[Gary Brintzenhofe]

Shooting 147 gr. rainier HP
Power pistol 5.2gr. started load through 6.9gr.
C.O.L. 1.40
firm crimp
This is what i tried . They keyhole no matter what the power range is. 124 gr. work fine .

1 maybe to much crimp

2 maybe power to fast

3 maybe less power

The crimp just seems to hold it firm. Shooting out of 3.9 in. barrel. Does anyone else use power pistol ?
Maybe someone else had this trouble ?

[RadioTech]

I'd bet that the twist won't stabilize the heavier bullet. Seems this cartridge was developed for the 125 or lighter bullet.
Just my guess.
Brian

[rcmodel]

My first thought is, you aren't getting enough velocity with 147 grain bullets to stabilize in your guns rifling twist.
I imagine they might have to be cranked up to a full-tilt boogie, and you can't with plated bullets.

Have you tried any 147 grain factory loads in your gun?

rc

[Gary Brintzenhofe]

NO it seems all i shot is my reloads. I have some other 147's that should be in soon. maybe these can't be used in the 357. Was hoping someone else tryed them.

[Jim Watson]

Sig-Sauer uses a 16" twist in .357 SIG barrels. Since S&W uses an 18.75" twist to stabilize 158 grain .38s at black powder velocity, I think we may dismiss insufficient twist or low muzzle velocity as problems.

I think it is the plated bullets, I have had mediocre results with Rainiers in other calibers, though I do not load .357 SIG. There may be some connection with alignment in the very short .357 SIG case neck.

Are the satisfactory 124s plated or jacketed?

Nothing to do if you want heavier bullets but to try other brands.

[ReloaderFred]

I've loaded thousands of rounds of 357 Sig, but they've all been with 124 and 115 grain bullets. The round was designed around the 124 grain bullet to match the ballistics of the 125 grain .357 Magnum load from a 4" barrelled revolver.

The only time I've ever had bullets tumble from either of my 357 Sig pistols was with plated 124 grain bullets and Power Pistol, but I was pushing them at over 1,400 fps, which is way over the threshold for plated bullets.

Since the round was designed for 124 grain bullets, your pistol is probably set up for that weight bullet. You also may be crimping too tight and breaking the plating, or scraping it off during bullet seating. Either of those will cause bullet tumbling.

Unless you're dead set on using 147 grain bullets, my advice would be to drop down to 124 grain bullets. That weight will work best, and probably shoot to point of aim in your pistol. If you're going to stick with the 147 grain bullets, then you might want to try Hodgdon's Longshot powder, since it's better suited for that bullet.

Hope this helps.

Fred

[ArchAngelCD]

That sounds strange, especially since the 124gr bullets work fine. Like suggested above, it's possible the bullet isn't stabilizing which is causing the problem. Maybe the twist rate of the barrel is too slow for a 147gr bullet. Just a guess on my part though.