357 magnum loads

[dakotamar]

Trying to work up some 357 magnum loads. I used 4.5Gr of 700x with a AIM 158Gr copper plated TMJ bullet. getting 242fps in stead of the expected 949fps. I am not crimping the bullet does this make a difference?

 

[stang]

Yes it makes a difference but not that much.
Are these rounds even going bang? You are under risk of getting a bullet stuck in the barrel.

 

[tactical870]

I shoot 357 with a 158 LCSWC and 4.9gr of 700x with a heavy crimp. Never had any issues although I find them dirty and will be pushing them to maybe 5.5 gr on the next loading

 

[easyrider604]

Trying to work up some 357 magnum loads. I used 4.5Gr of 700x with a AIM 158Gr copper plated TMJ bullet. getting 242fps in stead of the expected 949fps. I am not crimping the bullet does this make a difference?

Did you mean 942 fps? That's somewhat slow for that charge of 700X. Could be because Plated bullets have more friction drag than lead bullets. I am getting 1,000+ fps with 4.5-4.6 grain 700X under 158 grain LSWC in 38 spl brass out of a 6 inch GP100.

Could be because they are not crimped. A little roll crimp will help with consistent velocities and maybe a little higher average velocity.

If you want closer to full magnum speeds (1,200+ fps), try 14.0-14.5 grains 2400, but you need to use Jacketed bullets, not plated (like the AIM TMJ)

 

[Ganderite]

700x is ok for a mid power accuracy load, but not for higher velocity. It is too fast.

You want a slower pistol powder like 296, Blue Dot, H110 or N110.

All but the Blue Dot would need a good crimp for good ignition. These powders will all give 1100 to 1200 fps. I use all 4, with Blue Dot being the only that gets result similar to the book values.

 

[dakotamar]

Did you mean 942 fps? That's somewhat slow for that charge of 700X. Could be because Plated bullets have more friction drag than lead bullets. I am getting 1,000+ fps with 4.5-4.6 grain 700X under 158 grain LSWC in 38 spl brass out of a 6 inch GP100.

Could be because they are not crimped. A little roll crimp will help with consistent velocities and maybe a little higher average velocity.

If you want closer to full magnum speeds (1,200+ fps), try 14.0-14.5 grains 2400, but you need to use Jacketed bullets, not plated (like the AIM TMJ)

nope i got it right,242fps, I will have to up the powder charge and see how it goes, must need some more for the copper plating.
I have some IMR-4227 I can try but didn't find any load data for it. is it the same as H4227?