Please tell me about your 260 AI

I'm going to have one put together and want to know the good and bad. I intend to shoot 120's - 130's. 2 or 3 contour hunting rifle.

Thanks

There is no bad

What he said, I have 2 one is built on a Rem short action with a #4 contour and the other is built on Kimber with the factory contour, just like all the other 6.5's one hole groups are the norm. I love mine!

I have had a bunch of 'em. Love the chambering. My current one just got a new barrel from the group buy on the Hide. Don't overlook the 140gr bullets. That's just about all I shoot in mine. 8.5" twist stabilizes them fine. I shoot RL17 mostly. Some H4831SC. RL17 gets me 2940 pretty easily with long case life and no pressure indications. You'll love it.

Bob

40 degree shoulders can give issues when resizing.
Heres a version that wont.
http://www.6mmar.com/65_SuperLR.php

dave

What are your expectations of the 260AI vs. the standard 260?

The AI case shape will reduce case stretch, and therefore trimming, which is clearly an advantage if you shoot a lot of rounds. However, since most people don't shoot a lot of rounds, except serious pdog shooters, government predator shooters, pretend snipers, and competitive target shooters, the advantage of the AI case shape is questionable.

As with all wildcat cartridges, the dies are almost always more expensive and the resale value of the rifle or barrel are almost always less than if the chamber was cut for a standard production cartridge.

Many people seem to be gravitating toward the shorter 6.5 Creedmoor in SA builds, so that they can shoot longer, low-drag, bullets without the potential of running into COAL issues with the longer 260 case.

I have one hundred dedicated cases for each rifle that I reload for, so that is thirteen hundred dedicated 260 cases currently in the rotation. All of these cases were resized from Norma or Winchester/Olin 243 parent brass, using Imperial Wax. In the sixteen plus years that I've been reloading for the 260, I have not felt at a disadvantage when I've done my part.

No expectations 260Guy. just want one and picked up a set of dies for a couple more bucks than the standard.

I don't expect to sell the rifle or barrel so I'm not conserned there.

13 different 260's certainly shows a committment to a cartridge and I just might ask to pick your brain when it is done.

Thanks

I love my 260 Ackley, I just am not getting the speed I expected, it's actually a lot less. Maybe I just got a bad slow barrel, anyhow, mine has a lot of rounds thru it and when it's time to rebarreled I will go back to the 260 Ackley, just gona use a Broughton this time.

I have a 7-08ai and a 7-08. With 120-130 gr bullets, you should expect to safely get 50, maybe 75 fps over the standard cartridge. You will only get about a 3 grain gain. That being said, the little extra oomph is nice, less trimming is nice, and fire-forming is what it is. Personally, I decided not to AI my recent X-bolt purchase, but if it was already AI'd I'd like it even better. Basically, you can safely halve the velocity difference between a standard 260 rem and a 6.5-06 or 284.

What's your .260AI, RL-17 load with 140's?

I really like RL-17 in my 26" Krieger 6.5-284 and want to try it in my new build, a 23" 6.5x55 Shilen/FN, 8 twist. 48.8 gr. RL-17 in the 6.5-284 gives a solid 3K fps with 140 VLD's and low S.D.'s, 1/2 MOA performance to 400 yds. without pressure signs. Lapua primer pockets tight after multiple loadings.

I read one long range target shooter claim that with RL-17 vs. 4350, recoil was smoother and he could watch bullets land thru his scope much easier. With this load, I can watch bullets hitting the 400 yd. target thru my Z5 3.5-18x44 at full power. And that gun, a hunting sporter, weighs slightly over 9 pounds all up.

I would think .260 AI case capacity would be pretty close to 6.5x55.

DF

Dave/All

I am wondering why the 6.5 Super LR hasn't gotten more press? I've been toying with putting together a rifle to use to learn LR shooting and turret twisting. I was thinking 308, but then started looking for something with less recoil and that would burn just a bit less powder/cost less.

Anyone? Anyone? Apologize for hijacking the thread...

Thank,

Bob

That Super LR certainly looks like a winner!

Fireforming ackleys is for the birds. Talk about a waste of powder, components and barrel for 75fps.

You can still shoot and kill stuff while "fireforming". It's not a shot into the dirt.

I'm looking at building a LW rig in this caliber for my next project. Can the 260 AI be built on a short action, and still run 140s in the 2900 fps range?

You betcha! No problems.

Bob

I always hate quoting loads. No doubt someone with QL will tell me how this load is an atomic bomb. Second barrel on this action. Among other loads, I have gone through 2,600 140gr A-Maxs on 300 pieces of brass. Obviously, even though it's safe in my rifle, start low, etc.

Lapua brass
Federal 210M
44.1gr RL17
140gr A-Max
COAL 2.875"
26" Bartlien 8.5" twist
Suppressed
2942fps 10 shots, SD - 11 (Magnetospeed)

Bob

Yes, but in every Ackley I have owned the velocity and point of impact were not the same between the two. So if you want to reconfigure your come ups and resight in your scope then that is not a problem. I do not like to do that.

Assuming that all variable factors are equal and loaded to the same pressure levels, the additional three or four grains of case capacity in a 260AI is going to fall well short of the larger case capacities of the 256 Newton, 6.5-284 or 6.5-06.

The 260 is a nice short action cartridge and the 6.5 Creedmoor is even better if you want to shoot the longer, low drag, bullets at longer ranges. Within a quarter mile, 440 yards, I doubt that the average guy could tell the difference between all of them under field conditions. If you can put a bullet on target that is tough enough to penetrate through the rib cage and soft enough to expand and dump its energy within the pleural cavity, you'll soon be punching your tag and field dressing your kill.

That's the direction I'm headed with my 6.5x55, based on my experience with RL-17 in the 6.5-284 and what I've read about RL-17 in the .260 and .260AI.

I also am encouraged by the excellent work by Pathfinder on Gunboards.com. See link.

https://www.24hourcampfire.com/ubbth...41/Re_RL_17_loads_for_6_5x55#Post7945641

I hope to shoot a progressive series of RL-17 loads with 140 VLD's using a chrono. Pathfinder said velocity will start getting quirky before pressure signs. I also read that the tapered 6.5x55 case will produce more bolt face pressure than AI type rounds with almost no taper. Those cases do a better job sticking to the chamber wall.

If I can get 140's comfortably moving at 2,800 fps, and maybe find an accuracy node, I'll be satisfied. One would think the 6.5x55 would match .260 AI performance, but it may not due to the differences in case geometry. I guess a 6.5x55 AI would do that, but I already have a 6.5x284 and have no itch to get into fire forming.

DF

What's the scoop on the Magnetospeed. I've seen it advertised but never saw a report on how well it worked, etc...

DF

It's awesome. It has not missed a shot so far. Works with suppressors. No setting up screens. Stores shot string data on an SD card. When I get home I import it right into Excel. Also you are getting true muzzle velocities instead of correcting for 10+ feet sky screen placement. There're plenty of videos and reviews out there.

Bob

Have you noticed any change in POI or accuracy with it connected? If so, how much? Thanks in advance.

That was a question I had. Hanging something on a barrel may change the harmonic profile. Remember those donut looking devices people put on barrels to dampen vibrations? If they had an effect, and I assume they did, what's the effect from attaching this device?

DF

I'm with you, I'd never think of fire-forming my brass while hunting.

Actually, I have twenty-three 260s, but only thirteen that are currently available to shoot. The other ten are either NIB or just gathering dust, as they are rifles that I am not longer interested in shooting.

Not to sidetrack this discussion, but that article mentions all you need to do is run it through a die and it will form case. How will running it through a die increase shoulder angle? Still have to fireform it wouldn't you?

You must be serious about .260's...

It would be hard to come up short with that many...

DF

Yes it changes POI a small amount. It has been very consistent in the change. It doesn't bother me in the least though as it has not effected group size that I can tell. This may be because I almost always shoot with a suppressor anymore. It is very handy to setup and start shooting without putzing around with screens anymore. I really like it. YMMV

Bob

Tell us more about your suppressor.

DF

There's some discussion here. My .30 caliber suppressor is a titanium Sandstorm by GemTech. It's rated for .300 Win Mag. I think it weighs about 13oz. Could be off a little on that. It is direct thread. The POI offset is extremely repeatable. I shot a 5 shot group once, removing it and replacing it for each shot. A real PIA. No POI shift for any of the shots. I shoot it on .308, a couple of .260AIs, .243, .22-250. All with very good results. All hearing safe for the shooter. A side benefit is it acts as a fantastic muzzle brake. Reduces recoil and blast. As I stated in the other post, there is still the supersonic crack that I'm not concerned about. I try not to shoot without it anymore.

Bob