Been loading and shooting cast  powder coated bullets for a while.

245gr SWC
Lyman Bullet Mold #429421

Sized to .429

Using a Smith 629-6 5 inch with a factory forcing cone that appears to be cut by a chainsaw.

I have ran many different powders and loads using this bullet, and seen no leading issues.

My standard load is 9.0grs of unique.

My new standard for full house will be 23.5grs of H110 with Winchester Primers.

I have made and shot only few cylinders of this H110 load and saw no leading.

They clock at 1329fps AVG.

I read some use gas checked bullets and some don't.

Elmer didn't.

So, with my mystery lead, that is on the soft side anyone see a leading issue in my future?

If you running powder coating and your tests show no leading so far....then try 100 rounds and see how it goes.

If you are gonna run straight lead...especially mystery lead and no powder coat?  Gas check em.

De-leading just sucks.

I couldn't agree more.

I'm not saying that your powder coated mystery lead is going to work but from my own experience I'd say it's got a chance.

Unless you are less than 12BHN hardness it has a decent chance. If you are above 12BHN hardness you have a pretty good chance.

It also seems the larger the bore the better no gas check works.

The only thing that bothers me a little about your bullets is the diameter. Why only .429" isn't jacketed bullets .429" ? I'd want at least .430"

Motor

Got back from the range today.

All was good.

The gun is a tac driver with the Unique loads and a pleasure to shoot.

The H110 loads are
impressive and a crowd pleaser, but hard to stay on target after the sixth cylinder or so.

I'm not going to change a thing.

No spitting, even though I could throw a small cat though the B/C gap, and not one speck of lead.

This is a little off topic (it's not a 44 magnum) but relevant.

I finally got to try my softer (12 to 15 BHN when cast) bullets with my hotter loads.

These bullets are 440gr Lee sized .501" and powder coated with Harbor freight red using shake and bake method.

This bullet IS designed for a gas check but I don't use one.

My normal load for this bullet cast in the hardness range mentioned above is 13gr Unique.

This past Sunday I tested these using 27.5gr Lil-Gun in Starline "R" brass using CCI-200 primers.

This is an established load and is actually the starting load in the Lyman cast bullet manual but is a lot more powerful than than the 13gr Unique load.

I'm very pleased to report that even with the softer alloy everything worked excellent.

I had absolutely no lead fouling in the bore or the muzzle brake and accuracy was excellent as usual.

Oh almost forgot: This is a 500 S&W revolver.

ETA: According to the Lyman Cast Handbook, which is using this specific Lee bullet, this load should be producing 33,200 psi. (velocity of 1450 fps)

As much as I like....... ( I edited this out after looking at the Lee manual)

There is no calculations its a simple chart. After looking it over carefully I've come to the conclusion that it's absolutely useless.

Even before I started powder coating my chamber pressure was above what it says not to exceed and the bullets worked great except for the muzzle brake being lead fouled but that's after the bullet clears the barrel.

The load I am shooting now produces at least 2x the pressure that Lee's alloy strength chart says my alloy should be able to handle. I guess this is why I never paid to much attention to this chart.

Some people say baking the powder coating softens the bullets. Cast bullets tend to age harden as well.

The bullets I am using were cast a few months ago and powder coated within a couple days of when they were cast. I'll test one for hardness and post the results.
Motor

Take the bhn down until accuracy falls off.

I've found 2 things:
When the bullets get too soft the reloading equipment/cases tend to deform the bullet itself and accuracy falls off.
9bhn alloy that's powder coated starts to fail accuracy wise @40,000+psi (308w).

With powder coating/pistol caliber gc's tend to be more of a 3rd drive band rather than a seal. I make my own gc's so I have an endless supply of them for the 44cal's. At the end of the day it didn't matter what load I tried in the 44mags, the pc coating never failed/no leading (9bhn/range scrap).