll call these things bore-continuity problems for lack of a better word. The bore gets too small somewhere, so by the time the bullet gets to the muzzle it's been sized too small by the gun, itself.

If you use deductive reasoning, you can figure out what the problem is and fix it.

You have found out what we all find out sooner or later, if you shoot a lead bullet with too little pressure you get leading.

I don't quite agree with the wording.

Higher pressure can bump up a bullet to overcome bore-continuity problems. But if there are no problems, the bullet would probably have worked fine at lower pressures.

 

[blarby]

Best part ?

You found a way to make it work.

AWESOME !

ENJOY!

 

[Steve C]

Lots of the CAS shooters will have the cylinder throats reamed to the proper size in their revolvers to "fix" the problem with lead bullets being swaged below bore size by throats that are too small. The best option if you want to shoot lead is to check throat diameter vrs bore size and resize the throats if needed. Inconsistent throat size and undersized throats was a commonly read about complaint with Ruger Vaquero's.

Reamers can be purchased from Brownells or have it done by a gunsmith.

 

[LivewireBlanco]

I also second the theory of your barrel diameter being larger than your cylinder throats. Your cylinder is probably swaging your bullets to .357 and your barrel may be slightly larger. Time to find you a fishing sinker or a pure soft lead bullet and find your bore diameter. If it's larger than your cylinder throats then there's your culprit.

 

[Master Blaster]

Try some soft swaged bullets from hornady, speer, or remington. Load them with trailboss powder to target velocity, and tumble lube the bullets first with a little lee alox. You will like it. No leading.

 

[Tilos]

All that...and lapping the cylinder throats is another way to resize them without the need to buy an expensive reamer.
The barrel restriction from the frame/barrel threads can also be lapped bigger to create a barrel the tapers bigger to smaller rather than small to big at the muzzle
The forcing cone can also be lapped/polished smooth too, all to improve cast bullet performance.

All/any of that seems to be a lot of work, considering all the coated/powder coated/ plated bullets available today, at or near the cost of cast.
I have found these "new" coated bullets are usually swaged (soft lead), don't smoke, and cost the same as cast, what's not to like
A bonus for me, because they have no lube grooves, they feed thru my $25 bullet feeder.

 

[Elkins45]

Most commercial bullets brag about being hard cast, but a too hard bullet rattling down a bore that's too big is a recipe for gas cutting and therefore leading. My guess is that this mega load is probably smacking the hard bullet with enough force to obturate in the bore even after being swaged down by the cylinder throats.

Ruger has a reputation for undersized throats--don't know if its deserved, but I hear it a lot. You might benefit from some softer bullets.