300 Blackout loads for Big Bore

[aggshooter]

For those who shoot 300 Blackout.....(I do not).....

I have a 270 Max, based on the 357 Max necked down to .277. It has a larger capacity than a 300 Blackout, but bullets are limited to about 140 grain with conventional twist. I have successfully shot it in Production and Standing with 115-140 bullets, as well as a separate barrel in US with 140 bullets.

Conventional 300 Blackout ammo is 110-125 grain bullets. US shooters typically use 155-200 grain bullets. My question is for the former....when running 125-135 bullets, do you have trouble taking rams? I have a chance to rig up a 14" barrel with or without a hi-rise, and looking for direction. I have an ample supply of bullets 110-135 grain, as well as a lot of 30 cal 150 grain, but few bullets at 175+grains. How important is it to shoot heavy bullets on rams?? My 270 max will take rams with 140 bullets and 20 grains of 2015 powder.

Thanks in advance.

Rich

[kdiver58]

I was using Remington 120 grain bucket 300 blackout for a while BUT if I didn't hit them just right they would not go down. This was out of a 8" barrel. With your longer barrel I think you will be fine. I would not go lighter than 120 grains for a bullet. I tried 147 grain factory ammo but my gun did not like the heavier bullet at all. Pick a load that shoots 2150 fps out of a rifle and you will be good to go.

[braud357]

I have owned (2) 300 Whisper (300 AAC B/O) guns, a 10" factory Contender barrel and a 14 7/8" Lilja-barreled XP-100. I used Hornady 150 SP 13.5 296 in the TC, and used a Sierra 180 SBT - 13.0 296 in the XP. Both loads were supersonic, and I never lost a hit ram with either configuration

[xp-100]

Rich, I use the 135 grain in my 14 7/8 inch xp-100. I have never lost a ram I hit with it. My loads are suersonic and they hit hard. It used to be my go to gun, but I ran into some super soft Hornady brass and it shoved the cartridge forward into the chamber and had a miss fire. When I pulled the bolt back the bullet stuck in the throat and I had powder all in the action, but this was a brass problem.