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PAPERKILLER
08-27-2014, 11:25 AM
I have been shooting F class with my Savage model 10 .308 that I built with a Shilen heavy 26" barrel for almost a year now. I have been shooting cheap (Hornady, Nosler 155 & 168 bullets at 600 to get a handle on wind reading and to keep expenses down while learning. I have come to the conclusion that .308 is a bit too much recoil to shoot upwards of 70 rounds a day for a 600 match. Plus the ballistics are not that great compared to some of the other choices out there. I am not shooting off a bipod (F- T/R) so am not limited to this round. I have been thinking about rebarreling in a couple of other calibers. 260 Remington seems like the simplest choice as the 6.5 bullets have much better ballistics in general, I can use my same head space gauge and I can still use the Lee Collet neck die that I really like. The other choice would be 6mm br. It has excellent ballistics, is very efficient as far as powder is concerned, and seems to be very accurate. Both rounds get good barrel life which is important as I will probably have to change barrels every 18 months or so. So this is my thinking up to this point. Any thoughts along these lines would be helpful.

foxx
08-27-2014, 12:02 PM
Based on what I've read and my own rifles, MHO is right there with yours, though I have never even been to a competitive shoot.

I like both cartridges, for purely target purposes, maybe the 6BR is better.

I would seriously consider 260AI over the 260, though. Better case life and less prep due to almost no stretch.

LoneWolf
08-27-2014, 12:06 PM
6mm chamberings have been eating up the competition lately it seems. The 115 DTAC and 105 or 115 Berger VLD have been a go to. Even less recoil than a 6.5. 6BR, 6BRX, 6XC, 6CM, even 243 seem to be popular. Big with the 6's is what they lose in BC to the 6.5's they make up for in velocity. with a 243win and 115gr bullets and a 27"+ barrel 3100FPS is easy and great for 600yds or 1000yds comp. Only down side is decreased barrel life, but if you start with a 30" barrel you'll be able to have it reset a few times.

If sticking with the 6.5's the 260, 6.5CM, 6.5-284, are all great. Lots of options out there for sure. Even some other wild cats.

PAPERKILLER
08-27-2014, 12:22 PM
Most of the guys at my club are shooting 6mm Dashers. I just don't know if I want to deal with fire forming brass and I don't know if I quite understand the process well enough. The 260AI does look very promising. I have the same trepidations there. So for Ackley Improved, you just need a chamber for AI and the dies to go with? I have been really spoiled with the .308. I full length size once, then use the Lee collet die for 4 or 5 firings, then anneal and push the shoulder back a little. I have been getting 12 to 15 reloads before the primer pockets get loose....

foxx
08-27-2014, 12:29 PM
I don't really consider 260AI a wildcat (though it is, technically). I just use Lapua 260 brass, fire form with a stout load, seated long in the AI chamber (for maximum pressure so as to form it well), fire, and I'm done.

I use Lee collet neck sizing die for 260, RCBS and/or Lee 260 for seating and a redding FL 260AI die when bolt lift gets heavy. (rarely).

I anneal every 2-3 loads.

It's "wild catting for dummies", I think.

stomp442
08-27-2014, 01:41 PM
What foxx says. 260 Ackley is a great cartridge and very efficient. 2950 fps with a 140 vld is tough to beat in the wind and only using 42-44 grains of powder to do it makes it easier on the shoulder for sure. The 6br is a great one too and proven to be a winner. Its a tough choice but either one will make you happy.

PAPERKILLER
08-27-2014, 08:58 PM
So foxx, if I understand you correctly; you use standard 260 brass (lapua of course), seat a bullet well into the lands with a medium to stout load and this will fire form the brass to the AI chamber? Then I can use a Lee collet neck die for a regular 260 case and resize just the neck as per usual? I would still need a AI full size die to push the shoulder when the bolt gets noticeably stiff? Getting 2900 FPS from 140 grain high BC bullets sounds great! Thanks all for the input. Any other info is welcome.

foxx
08-27-2014, 09:05 PM
Paperkiller, yes to all except use a hot load. Medium may not form the case properly. Keep in mind some of the pressure of a hot load will be spent just pushing the brass out, so go ahead and use the top-end of whatever load your choice of powder calls for with your bullet.

Hornady 140 A-max or Match work well for me.

PAPERKILLER
08-27-2014, 09:26 PM
Thanks for the info. I was reading about fire forming with cream of wheat. You wouldn't have any barrel wear or projectile cost, sounds messy though. I'm not sure I want to be cleaning Crisco and oatmeal out of my barrel and maybe my action. I would imagine the barrel life would be slightly shorter with the AI, but the idea of a flatter shooting rifle is tempting....

foxx
08-27-2014, 09:46 PM
Ditch the cream of wheat deal. pointless. Saves a few bullets and there is no evidence it conserves barrel life any more than firing real bullets. Besides, even when fire forming, you will still get pretty good accuracy. Very close to your final load accuracy. Besides, practice is good.

AI does not shorten barrel life. It's no different ta regular 260 in that regard.
FIREFORMING 200 cases is 200 fewer shots your barrel would otherwise have in it's lifetime. FIREFORMING 50 cases is 50 fewer shots your barrel would otherwise have in its lifetime. But, again, those shots aren't wasted. They're practice. :)

Moreover, you'll save money on brass. If you get 2-3x the number of reloads out of 260 brass, you're potentially saving hundreds of dollars in brass!

stomp442
08-28-2014, 12:12 AM
I agree again. I have done the cream of wheat thing in the past but in the end cases are only about 95% formed and you still have to break in and load develop anyways. What I do now is buy a cheap bullet in the weight I want to use ala hornady sst and fire form as I break in. This way when your done fire forming 50 cases your barrel is also broke in and ready for load development. I save the other 50 cases so that when its time to clean I shoot three or four to re-foul the barrel and fire form at the same time. This way after a while all 100 cases will be fully formed and ready to replace the original 50 as needed. As fox says 10 or 12 firings is easy to get when annealed every third time or so.

PAPERKILLER
08-28-2014, 01:23 PM
Thanks stomp and foxx. Some really good info to think about. I like the idea of fire forming and breaking in the barrel at the same time using cheap bullets. Sounds like you can get good enough accuracy to practice and do some load development as well. Thanks again for all the good thoughts on this. I'm definitely leaning toward the 260 AI now.

CharlieNC
08-28-2014, 03:45 PM
The 6BR is tough to beat in terms of inherient accuracy, easy load development, and relatively low loading cost (eg 30gr powder is it); it does give up a little vs the modified versions if you're serious about 1000 comp. Just follow the suggested loads on Accurateshooter.com and you will be close on a good starting point. The 6.5x47 Laupa is another good candidate; it gets 260 performance with a bit less powder. I use mine for long-range steel, and have 140VLD at 2900fps ready for hunting season too! You can shoot the 6BR all day with light recoil, and the 6.5 is a bit more but significantly less than the 308.

jsthntn247
09-05-2014, 03:26 PM
Are you wanting to stay in Tr or actually try and compete with the unlimited budgeted open shooters. I'd say get a .223 bolt head from Ptg and put a 1:7 twist barrel on there and have it throated for the 90vlds. Little to no recoil and better ballistics when compared to a .308 shooting 185 juggernauts. You can stay in f/tr with your bipod and you don't have to go out and buy a high doller front rest. Mine will be ready next week hopefully. My .308 is now reserved for 215gr bullets and 1,000 yard competitions which I might shoot 2 per year.

Alleycat72
09-07-2014, 08:19 AM
6x47 Lapua.

JASmith
09-08-2014, 09:41 AM
A number of folks have been successful with the 6.5 Grendel out to 600 yards in F-Class competitions. They are good shooters and have learned that only the best beat them at 1,000 but the lower muzzle velocity means that excellent shooters with cartridges like the 7 WSM will beat them at 1000 yards on windy days.

That said, the paper ballistics would suggest a heavy VLD in the .243 or the AI version will do extremely well. For example, the Hornady 105 gr A-Max at 3,000 fps gives slightly less drift than the 190gr 300 Win Mag Berger VLD at both 600 yards and 1000 yards. The recoil is more like that of ... (you guessed it!!) ... the .243 Winchester than the 300 Win Mag or the .308 Winchester.

You will want to use a barrel with a faster than standard twist, however.

Switchbarrel
09-14-2014, 01:22 PM
Most of the guys at my club are shooting 6mm Dashers. I just don't know if I want to deal with fire forming brass and I don't know if I quite understand the process well enough.

I would suspect those Dashers are also beating you regularly. The Dasher with a 105-108gr. bullet is a hard to beat combo. Before I built my first one I was just as nervous about the case forming as you. Now that I've done it, the fear was just of the unknown, it's not difficult. Case forming I've done both the pistol powder/cream of wheat/paper towel method and the 6BR load jammed and shoot method. They both work. If you spec. out a tight/minimum neck clearance chamber, the cream of wheat method will allow you to form prior to turning the case neck if desired. I neck turn first and take it past the neck/shoulder junction to not worry about the "donut" so much.

FWIW- Looks like there's gonna be some factory made Dasher brass in the coming months. Might need a new reamer though.
http://forum.accurateshooter.com/index.php?topic=3853454.0


-Rick

JASmith
09-15-2014, 08:33 AM
The Dasher looks interesting, but there is a possibility the velocity is over-hyped a bit by some enthusiasts.

I noted one source showing 3080 fps for the 108 Berger. That beats the 243 Winchester unless one goes to a 28 inch barrel. The dasher has about 75% of the case capacity of the .243 Win, so the numbers are going to be more like the 2900 fps reported in other sources.

Even so, 2800 to 2900 fps with that long bullet will turn in some outstanding wind bucking!

LoneWolf
09-15-2014, 09:12 AM
The Dasher looks interesting, but there is a possibility the velocity is over-hyped a bit by some enthusiasts.

I noted one source showing 3080 fps for the 108 Berger. That beats the 243 Winchester unless one goes to a 28 inch barrel. The dasher has about 75% of the case capacity of the .243 Win, so the numbers are going to be more like the 2900 fps reported in other sources.

Even so, 2800 to 2900 fps with that long bullet will turn in some outstanding wind bucking!

you'd be surprised because other cartridges like the 6.5x47 will turn in the same numbers as a hot 260rem even with it's smaller case capacity. Sometimes you just get a fast barrel.

Jamie
09-16-2014, 07:49 AM
I would suspect those Dashers are also beating you regularly.

+1

Dasher, XC, 6x47 Lapua, 6mm Creedmoor.......all of them are better choices. for what you are wanting, especially if recoil is an issue.