Why is the 280AI almost revered?

[Dave Hoback]

I just ordered a new barrel. And I stuck to exactly what I said I would do. It’s getting chambered in 260AI with a .160” Freebore, what they call the “Match or VLD” chamber. This is so I can load them 2.900”+ COAL. Now I decided I would do this long ago. Probably a year AFTER getting my current Shilen barrel in standard 260Rem, & wishing I had done Ackley Improved from the beginning. Through these years, I never changed my mind. (I usually don’t, because my research is sound on what I want.), although I have taken note of many talking down the 260AI. Saying it’s not worth it..better to stick with the 260Rem. And the most popular rant, “switch to the 6.5 Creedmoor.” (Riiight… like that would ever happen! Right… switch to a LESS powerful cartridge. Although, somehow the Creedmoor has managed to “magically” increase velocity by doing absolutely nothing! Somehow loads that were doing around 2700fps 5 years ago, are now claimed to be going 2900fps+++ by on-liners..) So anyway, moving on. At the same time though, praise for the 280AI is everywhere! It’s almost heralded as a great upgrade to 280Rem. I’m just wondering why? Why does a person say “Yes! Absolutely switch from 280Rem to 280AI.”, but in the same breath will say, “NO! Forget the 260AI.. not worth it.” It doesn’t make sense to me. Obviously I know they are different calibers & cartridges. But the performance gains between the two are almost identical. So anyone feel only the one is worth it?

BTW: This is simply a talking point. Obviously I’m not changing my mind, and I’m certainly not trying to change anyone else’s. I genuinely would like to hear a credible reason for one being ok. Because it does seem like bias thinking; which is fine… we’re allowed to have biases towards THINGS. I certainly do.
So do some feel only the one is worth it?

[Txhillbilly]

Some cartridges really are better when Ackley Improved, and the 280 is one of them. Plus, You can buy factory ammo for the 280 AI, and most that shoot the cartridge are hunter's that may or may not reload.
Several years ago, I built a 260 AI with one of my Savage actions. I wasn't impressed with the small gains I had over what I get out of my 260 Remington LR 10. After a few range trips, I took the barrel off the action and sold the barrel, dies, and brass.
I know several guy's that swear by their Ackley Improved 223's & 7mm-08's as well as the 260 Remington, but to me it just isn't worth all the trouble for the small gains in velocity that you get.

Dave, there's a good reason that guy's like myself have gotten vast improvements in velocity with the 6.5 CM cartridge. It's called " Quality Brass"!
Hornady brass always sucked. The large primer pocket brass from Hornady usually wouldn't last past 2-3 mild loads before the primer pockets were shot, and the primers would fall out.
Now that we have Lapua, Starline, Peterson, and Alpha small primer brass, we can push the limit a lot easier, and get higher velocities while still being at safe pressure limits.
I have no problem hitting 2900+ fps using Lapua and Starline SRP brass, but the load that I stay with is the the 2880 fps range.

[charlie b]

The AI thing is cartridge dependent for a lot of reasons. Not sure what the case differences are from .280 and .260 (other than neck dia). Or what the AI dimension change is. Usually it means less taper and the 40deg shoulder, which means more case capacity and longer case life. Some cases are already 'overbore' a bit and the extra case volume results in little gain. The last may be the reason the 260AI is not as popular compared to the 280AI?

I think it depends more on what people do with it. Do they expect to make a sluggish cartridge a barn burner? Or maybe the factory twist won't let them 'use' the extra case capacity to it's full potential?

The CM is one of those interesting ones. Designed for short actions and then hyped up. But, it remains as a pretty efficient cartridge, which usually means better accuracy. Yes, the 260 and 6.5x55 work well for higher velocity and many accurate rifles were produced for them. I was considering a 6CM when I was looking for a 6mm cartridge. It is not too overbore to ruin barrel life, but, it has enough capacity to go over 3000fps with the heavy bullets. Interesting enough, I went the other way with a plain 6BR. The extra velocity made no difference for my use and the extra long barrel life appealed to me.

I do agree that many have a 6.5CM for very wrong reasons, expecting it to take down elk or moose with 'magical' performance. OTOH, there are those in the accuracy game who like the niche the 6.5CM fits in. And whatever you or I think about the cartridge, the various rifle manufacturers had stepped up with premium rifles in that caliber. Several folks at our long range shooting site like their 6.5CM's for the 1000yd performance out of factory rifles. For some it was the first time they moved from the .308 to something else.

[wbm]

The large primer pocket brass from Hornady usually wouldn't last past 2-3 mild loads before the primer pockets were shot, and the primers would fall out.

Has not been my experience at all. I am on 5-6 loads on Hornady brass. So far no issues.

[PhilC]

The 280AI very nearly replicates the 7RM with less powder, lower recoil, and negates the need for belted magnum brass. In most rilfes, the '06 size case nets an additional round in the magazine vs belted magnums too. What's not to like?

[Txhillbilly]

Has not been my experience at all. I am on 5-6 loads on Hornady brass. So far no issues.

I built my first 6.5 CM back in 2009. The only brass available back then was Hornady, and it was horrible when it came to the primer pockets expanding with anything loaded near the top of the powder charge range. There was also the same problem for guy's that bought Hornady factory ammo, and many complained to Hornady about not being able to reload once fired cases because they wouldn't hold a primer.

If you like it, good for you. I'll stick with loading quality brass that I know will give me longevity.

[Robinhood]

I like cartridges that serve a purpose. if you want to shoot prs, go to a prs match and see what the top guys are running and determine if that fits your budget and needs. Want to shoot belly benchrest? Go to a match and observe what is winning. Go to a RMEF Convention and ask someone what they would consider a good rifle for the type of hunt you are going on. The rifle makers and the experts don't choose a cartridge for cool factor. They choose what works.

The current top 7 pro PRS shooters utilize a 6 Dasher. Number 8 uses a 6.5 Creedmoor.

The 280 is a great round as is the 284. Loaded heavy is good medicine. The 280 AI is just better, for reasons mentioned. It is a lot of energy in a smaller package.


As for the 260 AI

You will rarely see ten 260 AI's at a match. You will see many 6BR's or their variants. You will see a variety of 6's and 6.5's. 260's or 260 AI's....not often. You will see guys shooting 6 and 6.5 Creedmoors.

I like the 260. I like the sound of a 260AI. I just don't need it. It fits a niche that does not exist in my life. It obviously suits your needs. I say perfect choice.

But so is the Sweede or the 280.