Let me post an update, that I copied in full from the Paco Kelly's levergun site where posted it first.
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Since Barnes doesn't make TSX bullets for the 375 leverguns, and since Kalifornia made it illegal to hunt with lead bullets, in much of the state, starting july 1, I had to come up with something on my own.
So a month or so ago, I started a project and with the help of Marlinowners 375win (known here as NewPighunter) I began work on it.
The first donation came from Barnes themselves. They sent me 5 of the 375 cal 235gr TSX bullets. I did some experimenting on my new lathe. After ruining 3 of the 5, I found a solution. I posted my info on MO's forum and was waiting till I got the funds up to buy a box for my experiment. NPH came through with a donor box. He'll be somewhat compensated, but can't say how, as I do not want this to seem like a payment or as if I'm trying to sell anything here. Just wanting to do research for other levergunners in CA.
Anyway, I finally finished lathe turning all but a few of the new box. Some were messed up as part of a learning curve. Of those, some were loaded by me and tested, some will be returned to the donor and some will go the Barnes, for a hopeful project they will undertake.
Let me start the range report with load data.
The 235gr spire point bullets were not suitable for use in leverguns, so I cut the tip off (about 3/8") and trued up the new, flat nose. Next, and this is where some of the experimenting went on, I cut a new profile for the nose.
I loaded up a dummy round without changing the nose profile, to see if it would feed in my Win BB, but it would not. It would chamber, but the sharp nose got caught and wouldn't feed into the chamber.
So I profiled the nose to a more round ogive. Some of the bullets, as you'll see in the pic, were given a straight taper. Both designs seemed to feed without issue. All bullets came out at or near 185gr.
The two designs are shown above next to a 200gr factory loading, for profile and COAL comparison.
Edit: I prefer the one on the left, personally and it will be my design goal.
After the profile was cut, I used a machinists starter drill and drilled the center of each bullet out to a hollow point of approx 3/8" deep to allow the bullet to expand, since cutting off the tip removed the main section designed to initiate the expansion. The Barnes rep seemed concerned that a flat nosed bullet might not open up, so I addressed this issue with the hollow point.
Next I loaded 16 rounds using H4198. Using the Hodgdons load data for the 375 Win, they list a max charge of 38gr of 4198 for a 200gr bullet. Noticing a distinct pattern of charge increase with coresponding drop in bullet weight, I decided it would be safe to start near the max 200gr load charge, with the lighter 185gr bullets.
I started at 37gr and went up in .5gr increments to 38.5 to test for accuracy, and velocity. Here are my results.
The test rifle is my model 94 BB Winchester, chambered in 375 Win. Range was 50yds, with Williams FP peep sight, with which I'm not a great shot. Field elev approx 3000, temp 68 deg, wind calm.
Here are the posted velocities, the most accurate of which seemed to be the 37gr.
Bullet Barnes TSX, 185gr
Powder H4198
37.0gr
2438
2389
2458
2391
Avg vel 2419
37.5gr
2408
2427
2457
2469
Avg vel 2440
38.0gr
2485
2474
2511
2503
Avg vel 2493
38.5gr
2530
2501
2512
2524
Avg vel 2516
Here's a pic of the 37gr load.
As you can see three shots were very close and the forth a flier. One thing I DIDN'T do, wish I had, was grouped them into nose profile groups, to see if that made a difference, duh.
The squares in the target are 1".
I plan on doing the same thing, eventually, to the heavier offerings for the 375 and on some of the heavy 458 dia bullets, so something heavier than 300gr in non lead is available for my 1895GS.[/b]