Load for FMJ rather than lead....

[robpark]

Hi all,

In my .357 Marlin Cowboy, my usual load is 3.8gr of Bullseye with 158gr lead RNFP, but I've got some FMJ/copper wash 158gr TC bullets I'd like to use up. Iirc, I should increase the powder load for FMJ, but by how much?

Cheers.

[markyw]

Should give a load in your manual for the type of bullet and also the powder you are using. The Alliant website doesn't seem to list anything other than 158gr law and 110gr Speer uchp for .357 mag.

I'll look up mine when I get home....if I remember

Good luck.

Mark

[xmarksmanx]

Try 5grains or 8.5grains of blue dot

[tacfoley]

Hi all,

In my .357 Marlin Cowboy, my usual load is 3.8gr of Bullseye with 158gr lead RNFP, but I've got some FMJ/copper wash 158gr TC bullets I'd like to use up. Iirc, I should increase the powder load for FMJ, but by how much?

Cheers.

All of my reloading manuals make a clear distinction between loads for FMJ/SJ/SP and lead bullets.

tac

[Rollo]

It also depends on the coating/jacket. Berry bullets used to say use lead load data for their copper plated bullets, but now I think they say you can use FMJ data.

[Treebone]

You need to establish whether you have true FMJ bullets or just copper plated before you up your load, there is a big difference.

TB.

[Mike95]

All the copper washed bullets in 158gn I have used, are just copper washed, not FMJ. Not much increase needed from lead load. Most of them are sized .357 and not .358. Seem to shoot well in Marlins, not so well in the Rossi. I am not sure if the PPU factory ammo is FMJ or just copper washed.

Also, nothing to stop you dipping the copper washed in a little Alox. I was also advised to clean out the lead before shooting copper washed.

Mike95

[robpark]

Thanks for the help, I finally got to try these out
I checked, and the bullets are true FMJ. I had reasonable results with 5 grains of Bullseye - then hit a sweet spot with 5.7 gr. and cloverleafed 5 rounds at 25yds
....was grouping about 1.5" lower than RNFP with 3.8gr.