260 Rem versus 6.5 Creedmoor.

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260 Rem versus 6.5 Creedmoor.

Post by Wyliecoyote » 19 Jan 2023, 9:43 pm

A little while back i fitted a 260 Rem barrel to one of my Defiance actions purely to use for long range shooting of hogs and deer. Bullet used was the 140 Amax/ELDM with 2213SC in Win cases where the length of cartridge was determined by the AI magazine and set to 2.820". Every load shot very well with any charge producing at least sub half MOA. The load i settled on was 44 grains of SC. Now this is the new lot of 2213 SC with the latest temp sensitive additive that has sped up the burn rate very slightly from the old SC. Velocity at 10 feet averaged out at 2640 fps. Not fast but super accurate way out.
All in all easy to load for, no worries if i lose a case where all started life as 308 originally. I always intended to run Reloder 26 through this case to bump up speed over 2800 fps or even reach 2900, but never got around to it.

More recently i looked at the Creedmoor and the arguments for and against it. In an AI magazine, the argument is pointless as the bullet position for both cartridges is identical at 2.820". The only real difference is where the length of cartridge finishes. It is an aesthetic thing where both cartridges set at the same OAL share near identical powder capacity and both are restricted by the bullet seated into the case. In a single shot application where the bullet can be seated long, the 260 has a slight edge. My original concept was to take the Creedmoor reamer out to 308 length where again the OAL will still be 2.820", but the steeper shoulder and less taper gains a reasonable capacity increase. I opted not to do it as fire forming for a hunting rig really is pointless. I even formed some cases to see how much gain there would be prior to firing. Maybe one day i may do it, but for now there is a Creedmoor chambered barrel in the Defiance action.

I started with 2213SC where i ended up with the 260 accuracy load at 44 grains. Not as tight as with the 260 but velocity was for all intent identical. Continuing through to 45 grains it shot a tight clover finishing at just over 2700 fps. Very mild on the cases where i am certain the load could be increased by at least a grain or more.
This time i did load Reloder 26 with the same 140 ELDMs. Those that follow US forums will know this powder gains some serious velocity with 140s, 143s and 147s at 2900 fps and beyond. I started at 46 grains for 2800 fps through to 47.5 grains for 2880 fps with no pressure signs. The yanks go beyond 49 grains with 147s in SR primer Lapua cases for 2900 fps. I think maybe 48.5 grains in Win LR primed cases is about my limit. The accuracy at 47 grains was not measurable with the 3 shots looking like a single bullet hole at 100 meters. This will be retested in a few days at extended range but will most likely become permanent in this barrel.

Something i have seen and known for a long time is that geometry of brass has little to do with accuracy, but a lot to do with sales hype. No doubt that steeper shoulder angles restrict case length growth, but the down side is they are far more prone to donuts. I see no gain over the 260 with the Creedmoor with speed or accuracy potential. The 260 cartridge feeds better though the AI magazine. What is important is powder matching to a cartridge which in recent years has never been so diverse with so many powders available. Reloder 23, the darling of 284 users, in my view has huge accuracy potential in both these 6.5s as well as the now nearly outcast 6.5/284.

Having seen both now, there is nothing in it. The 260 is the economic choice as any 308 brass can be used. If you don't reload, the Creedmoor is the pick with so many factory load options.
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Re: 260 Rem versus 6.5 Creedmoor.

Post by deye243 » 19 Jan 2023, 10:29 pm

Yes I started another thread about the new 2208 and that white s*** that leaves at the muzzle and in the barrel of figure that it will attract a lot more moisture not impressed anyway back to the 260 I have been loading 47.5 grains with the 144 grain hybrid Target burger for several years velocity is 2813 ft per second for an average of 10 shots but that is with 2213sc that is 15 years old and outstanding accuracy similar results have happened more than once this is at 1205 yards
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Re: 260 Rem versus 6.5 Creedmoor.

Post by bigrich » 20 Jan 2023, 6:05 am

the subject of mag length in the OP's post is the reason i went with 6.5x55 in a tikka t3 . it uses a 30-06 length mag and i can seat as far out as as i need too with room to spare . a lot of 308 based cartridges are limited to 2.8" col in lots of rifles due to mag length . my 7-08 t3 went down the road because of this . i was 120 thou short of where i wanted to be with some projectiles. and the rails on a longer 30-06 mag in the t3's are shorter which means a 308 length case jumps up out of the mag too soon and rattles around in the action before it starts chambering . i'm very selective of what rifle actions i go for now . one of the best "old " actions for 308 based cases is the mauser 98 . plenty of room and feeds well . sako 85's and vangaurd/howas have good mag length too i beleive . i'd go 260 rem over the CM if i could find the right rifle. but as i handload for my 6.5x55 tikka i'm happy .
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Re: 260 Rem versus 6.5 Creedmoor.

Post by Wyliecoyote » 20 Jan 2023, 8:04 am

This is the 100 metre group with the Creedmoor barrel. Disregard the velocities, they were mistakenly written in for the 46.5 grain load. Bartlein barrel 26 inches long, Win case, S&B LR primer, 47 grains Re26 and 140 ELDM at 2.810" OAL.
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Re: 260 Rem versus 6.5 Creedmoor.

Post by deye243 » 20 Jan 2023, 2:50 pm

Can't complain about that but how does it do from 600 onwards is the key
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Re: 260 Rem versus 6.5 Creedmoor.

Post by SCJ429 » 20 Jan 2023, 7:41 pm

There is a lot to like about the Creedmoor case, thank goodness Lapua made brass for it or it was in a bit of trouble. I have a 260 AI and lots of guys come over to see what it is. No one looks twice at a Creedmoor anymore as they are nearly as common as 308s. As you say, not much between the 260 and the CM, really comes down to your loading ability.
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