125 g plated verses lead bullets, 357 mag.

[Brianma65]

I’ve just come into a ton of 125 g powder coated .357 bullets.
I’ve never used this type of bullet before, so have a question to ask.

I’ve got data from hodgdons, and Was wondering if the powder coated bullet can be loaded a bit hotter?
If so, what the general percentage?

 

[4n2t0]

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[Brianma65]

Use lead data and work your way up.

P.S. The terms PC and plated aren't really interchange in this case.

Yes, I figured that.
I’ve read that the Powder coating allows for them to be loaded a bit hotter.

Why the big difference between the lead and the Plated?
Barrel leading?

 

[4n2t0]

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[Brianma65]

Thanks for the info.
I’ll start working up a load,
Well actually 3 loads ,as I also got a #### load of 9mm and .45 ACP as well

 

[LUTNIT]

Barrel leading is the main reason bare lead velocities are kept low. They can be pushed faster if made of a harder alloy or they have a gas check but there's still a limit.

Powder coated in non-magnum pistol calibers I work up my load exactly the same as jacketed or plated. I don't bother with lead data since I've never found a need. They tend to go a little faster with the same charge. When using HS-6 in 9mm 124gr for example I get the same velocity with PC'ed using 5.8gr and with plated bullets it's 6.0gr.

Could have issues approaching higher magnum velocities. I do know guys pushing the X-Metal coated bullets (Hi-Tek coating, not exactly the same as PC'ed but similar in my experience) to 1400fps or so in 9mm-Major guns. Don't know how they will respond at higher velocities to the cylinder gap or forcing cone in a revolver though.

 

[tjhaile]

Hodgdon appears to be keeping the lead bullet data on the conservative side if you compare pressures for the two sets of data posted. This could be because they ran into accuracy and/or lead fouling problems with higher powder charges, or perhaps they are just assuming that lead bullets would be used primarily for lighter loads.

All things equal, a lead bullet can be pushed down the bore with less resistance than a jacketed one and thus pressure will be lower for a given powder charge. You could use the jacketed bullet data to dertermine your maximum powder charge, but only testing will tell you if the powder coated bullets are still accurate at that speed.