I am considering throwing together a hunting rifle, and this time around I'm looking to chamber it in an Ackley cartridge. My criteria are that it is based off of a standard case (.473 head) and falls between .25 cal minimum and .35 cal maximum. I want a gun that is accurate on the range (.5-.75 MOA capable) while still being useful on medium size game(from 50-300/400 yards). Recoil is not to much of an issue, I do own several magnums. Thanks for the help
I put in my vote for .270 Ackley improved. I got my dies from rcbs.
My 270 Ackley improved is a chromemoly 29 inch McGowan 1.250 taper to 1 inch. I was reading on another sight about barrel manufactures. They list all the top 8 and they all use about the same machinery. But little things like correct break in.......... goes a long ways in barrel life and accuracy. They also had doubt's about cryogenically treated barrels.
The things I like about my AI is: I probably should have got stainless, but I don't mind carrying a gun hunting that weights 16 or so pounds with my 8.5 pound barrel, Harris tall bipods, and 6X24 power 56mm scope. My gun is 11:1 twist which is optimal for .277 and 140 grain bullets. What is so nice in heavy target guns is the recoil is so low and straight back that you never come off of the target. on 24X I can see the holes appear on paper up to 200 yards. Out hunting you see where the bullets hits.
I have never recoved a 140 SPBT from any animal they even went clear through elk. neck/spine shots completly removed a vertebrae or two, the chest shots nice exit wounds.
Chronoed very accurate loads @3320 + or minus 6 fps with 61.2 grains of IMR 7828 CCI 250 mag primer. Moly coated Sierra 140 spbt
.270 Ackley improved 29 inch 1.250 dia. target barrel 7mm STW 28 inch 1.250 target barrel. I also love my .458 mag for varmints and the biggest game in the world.
My vote is for a 6.5-06 and improved versions. I am having a hoot with mine (6.5-06) and they will certainly deliver the goods at the ranges you want.
I stuff mine with 140gr SST and spit them out of a 24" barrel at 2975fps. At 500yds, they create a very large welt on the backside of my 5/8" thick swinging steel gong. At 600yds, the onside crater is substantial and the backside does show some distortion.
For weight of bullet, this combo still hits hard. I doubt I would use it beyond 800yds though - a bit light.