Berry’s 158 Grain FP Load Question

[rfwobbly]

Max load of 4.3 grains for the XTP load?

Yes, if you're going to shoot the cartridge in a 38Spcl revolver. Max pressure 17,000psi.
No, if you're going to shoot the cartridge in a 357Mag revolver. Max pressure 35,000psi.

See SAAMI pressure specs

 

[lordpaxman]

Max load of 4.3 grains for the XTP load?

Yes, 4.3 gr is where I stopped in my load development for this particular combination because it met my criteria for a target load. Chrono numbers had it running less than what Hodgdon had for the XTP, but remember they are two different bullet technologies. Had I wanted to use this for Icore I would have had to exceed the published load data. As @rfwobbly points out, shooting .38 special or +P in a .357 gives you a measure of safety. Good luck and let us know the results?

 

[buck460XVR]

• The entire focus of your load data research is chamber pressure. Everything we do in reloading is to control chamber pressure.
• The gun you use also makes a big difference. The max allowable chamber pressure is different for 38Spcl, 38Spcl+P, and 357Mag.
• S&W 686 is built for 357Mag loads, so your maximum load is actually much higher than your data indicates.

Hope this helps.

Yes, if you're going to shoot the cartridge in a 38Spcl revolver. Max pressure 17,000psi.
No, if you're going to shoot the cartridge in a 357Mag revolver. Max pressure 35,000psi.

See SAAMI pressure specs

....all that said, I still always recommend to load for the cartridge and not the gun when it comes to cartridges like specials/magnums. Really no practical reason to load .38 special brass to .357 magnum pressure, even tho your platform will handle it. The minute you load a magnum load in a special cartridge, you have circumvented the safety of the longer magnum brass to not be loaded in Special platforms. While I don't think this is what you are suggesting, it could be interpreted that way.

Plated bullets have the same slick copper surface as any jacketed bullet, they're just a bit softer.

But, like jacketed, they are not as slick as lead, kinda why the OP notes that lead powder charges are less than for jacketed. Friction. Just as SWC bullets have less bearing surface than bullets with a FP profile. Again, Friction. Jacketed bullets take more "oomph" to get them started, lead bullets generally seal in the bore better and thus are more efficient. Lots of small details that go into why there are differences in powder charges with different types of bullets, in order to get the same velocities. While the core of plated bullets are "softer" than hard cast lead bullets, they are the same as swagged lead bullets, because that is what their core is....a swagged bullet.

 

[PO2Hammer]

Lead has more friction than copper, look it up.

 

[anothernewb]

HP39/W231 yes.