I bought a big bore 94 in 375 Winchester from a fellow member on the forum and took it out to the range today. I don't often use a chronograph, but with a new cartridge and little published data I thought it prudent.
I have 5 molds in 375 caliber. two are NOE molds both use Gas Checks one cast bullets that weigh 237 grain lubed, the other weighs 287.5 grains lubed, I have a Lyman mold that says it will weigh 264 grains and it has a GC - I didn't try this one yet. I have a Lee mold that supposed to weigh 250 grain - I have not tried this one yet, I also have a plain base mold that casts at 235 grain.
I tried the two NOE bullets and the plain base bullet and 200 grain Sierra load and a 255 grain Barnes load. The two jacketed bullets had the same POI. The cast loads had the same POI only about 12 MOA lower than the Jacketed bullets.
The brass was Winchester, The primers were Remington 9 1/2.
My lead mixture was straight wheel weights.
Note: I had trouble finding data for the cast bullets at these weights.
Here are my results:
237 grain NOE bullet with 19,9 grains IMR4227 - 1,500fps accuracy = B
235 grain bullet no GC - 19.9 grains IMR 4227 - 1,500 fps accuracy = A
287.5 grain NOE bullet - 21.7 grains 5744 - 1550 fps - accuracy = C-
255 grain Barnes 34 grains Re 7 - accuracy = A+ - velocity in fps - 2027, 2034, 2013, 2015 and no read ~ average 2,022.25 fps
200 grain Sierra 33 grain IMR4198 - accuracy equal = B velocity = 2110, 2100, 2111, 2080, 2125 ~ average = 2,105.2 fps
Comments: I was surprised that such a small cartridge would kick as much as it did with those Barnes bullets in that rifle. The rifle weighs 6 lb. according to my digital kitchen scale.
I looked at Ken Waters' Pet Loads January 1979. The 200 grain Sierra load corresponded closely with his results (he didn't say whether the powder was IMR or Hogdon - I assume it was Hodgdon. IMR4227 is supposedly a slower powder than H4227)
The 255 grain Barnes load was 200 fps faster than his with the same load. He called the 34 grain Re 7 the best all-around load and he called the load normal pressure. This was the last load I shot and the barrel was getting pretty warm.
The temperature outside was 84 degrees F and close to 100% humidity. The elevation here is approximately 1,000 feet above sea level.
There was no unburned powder in the barrel and there was no lead left in the barrel. The barrel looks like I just cleaned it after all this range session.
Future:
I do have some Linotype and I may try mixing linotype with wheel weights and try again the 237 grain NOE bullet. I'll also cast using the Lyman mold. I'm going to try to get to at least 1,800 fps with cast loads. The 235 grain without GC and 19.9 grains of IMR 4227 will stay as my light load. I have a lot of Xlox 2500 plus white Label Lube that I'm switching too.
I will try other combinations for the Sierra bullet.
On the 255 grain Barnes load, I'm thinking I will drop to 32 grains and check velocity. I am planning on 1,900 fps as top load for the 255 grain bullet.
Last edited by Bugger; 07/09/20.
