Tried some of the cast Lyman 375167 in the Mannlicher Schoenauer today. Did not have very good results. They are cast from 1# monotype to 2# lead for a Bhn of about 14-15. This is a plain bottom bullet of about 273gr. I sized them to 0.377" (about 1-1/2 thousandth over bore size) and lubed them with Tamarack lube (50% beeswax and 50% Alox).

I shot some with IMR4064 powder starting at 38.0gr and going up to 45.0gr. I shot some jacketed before going to the cast and the gun was shooting well. The 38.0gr cast was a little worse than jacketed, but not too bad. 40.0gr was noticeably worse. I ended up shooting at the berm after than since I could not keep it on the paper. I checked the bore after each shot and did not see any leading. When I got home, I cleaned it up and did not find any flecks of silver on the patches either. I don't think that leading was the problem.

The velocity at 38.0gr was just under 1,900fps. When it started spraying, I quit shooting through the chrono, so I don't know what velocity it got to. I am thinking of working down from 38.0gr and seeing if I can get a good group. Any other suggestions for the next test?

Loaded up some more from 38.0gr down to 35.0gr of IMR4064. The accuracy got better the lower I went. At 35.0gr, the velocity was just barely over 1,800fps and wthe accuracy was nearly the same as what I have gotten with jacketed bullets.

Looking back, it looks like the accuracy is OK at 1,800fps, is declining seriously by 1,900fps, and is nonexistent at 2,000fps. I think I will try heat treating some bullets and see how they work.

"Loaded up some more from 38.0gr down to 35.0gr of IMR4064. The accuracy got better the lower I went. At 35.0gr, the velocity was just barely over 1,800fps and wthe accuracy was nearly the same as what I have gotten with jacketed bullets."

......You should be gratefull you got good accuracy at 1800 fps with this PB boolit. I do not believe making it harder is the answer, unless you just want a harder boolit. I doubt you'll see any appreciable accuracy improvement As the pressure increase required to see another 100 fps makes any BHN increase fade to comparative insignificance.

You'll need to make a fundamental change to the boolit or your load. Easiest would be to merely switch to a GC design. Otherwise, using the current PB design, if the boolit base position within the caseneck allows it, I would add an LDPE wad or an upside down GC. Then start back at 35.0grs of IMR4064 and work back up.

If the seating depth precludes the use of a wad, then we're either back to a GC design or possibly switching to a slower powder. But I don't hold out much hope for the later.

............Buckshot

I have already checked and did not find a suitable gascheck design. Most bullets in this diameter are made for the 38-55. They won't work. Even this bullet is not perfect. The front lube groove has to be placed outside (forward) of the neck.

I had not thought of placing a gas check upside down, though. I understood from Veral Smith's book that at least part of the reason for a gas check was to act like a wrench, gripping the bullet and the rifling. Do you use glue to keep it in place until it gets into the bore?

Actually, I was looking for a PB bullet I could use as an understudy for the jacketed ones. I am shooting them at 2,160fps with good accuracy.

Harry. have you considered the RCBS #37-250-FN? It casts out at 275 gr. in WW and is quite accurate in my Ruger #1 .375 H&H. I have two of the molds, one giving a .376" diameter, the other .379". So far, I've just been using the larger diameter bullet, lubed with Lyman's Magic Orange sized, IIRC, to .378". It's been a good bullet for me.
Paul B.

Don't think that one would work. I would have to leave about half the lube grooves out the front of the case and that would also leave a lot of places for the bullet to hang up going from the magazine to the chamber. I passed up a Lyman 375449 mould that was very similar for that reason.

Harry O-
Go to www.neihandtools.com and look at
.375-280 GC #180A. This was designed for the 375 H&H and is a good shooter. You can get the PB or GC version in the same mold.