Home Forums Hunting & Shooting Custom Rifles & Wildcats .280, or .280AI, or ?

I am a big fan of the 280 AI. Been shooting and loading for one for 30 years. Having said that, for the purposes you described I would not hesitate to build either one. I reload so I like the straight walls of the AI case. As far a feeding goes, I have a 280 AI built on a model 70 action and another built on a Rem 700 action. I have never experienced a single feeding problem with either. You really can't go wrong with either one.

Agree, this is the Fire...make up a 7mm Wby RPM! Neck up the 6.5 RPM or, neck down ( a couple of steps to do) the 338 RPM brass. That would be a doozy. Having said that, here's what I did...I was jinxed on the 7x57 ( I've had all the factory 7mm rds but the .284 Win and 7mm Wby Mag.( I just could not get the four in a row I tried to shoot right! I wanted what you described, a rifle to be shot more at targets than game. I didn't want a 7mm08 as I had been down that road, and wanted "an accurate 7x57 by jimmeny! ha I had a #2 Shilen SS put on a Mod 70 FWT donor, reamed in 7x57, 9" twist. Left the barrel at 25". I figured if I couldn't get it to shoot like I wanted, I could always have it reamed out to the 280 AI (which I had a Mod 700 Mountain Rifle reamed out back in '94 I believe. Only gained 50fps in that 22") So far, this 7x57 is wicked accurate (I've shot more Shilen than any other) and runs right with that first Mountain Rifle AI (used 150 NBT) with 150 ELDX! Long barrels are cheap velocity makers! Same thing, if one is not happy with them long, cut back all you want! That's just two options for you, but can you imagine what that 7mm RPM would be like? lol

I've had a 280AI for about 20 years and can tell you that a 140gr TSX on top of a case fulla Ramshot Hunter is hard to beat.
Gamekings and Accubonds work great too. My son is starting to hate trimming brass cases and has ask about Ackley'n his 6mmRem.

The only reason I would ever improve a cartridge is for brass life and the no need to trim deal. I wouldn't expect a whole lot of velocity increase, but you will have some. The more taper in the case, the better an improved version will be. A heavy bullet in the 280 improved would be cool, but it still won't out pace a good ol 7 rem mag. Sometimes we try to make cartridges into something they are not and never will be. The 280 ack is cool no doubt, but I'd stick with 150 grain range stuff to keep your velocity and bullet performance. One thing about it is, you won't go wrong with either cartridge.

Had a 6.5x06 that stretched brass like it was its job and would get 3 maybe 4 shots. I had a 6.5x06 improved that I would get 6 to 8 shots per case. Brass life was the same, both rifles shot a 140 vld within 50 fps of one another. I'm running a 280 9 twist right now and I had to trim after my 2nd firing.

I've set back 2- 280 Rems to 280AI and both shot a 140 bullets at 3220 to 3230 with 24" barrels very well with RL23 and 215 primers with RL22 they were 3180-3200.
As 280's only 2970-2980. The other 280AI shot 162 horny bullets at 3070 with 23. I know some guys who shoot 280AI's with 175 Bergers very well at 2970.

Are any of those loads pressure tested?

No. Do you pressure test everything?
Load development just like I've done with probably atleast 75 different rifles and cartridges.

I don't pressure test either, but I do operate more conservatively.

I can get a 140 to cruise 3100 out of my rifle, problem is when I did, the bolt had to be pried open and some of the primers fell out. Like I said earlier, sometimes we try to make a cartridge something it's not.

Have you looked at Nosler Data with 280AI and 140's plenty of loads with 140's at 3250 with 26" barrel

What is conservatively? I load for accuracy as long as I dont get ejector swipes, heavy bolt lift, etc
Freebore matters, bullets, powder etc

Have you considered maybe your combo has a problem? Look around mine are the norm not the exception.
I'm not making anything something its not, I guess Nosler is too.
Nosler data with 22 is 3266 ive shot enough 23 to know its 20fps better than 22

My load from back in the 1980s was 64g of H4831 with a 140g ballistic tip.24 inch Douglas.
3140 fps.
Ran it for about 20 years or so.
Piles of deer died.
Nothing within 500 yards was safe..



dave

Don't expect to use a saami reamer with anything bigger that a 140 bullet and expect to achieve its best speed without atleast throating it for intended bullet.

Then there is the "issue" of .280 AI vs .280 AI Saami.....

Since you are starting fresh I assume you'll go Saami. I have one of each.

Probably all ran away from that fly swatter

Around 63.5 of h4831 is when my bolt started saying stop.

And if I remember right that load was midway up my case neck

With apologies to the OP for going off topic .. I had a 6mm Rem AI .. mine was twitchy as f**k. It was a varmint rig with a 1-14" twist. I had the reamer made for the 75 grain VMAX .. a mistake. Should have gone with a bullet that had less of a pronounced shoulder. 70 grain ballistic tip probably. Anyway, the only powder it was accurate with was Win 760. I could shoot 50-100 rounds with it at the range without any problem but when I'd get up in the clear cuts to shoot squirrels I could only fire 3-4 shells in a morning before I'd start getting wild pressure problems. Never could get to the bottom of it. It wasn't barrel temperature or ammo temperature, those were cooler up on the mountain shootin' squirrels than they were at the range. I suspected hard powder fouling but why would that be an issue up on the mountain but not at the range? Eventually I punted it.