Hi guys,

Is there a 260 AI out there based on the 260Rem? I'm at loggerheads with my smith about my 19" barreled 260Rem as he feels it is too short and I'm sacrificinf velocity/stability and performance. I'm looking at shooting 140gr partitions for most of my home shooting and then trying to find a faster 120gr TSX load for abroad.

One of the guys suggested seeing if there was an Ackley Imp'd version in the hope it will pick up some fps's.

Also what is the situation regarding reloading? are different dies required for the AI to the regular 260Rem?

Thanks,
FB

Do a search on the 260AI it has been discussed numerous times. Yes you need different dies. Brass needs to be fireformed. And you might get 1% velocity gain. Bigger cases don't help that much trying to overcome shorter barrels. Look to faster powders to minimize the velocity lost by using a shorter barrel.

Using loadtech it says you will lose around 75fps going from a 24 to 19 using a 140. The shorter barrel will have no impact on stability. Something you hit with it will never feel the 75fps difference.

Hi Ramrod,

I was looking at QL, and it gave me a quite a higher velocity reduction on going 24" to 19". If I remember rightly it worked out at about 50fps/inch

I'm looking for 2700in a 140grain bullet but it doesn't look possible. Closest I'm getting is with H4350.

Of course everything is speculative on the software, and nothing is for sure until the Rifle is built...

Rgds,
FB

quote:

I was looking at QL, and it gave me a quite a higher velocity reduction on going 24" to 19". If I remember rightly it worked out at about 50fps/inch

I don't have quickload and I always look at Loadtech with a grain of salt. What Loadtech says with using H4831 and a Nosler 140 you get 2730 with a 24 and 2645 with a 19. That is 85 or 17 per inch. In actual practice I've never seen 50'per inch except in a couple long barrel LARGE cased magnums. As rule of thumb I call it 25.

I simply dropped from 4831 to 4350 or RL19 and was at 2695. That is only 35fps below the H4831.

But speaking from years of experience with the various AIs at the same pressure in the 308 based case you are going to see 1% or less velocity increase.

Standard pressure for the 260 is 60,100 I see no reason not to load them to 65,000 like the 270, 6mm etc. That will gain you 50-75fps+.

My wife shoots a 7x57 with a 140 at 2700fps. She has taken everything from hog to elk and back to Gemsbok. Can't remember her ever having to shoot twice.

If you like the look and feel of the 19" go for it. What you are hunting will never feel the difference. My key statement is don't expect an 260AI to make any difference other than buring a little more powder.

One last thought. Based on the performance I've seen in my wifes 140Accubonds I sure would consider going to the 130Accubond and using it for all your hunting.

High sectional densities of the 6.5 bores allow one not to need high velocities to take down game reliably...

the beauty of any 6.5 round and the bullets available, is the older 6.5 rounds were at much lower velocities.. and proved quite lethal, even on very very large game...

look what they are been used on it Africa and in Scandanavia.. Moose, Polar Bear...

Skip the AI.. If you are using a shorter barrel, consider using faster powders, as they will burn quicker... 4064, 3031, 4895 RL 15, Rl 7 ranges will work well in a shorter barrel..even 4198 can produce some decent velocity and very accurate loads.....

I can see your gunsmith's point, but he is not the guy carrying it hunting...

using 6.5 x 54 data in the 260 and you should be just fine...

those 6.5 bullets are also flat shooting without the need for high velocity to accomplish it.....

Good points Seafire. The numbers I keep hearing (I'm not a fan of computer generated info) is 4 to 1, ie you must increase your powder capacity 4% to increase your velocity 1%. IMO, you're trying to fix what ain't broke.

Fallow Buck,

I am a handgun hunter. I shoot a 6.5 Mini-Dreadnaught, which is based on an improved 220 Swift case. Case capacity is a little more than your 260 Remington. 50.0 grains of VV N560 powder produces 2,533 fps with Nosler's 140 grain partitions out of my 13 inch pistol barrel, and under an inch in accuracy at 100 yards, so I don't see your 19 inch barrel as being a problem or a limiting factor. That powder charge is 2.0 grains below the listed maximum load for my gun by the way. I could get another 100 or so fps, but the accuracy wasn't there at the higher pressures and velocity with my barrel.

Here is something handgun shooters learned a long time ago: The least velocity loss is realized in short barrels by shooting heavy for caliber bullets using SLOW burning powders.

The load/powder combination that produces the highest velocity in rifle length barrels will also produce the highest velocity in pistol length barrels. Maximum camber pressure is reached before the bullet travels an inch or two down the barrel with any powder. Long heavy bullets, with long bearing surfaces, allow peak pressure to be maintained longer with slow burning powders, allowing short barrels to come closer to the longer barrels in their velocity production when loaded with heavy bullets and slow powders...Rusty.

quote:

The numbers I keep hearing (I'm not a fan of computer generated info) is 4 to 1, ie you must increase your powder capacity 4% to increase your velocity 1%. IMO, you're trying to fix what ain't broke.

I agree computer info is a guess. Over the years I did a lot of pressure testing with various factory and AIs using the same barrels trying to keep everything as close as possible. At equal pressure. I got 1 for 4 in the 06 based and a touch better in the 7x57 based. The 308 was closer to 1 for 5. It basically has an AI taper to begin with. While I have more wildcats than factory I would not suggest any of them for much real gain over the factory parent.

Is the 6.5-284 an option here?

quote:

Is the 6.5-284 an option here

Short barrel more powder? Loadtech calls it close to 2800 with a 140 from a 19" IF you can seat the bullet out. If you are limited to something along the lines of the 260 OAL they you are around 2725. So more powder and small gain.

FB,

.260 Rem AI Article

Regards,

Pete

quote:

260 Rem AI Article

Interesting the velocity he quotes for his 139 load is 160fps faster than what Loadtech gives and is listed as only 59,000psi.

Makes me wonder how much he is gaining from a slick barrel and tight chamber.

I learned years ago never argue with someone's velocity claims. I wasn't there nor do I know how close the std and AI are to being the same as to chamber size. Barrel etc.

I can only state my experience.

FallowBuck..I have 2-- 6.5x55 sporters built on turk action, one with a 23.5 inch barrel and one with the very short M94 swede barrel...its about 18-19"...I checked my loads on my chrony in both rifles and with identical loads in my rifles I lose 40fps/inch of barrel...

I will echo what others have said..you don't have to have heaps of velocity with the 6.5 to kill stuff very dead... My little short barrel twede is very effective on deer out to 200yds...load yours up and go hunting...

Z

I have a 260 imp in a 23" barrel and a 16" barrel. I find the vel drop to be a little less then the standard 260 when going from 24" to a 16". I think the sharper shoulder might help in ignition of the powder. Anyway, all 4 rifles used in my above findings have differant barrels ect, so nothing can be claimed absolute. I know my 260 imp would not do the vel that were listed in the article above, and I worked up my loads with a strain gauge to nearly 65,000 psi!
My 16" 260 rem will do 2600 fps with a 140 and 2750 with a 129 horn. Both with WW 748. What more could you need in a hunting rifle? Actually, I consider the 120 grn just right, I've never recovered a 120 nosler solidbase or sierra from deer, so why go heavyer?

TSJ, your point is valid on a deer bullet selection. Seafire slays deer with 100gr, they all work, the beauty of the 6.5 on deer.

As far as comparing std to ai rounds, a buddy built a custom 7/08 ai, shot slower a good bit than std 7/08. No absolutes, my factory chamber was 'looser' I am sure, perhaps allowing more powder, but barrel tolerances also vary, I can see going AI on 308 based rounds if you want to reduce brass stretch which becomes more an issue it seems the smaller caliber you go, 243's worse than 260/7-08 IMHO.

Re; slick barrels, often I wonder if an identical ctg and bbl lenght is faster in a custom gun, as factory bbls IMHO often create more friction in the bore, given identical land/groove dimensions.
My gut tells me a good custom will fare better in velocity, but I agree, animals won't know whether you start at 2500 or 2900, if the bullet upsets, and you place it well, no problem.

Pete, thanks for the posts on the link, he lives in my state. Read it before, but needed to re-read some things in there.....good info.

I do not mean to overstate this, so please read it as if being spoken in the very mildest tone of voice.

The role of a gunsmith who is making you a gun is to build what you want, NOT to tell you what you should want.

It is okay for him to discuss his views of the gun and its performance with you, but to go farther than that? No. If he doesn't want to do the work, that is fine. And, if what you want is not safe then he should flat refuse it up front if a short discussion shows you really don't believe him.

But, should you take any guff off the 'smith because you want something he doesn't want? Absolutely not.

If that happened more than once with the same smith and me, I'd politely take my gun back home and look around for someone equally skilled in 'smithing and more skilled in customer service.

quote:

The role of a gunsmith who is making you a gun is to build what you want, NOT to tell you what you should want.

I have several AI's. They will run much faster than the parent,..problem is they don't show pressure signs like the tapered cases. So by the time you find the higher velocities, you are running hot.

Now,..from a real world standpoint, my 6.5x55AI gained a lot more speed,..due to the parent being a heavily tapered body. From a 26" PacNor, I easily reach into the 2900's with superb accuracy while NOT running hot. I could get possibly another 100fps, but I know it would be top end and not worth the barrel life.

The 260 has little taper,..so capacity increase would be minimal,...however, with a 40* shoulder and straigh case walls to grip the chamber, the brass will last longer in the AI configuration. I have also been able to use much slower powders in the AI cases than their parents would burn efficiently. This allows better load density for consistency. YMMV

If it's a new barrel, tell the smith to make you what you WANT,..or start telling him how to do his job and see how fast he shuts up.