Anyone have any real world load data that they have actually used for the 375-284? I know the 284 case is basically the same as the -06 so 375 whelen data can also be used but there ain't much of that data out there either. Does anybody that shoots this caliber have anything to share and possibly with newer powders? Would really like data for the 235 gr Speer.

I have one I built on a 1910 mex action. 235 speers are what I usually shoot in it. I'll dig my data out tonight and post it.

Thanks

So, as I said my 375/284 is built on a mauser. OAL with the 235 speer in the rifle is 3.050.
58 grns of R15 gives 2550 fps. That is a very mild load in my rifle, but the bullet expands, but holds together well. Off memory, I shot 1 good sized black bear, and a couple deer. Found the bullet in the bear lodged under the skin on the off side after breaking the nearside shoulder. Bullets exited on the deer, but with good looking exit holes and no jacket shards in the meat. It worked very well, so I stacked it in the corner and moved on to hunting with my next wet dream of the day.

Thanks, I was actually thinking of trying R-15.

I know I tried IMR 4895 and AA 2015, must not have impressed me, as I didn't even record it. There are more powders out now to be tried in that burn range, but havnt gone back to it. One of these days, if I live long enough!

I just tried the IMR4895 and like you not impressed. At the cost of 375 bullets was trying to save a little on the load development. A lot of new powders but doesn't seem like any ones given them a try.

Niteman, I think I would try a little slower if your not happy with Re15. Maybe H380, or even Re17. What rifle are you shooting it in?
You may get me going, and I'll dig mine out and try some new loads too.

It's a custom Remington XP-100 bolt action pistol with 15" barrel. Gets lots of attention at the range. H380 was another I had thought of. Was the 58.0 grains of R15 a max load?

Not at all on the 58 grn load. A mex 1910 is apt to be softer then some, and certainly not as strong as an XP, so I stopped at 2550 fps.
I have a crapload of .375 bore cartridges, so just move up to a 375 Hawk or Styer when I want a little more power.

loaded up to 60.0 gr of R-15. Shot 1.5" group with the 60.0 gr load and no pressure signs. Also loaded 57gr to 60gr VV N140 with impressive results so need to load them again to verify the same results. If so the VV N140 was an inch or less for a couple of the powder charges.

Ackleys NO. 1 book will give you some loads, I built one some years ago and I got my best velocity as I recall with IMR-4320 so I suspect RL-15 would be an excellent choice, maybe RL-17 would be even better, With Ackleys book start about 10% low and work up, most of his loads are Ok, but he quotes others who seem a tad on the hot side...common since helps..

I also had a 338/284 in mod. 99 Savages and used 338/06 loads minus 2 grs. the 21 grs was for the 99 action, on a good modern bolt gun or 98 Mauser you can use the 338/06 max loads.

The reason I used a 99 savage was I bought a 99F for $100 that a gunsmith removed a stuck case with a hammer and a screw driver and ruined the chamber, it was in his junk pile, so I bought it took it home and ran a 284 reamer in it and called it good. it was..That smithy is no longer is in business.