Picking a new caliber for comp rifle.....

[fastex500]

So I have been reloading for years and have stuck to 223, 308 and 300WM. Running long range precision matches I have seen the dominance of 6mm and 6.5mm cartridges and have decided to take the plunge. I am pretty set on a 243, but wanted some extra input.

One of my reasons for 243 is powder choices and brass availability. I have 4895, 4064, Varget, RL15, RL22, H1000, PP2000 and PP4000 available. I know I can run the heavier bullts in 243 with some of the same powders I use in the 300WM, so I can keep my powder selection down. Is there any reson to look at 6.5CM or another caliber?

My main requirements are:

Common powder usage with current loading supply
Easy brass access (and less expensive)
lower recoil than current 308 and 300WM
better ballistics to 800yds than 308

Thanks for any input!

 

[Sheldon N]

A 243 Win with H1000 and 115g DTAC's would be a pretty good combo, maybe 3000 fps with a fullish case of powder and likely good barrel life if you didn't' run max pressure.

One other option to look at might be the 6 SLR. You just size down commonly available 243 brass and you're good to go, no fire forming. Similar case capacity to the 243, but it gives a 30 degree shoulder so a little more efficient of a shape and less case trimming/stretch.

One of the top shooters in our regional PRS style league shoots a 6 SLR with the 115 DTAC's.

 

[Gina1]

Look into how long a 243 barrel will last. I thint you wI'll find they are not used in competition for that reason. 6mm Dasher is a good choice.

 

[22BRGUY]

Here are some benchrest competition events with the shooters and the equipment lists shown at the bottom for each shooter and what they used. Hope this helps

http://internationalbenchrest.com/results/long_range/_longrangeindex.php

 

[dcali]

A .243 is great for what you're after. Just make sure you get a nice fast twist and a long throat for the heavy bullets. Carry on.

 

[Judd]

A 243 Win with H1000 and 115g DTAC's would be a pretty good combo, maybe 3000 fps with a fullish case of powder and likely good barrel life if you didn't' run max pressure.

One other option to look at might be the 6 SLR. You just size down commonly available 243 brass and you're good to go, no fire forming. Similar case capacity to the 243, but it gives a 30 degree shoulder so a little more efficient of a shape and less case trimming/stretch.

One of the top shooters in our regional PRS style league shoots a 6 SLR with the 115 DTAC's.

Great advice here...either will be good, I chose the 6SLR because I felt it fixed all the negatives to a 243.

I shoot a 6 dasher in my benchrest stuff...I know guys are doing it but feeding can be an issue or I would agree that this is a very efficient cartridge and worth a look. It can't obtain the velocities that the 6SLR or 243 can with a 22" barrel, should you want to set one up for a suppressor.

 

[fastex500]

Great info guys, thanks a ton! I will be running a TBAC CB7 on this rig. Haven't looked at the 6SLR, but will now. I have been looking at the 1-8 and 1-7.5 barrels to run the 105 and 115's. I'm also gathering that I can run the 95's as well in the faster twist barrels.

Barrel life is somewhat of a concern, but I knew it wouldn't be a long life cartridge with any of the 6mm. I am assuming a 6.5 may give a little more barrel life at the expense of some added recoil.

Once I decide on caliber, then it will be whether to do a RPR or re-barrel my Savage!

 

[johnfred1965]

All good advice and I am a big fan of the 243. If you want more info on different options in calibers, you should check out the Precision Rifle Blog. He covers the PRS comps and what all the pros use. Not only caliber but every piece of equipment needed in a tactical type match.

 

[Patton243]

I have a 243 and I like mine but I use it for Varmint Hunting. I shoot 105 Amax coming out around 3050 FPS with a 26 inch barrel. This cartridge would be my pick too. However, your 6.5s should get a little better barrel life than a 243. My guess is you should get 1500-2k out of the 243 for what you're doing.

 

[Riesel]

I'm surprised the 6 x 47 Lapua didn't show up on the radar.

 

[mac86951]

You'll notice the common 6mm response. 6.5 may carry a little more energy, but to compete with a 115, you'll need something stout like a 6.5x55AI, or 6.5x284. Similar powders, but I too would recommend a 243 with barrel twist to match your needs. Barrel life being the downside.

-Mac

 

[Sheldon N]

I shoot a 6 dasher in my benchrest stuff...I know guys are doing it but feeding can be an issue

6 Dasher is my next PRS gun, have a build in the works. I'm going with the new Bighorn TL-3 action since the controlled round feed and mechanical ejector solve the feeding issues that others have run into.

Regarding barrel life, there's a lot of good info out there about the barrel life benefits of running a moderate pressure (sub 55k PSI) load using a slower single base powder like H1000. The slower powder burns at a lower temp and combined with lower pressure you get less throat erosion.

Run the 6 SLR or 243 like this and you may be able to push barrel life up into the 3000 round territory. Run higher pressure and a faster powder and you can burn up a barrel real quick.

 

[fastex500]

More great info! I assumed heavier mass would erode the rifling quicker, but faster powder and faster projectiles doing more damage makes sense. If I keep a 243 in a 1:8 pushing 105 - 115's around 2900-3000 it would be a marked improvement in external ballistics over my sure to PRS rig running 308 178bthp at 2600

 

[TAJ45]

Wish I could point you to the post re 115s vs 104-108 6mm, well written and substantiated = better results with the latter.
Also, may want to note that Berger recommends a 7tw for their 105s. My Bud is running just short of 3200 in a slightly modded XC in the zeros, ones and twos w/Amaxes of all things. He has desires to approach 3300 w/o wrecking brass using some common sense. Sounds counter intuitive, doesn't it? Stay tuned.

 

[Judd]

Wish I could point you to the post re 115s vs 104-108 6mm, well written and substantiated = better results with the latter.
Also, may want to note that Berger recommends a 7tw for their 105s. My Bud is running just short of 3200 in a slightly modded XC in the zeros, ones and twos w/Amaxes of all things. He has desires to approach 3300 w/o wrecking brass using some common sense. Sounds counter intuitive, doesn't it? Stay tuned.

MR-4000...I can hit 3300 with it in my 6SLR and not be trashing stuff up. I can't tell you how accurate it is because most steel places have 3100 speed limit so I never tested up that high.

 

[fastex500]

That does bring another concern I will have to watch Judd... Matches I shoot are 6 - 8" steel so 3000fps is usually the limit. Also, I shoot for fun more than I compete, so reloading components being easy to acquire and lower cost is important. Looking at the 6SLR, what dies do you guys use, and do most of you form 243 brass?

 

[Sheldon N]

Some more info here... note the potential for needing to neck turn.

http://forum.accurateshooter.com/threads/6mm-slr-dies.3897650/

 

[Judd]

I use a Whidden sizing die and someone here offered to make me a Wilson style seating die so I use that for seating. Forming consists of running your brass into the sizing die...it's simple.

Sheldon - I missed your post above. I've been watching with excitement the TL3 stuff. I am not a big fan of the floating bolt head but that might convince me. Bighorn is saying they have the dasher/brx feeding problems resolved with that action. If the dasher and brx could carry the speed in a short barrel it would be perfect...I might have to try one anyway and just have it long and not shoot the suppressor as often.