Before I go out and burn powder and detonate primers, thought I might ask for a little help. Anyone playin' with the .260 AI? Lookin' for load data in the 120-125 NBT/NP arena. Probably start with an upper middle-of-the-road IMR4350 load but...


Hank

where you at in CO Hank ? And what gun is your AI ?

Colorado Springs, and .260 AI is a Rem 700 (Mountain Rifle)...





Hank

Thanks ...the reason I asked.......I have that same Mtn. rifle in .260 and have considered having it AI'd. Kind of curious what improvements you have seen and if there were any issues that would make you think now that it wasn't a great idea. My .260 will shoot 125 Nosler Partitions quite well but for all around I really like Horn. 140 SSTs and a dose of RL-15.

Haven't really done anything other than fireform cases at this point. Will be taking it out within the next couple of weeks or so and work up some loads, will certainly let you know how it all works out. Tried 125 Noslers and 120 Ballistic Tips before the rechamber and it was about 1.5" @ 2800fps with either one. My smith mentioned that feeding may be "iffy" but we'll see...





Hank

If you dont mind me chiming in, I could offer some thoughts on AI'ing...

If you're looking for more velocity, this is not where to look. Since the .260 doesn't have much of a taper, the case capacity gain is not enough to offer any significant advantage in velocity. Actually, people often will push loads to higher (dangerous) levels looking for the velocity increase that just HAS to be there.

This doesn't meant that there's no advantage to AI'ing...Actually, the AI is the reloaders dream, in the sense of case life. With the minimal (read none) taper, the case just doesn't get worked much at all (providing you do your part at the reloading bench), and that translates into greatly improved case life.

So AI'ing has a few things going for it, but just not in performance. Honestly, you will get a gain in velocity, but it will not be enough to make a difference on game, or significantly alter your tajectroy.

But, you'll get 3-4 times more life out of your cases, a few FPS and still maintain the ability to use off the shelf ammo...All for usually under a hundred bucks...

Not a bad deal if you ask me.

Batman

You are right Bat, I wouldn't spend the money on dies & rechambering an exist. rifle, but if you are rebarelling, why not. There is about a 2gr diff. in case cap. & even if you only get 50-100fps it's almost free.
I've just started working w/ mine & RL19 is looking good for the 120gr pills, H414 for the 100gr.

Cool,

The last AI I played with was a .338-06 AI and it was fun. Unfortunately, the wartime Czech action eventually cracked at the receiver ring...Could be that the smith that built it over tightened the barrel...Too bad, the rest of the gun was built quite well.

One of these days, I hope to build up a .257 AI just 'cause it's cool.