.38spl help PLEASE!

Guys (and guyesses!)
This is my first post post so please be gentle with me! Some help from the guys in the know please.
I am using a 357 Marlin 1894 CS L/A with micro rifling (no choice here!) for target shooting ie paper punching. I am using 158grn fprn heads - very successfully with 5grns of Unique.
I have acquired 2 lbs of Bullseye and ask if anyone could give me a guide as to tried and tested loads using 38spl cases with 158 fprn heads with this powder and rifle combination.
Thanks for any help - not too plentiful here in England!
John Garnett
Cornwall
UK

2.7 standard bullseye, bullseye, [yes, the powder and the discipline for which the powder was named] target load.
to 3.6. your marlin will take 3.8 which is a +p load.

What five said. Be aware that a little goes a long way and you need to measure carefully! With typical rifle powders and amounts half a grain doesn't mean a lot. With Bullseye half a grain too much could blow up your gun.

I have worked up to 4.5 grns Bullseye 158 grn LSWCs in .38 Spl cases in my .357 Magnum M-66 4in and it is shooting one ragged hole at 25 if I pay attention. No pressure signs, no backed out or flattened primers, no extraction stickyness, coming up on 6 reloadings on the brass so far, no split necks!

I use a RD mold that is designed for the MicroGoove rifling I have the TLC 359-190RF and shoot it in my Lever Gun in the 357 Cartrdige, mostly I use 2400. But there are bullseye loads for this combination, starting at 4.1 Bullseye for this bullet in the 357 case.

Other data indicates a starting load of 2.5 grains bullseye starting and maxing out at 3.0 grains will work for this bullet in the 38 Spl cartridge.

As to the 158 grain bullet for your rifle, start with 3.6 grains of bullseye and your max will be around 4.2 grains.

I prefer heavier bullets in my 357 rifles, not heavier loads.

Hope this helps,

Jerry