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I have acquired a 270 Maxi pistol and was wondering if anyone had load data. I can extrapolate loads using 7 TCU load data dropping down 10% as the case capacity to the neck is the same.

Thanks in advance.

I think aggshooter has one of those and can probably help.

stubshaft wrote: Tue Oct 29, 2019 12:47 am I have acquired a 270 Maxi pistol and was wondering if anyone had load data. I can extrapolate loads using 7 TCU load data dropping down 10% as the case capacity to the neck is the same.

NO, DON'T DO THAT. I think you have some bad info. Body diameter is very close, but the 7tcu is much longer from rim to shoulder, by about .170".

The 270 Max is my favorite silhouette caliber outside of the BR/bolt gun family.

The load I originally got from Jim Rock was 21.2 grains of 2015 and a 140 bullet. My groups with 15" EA Brown barrel were outstanding, but I have since backed it down to 20 grains. Not significant difference in accuracy (in my 10" gun) but much less bark and I think better case life. I haven't shot the 15" TC barrel in several years, but it always had a brake and a heavy scope on it.

For chickens & pigs, and sometimes turkeys, I run 15 grains of SR4759 (discontinued powder, I buy every can of it I can find) and Sierra 130 pointed soft point. Good accuracy, mild recoil. I have been told that 5744 is very close to 4759 for reduced loads, but I have over 30 pounds of the 4759 so it will be awhile before I try that. I also have used 115 grain Midway blems and shot well, a bit more mild for standing. Probably Hornady made but not sure. I have shot outstanding groups with the 20-21 grains of 2015 with light bullets down to 90 grains. And wow, when you've been shooting 140's and switch to 90's, there is an amazing difference in recoil!!

Don't be afraid to be unorthodox with the seating depth. My custom EA Brown 15" shoots shotgun patterns with the bullets on the lands. I back them off .080" (you read that right, 80 thousands) and they shoot inch groups at 100.

I also FL size every time. If you shoot hot loads, the web will swell just a bit and make it difficult to chamber. Never tried neck sizing only.

Good luck and enjoy a great cartridge!!

Thanks aggshooter. I've been shooting 150's ahead of 21.0 grs XMR 2015. I was just wondering if there were any other powders out there. I am down to my last 9 lbs. of SR4759 and that is dedicated to my 7mmBR.

the closest powder to SR4759 is AA MP5744. But MP5744 has 2 annoying problems, 1 is that it is very expensive and the other is that it leaves kernels of powder in the barrel with low pressure loads. the higher the pressure of the load, the less kernels it leaves.

I use MP5744 in the 357Max with cast bullets and it works well.

another powder that may work is IMR-4227, but it is slightly slower burning SR4759.