Rebarreling, 260 Ackley improved, or 6.5/284?

[Dialing Long Distance]

I have a Savage model 12 long range precision, chambered in 260 Remington. I am thinking about rebarreling the rifle this coming fall. I am thinking, that for my particular rifle, a 260 Ackley improved would probably make more sense. I have a bunch of 260 brass from Lapua, that could fire form pretty easily into the Ackley improved. What I am curious about, is the accuracy and velocity comparison between the two calibers. Another thing I was considering with 260 AI, is possibly getting the 308 Lapua brass with small primer pockets, and necking them down to the 260, then fire forming them into the Ackley improved, giving me a small primer 260 Ackley improved case. Something I thought I would experiment with.

Am I on the right track with this idea?

 

[codyadams]

I have a Savage model 12 long range precision, chambered in 260 Remington. I am thinking about rebarreling the rifle this coming fall. I am thinking, that for my particular rifle, a 260 Ackley improved would probably make more sense. I have a bunch of 260 brass from Lapua, that could fire form pretty easily into the Ackley improved. What I am curious about, is the accuracy and velocity comparison between the two calibers. Another thing I was considering with 260 AI, is possibly getting the 308 Lapua brass with small primer pockets, and necking them down to the 260, then fire forming them into the Ackley improved, giving me a small primer 260 Ackley improved case. Something I thought I would experiment with.

Am I on the right track with this idea?

No need to get .308 SRP brass, Peterson makes excellent SRP brass for .260, I am currently fireforming them in my .260 AI right now.

As far as accuracy....both cartridges have great/equal accuracy potential in my opinion, I have yet to fire a load in my rifle that groups bigger than about 1.25" at 100 yards, it's a trued rem 700 with a Krieger 8 twist barrel. My load now is 49.1 grains of Reloder 26 with a 140 Berger VLD seated .005" off the lands, which is right about 2.905" OAL, and is going 3070 fps out of my 29" barrel. However, when working up this load I went up to 51.5 grains which is where I started seeing pressure in the form of ejector marks on about every 3rd round, but that was going 3170 fps....my accuracy node ran from 3050 fps up to 3120 fps, about 48.8 grains up to 50.6 grains, all within safe pressure in my rifle, and all loads ranging in there grouped within 3" at 505 yards, with a vertical spread of about 1". I went with 49.1 grains. It groups at or under .5 MOA, If I do a good job it's more like .3 MOA.

 

[codyadams]

I pulled the low one on this group. I could tell it broke at the bottom of the dot

Peterson Brass come in a nice 50 round box and packaged very well, upon weighing I would say it's on par with Lapua, it's made in America, and it's cheaper than Lapua, I paid $80 shipped for 100 rounds. Highly recommend.

 

[codyadams]

Also forgot to mention, since your running a short action, that kind of takes the 6.5x284 option out of the question anyway unless you want to single feed. OAL of that cartridge with any long range bullets essentially dictates that you must run a long action if you are running it as a repeater.

 

[J E Custom]

I originally went to the 260 AI because I wanted all the benefits of the 6,5 bullets and the efficiency of the AI design combined with the ability to use the several thousand 308 cases I had to fireform them to 260 AI. But before I finished the rifle, Lapua came out with 260 rem Brass and this issue was resolved. I prefer the actual/Correct head stamp on the case, and the Lapua brass fire forms great to the AI.

Unlike some, I seat all bullets well off the lands to control pressure and find no accuracy advantage by seating bullets touching or just off the lands. In fact the bergers actually shoot better for me well off the lands as long as I do a good job of getting my loads concentric.

The best primer I have found for the 308, 7/08, 7/08 AI, 260 rem AI has been the CCI Br2. the small rifle primers did not show any measurable difference over the BR2 primers to me. The AI case design "Does" show better powder efficiency and case life and all seem very accurate.

The only down side to the AI design would be feeding in a gas gun. Bolt guns dont have a problem if set up correctly.

Just My Opinion

J E CUSTOM

 

[MudRunner2005]

260 AI