243/6mm rifle build...thoughts?

IMO, if a 6GT is a consideration, then the 6CM would logically should be as well. I have built several 6CM on Rem 700 actions and they have all been great shooters (<1/2 MOA). So easy to load for, and they handle longer and heavier bullets than the 243. When I pull the trigger trhe target never knows what supporter cartridge is stamped on the barrel.

It does sound like you just need a new .243 barrel. Typically when discussing alternates of the .243, I recommend more speed for hunting (AI, 6-284, SS) or more accuracy potential and size down to BR based case. .243 and 6 creed are more or less the same thing. If one is starting from scratch, a 6 creed is a good option. The BR improved cases get great velocity in longer barrels and are easy to load for with great accuracy. Dies are all part of the 'changing cartridge's' game. You can spend a lot or a little on them.

As mentioned above, look at the 6XC. Components are available and you will be buying dies if you go away from .243 anyway. You will find barrel life is much better with 6XC also. 2 of the 3 barrels I have for mine have 2700-2800 rounds and still shoot very accurately. They have lost minimal speed. As I have said before, if you buy a reamer, get 6XC II for your bolt gun. 6XC reamer is for gas guns. I have been competing with this cartridge for 5 years now and love it.

I'd lean hard towards .243 AI, but I have a soft spot for 243. If you're having a custom barrel turned up anyway it shouldn't be hard to get it throated to be at the lands with the projectile you plan to run, or at least to be able to seat the longest bullet you may run, at the lands with the boat tail at the neck/shoulder junction. I know loading for a satern 1:8 .243 AR10 barrel, I can seat some well into the lands way shorter than 2.810, and am giving up some case capacity there.

I am real olde & have had lots of invective hurled at me so any reactions regarding my cheerful use of my 8 twist 6mm Creedmoor are of no consequence.

I buy once fired 6.5 CM brass, often with small primers, and neck down & turn. I also buy new, small primer 6 mm CM brass. My LGS has abundant stocks of small rifle primers so I can maintain a large stock of ammo & shoot many rounds. The bullet seating configuration of the CM fits better in short action magazines for any rapid-fire needs, than the .243 W. The 30-degree CM shoulder slows down brass stretching and the need to frequently trim cases in comparison with the 20-degree .243 Win, fire forming is not needed. The .243 W is a reputation as being a barrel burner & small primer brass is almost impossible to find. CM dies are easy to buy & cheap. I use my 6.5 CM die as a body die & Lee collet die as a neck die.

I shoot 87 VMax's at about 3350 & a variety of 105's at 3000, at slightly more than 60 K psi, against rodents & steel targets. I keep about 250 rounds of 6 CM ammo on hand. I can buy small rifle primers locally without paying hazmat charges. Brass life is good, small primer brass appears to resist primer pocket expansion better than large primer pocket brass.

The other 6mm rounds may be nice but are boutique like - unable to make easy buys of cheap brass.

No mention of the 6mm Dasher - a frequent winner of 1,000-yard local BR shoots.

Another option....get a new 7.5 twist barrel chambered in 6SLR...you get to keep your old brass. Forming 6SLR is as easy as running it in the sizing die. One and done with a longer neck and better shoulder angle.

I ran a 243 win for 2 yrs in PRS when I started doing it. 26" 1-7 bartlien barrel with 105 Hornady bthp, RL26 powder, 3000 fps. No issues engaging targets out to 1300 yds.

ncwg2boatguy said:

I ran a 243 win for 2 yrs in PRS when I started doing it. 26" 1-7 bartlien barrel with 105 Hornady bthp, RL26 powder, 3000 fps. No issues engaging targets out to 1300 yds.

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Man my 243 will SCREAM with heavies and rl26, and shoots awesome. Only problem is finding it. Big reason I haven't been shooting my 243 or 6.5cm much lately. Only been able to buy rl26 twice in about 4 years, and not nearly enough!

I'd do the 243AI in a 7 twist Bartlein 400MODBB for extra barrel life.

Have the new Barrel throated to the bullet you want to run and shoot those as single shots. This is what I do . Just an idea !

huntinfool18 said:

Get a new set of dies and go 243 ackley. Have more performance and can always shot standard 243 win ammo in a pinch. A 105 at 3300 is pretty sweet. Can always put an extend mag box in and have all the room you need to seat bullets out.

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I agree completely with the 243AI. Huge improvement. Out performs most other 6mm cartridges. Easy fire forming. I shoot mostly 105 -108 Bergers with a 8" twist Brux barrel @ 3200fps. Reduces case stretch and donuts by almost none. No negatives to talk about.

I recommend going to 1:7 if you plan on shooting the hammers in 243AI because it gives you better stabilization on the longer bullet. You can still shoot light bullets for blazing speed with the hammers and they appear to be less jump sensitive.

Maybe 6XC? Don't go creedmoor, it will outrage too many people