I'm trying to decide between these. I have a shot out savage .243 to rebarrel or a Shot out Rem 700 300win. From what I've research so far, they are all within about 100 fps of each other. I was going to go with a 30" in 1-8 or 1-8 1/2 twist for the 107 to 115 vlds. Before spending the $, I would like to hear some pros and cons.

This would be used for up to 1k and would be built to F-class open specs. I would not be shooting it for score yet, but whats the fun in not hitting what you aim at. I currently use a 270wsm for this and it can't shoot a full string without heat issues.

Thanks for input.
RC

If you use your 300 then you will need to either have a new bolt built or purchase a bolt for all of those cartidges. I think you would be able to build a 243 wssm with that bolt face though.

Of the cartidges you listed, If you had a long action I would look at possibly the 6 AI. But you have the short action so I would use the savage, and build the 243Ai due to the fact Lapua brass is readily available. You can build 6 ai lapua out of a 7 x 57, but it's lots of work. The 243 ai gets good reviews on www.6mmbenchrest.com
I am not a big fan of wetherby cartidges. 243 AI, with a 8 twist barrel ment for the 105 g bullets and you should do pretty good.

might look at these

http://www.6mmbr.com/gunweek024.html

http://www.6mmbr.com/gunweek042.html

If you use a long action 6mm AI. Weatherby has that funky freebore, and you cannot achieve their velocities without it, possibly hindering accuracy with it. If a short action 243 AI is the only way to go without seating bullets deep.

if your really set on the .243 i'd keep it 243 win.granted AI give more speed but you pay for it in dies that cost more with more fudging around then necessary(ymho) Ram-rod 340 where you at? that 240 weatherby is out!! build on your savage action,with that nice long barrel you''ll get plenty of MV. save your mag-700 action for another project.. you might what 2 look at the 260 rem. while you mull your choices over. regards

For my 243AI and 6RemAI I used 1/10 twist barrels so I cann't help you with using 1/8 twist barrels. If you go to
http://www.websitetoolbox.com/tool/mb/6mmbr they list calibers and they have alot of shooters using the AI for the 6mm VLD bullets and I think you get a better feed back from guys that actually shoot those calibers. On
http://benchrest.com/forums/ they have a forum just for 1000yd and F-class shooters. Nothing wrong with the site here but good to see what the real world is shooting.

Thanks for the feedback. I was wanting a little more than a 6mm Dasher, but less work than a 6mm-06. Savage I have is a long action so could go to 6mmAI, 6-284, or 6-06AI.

I have over the years gone from a 30-378 to 300 win to 270wsm to .243. I'm finding as I age, I like rifles that do their hitting down range, instead of at bench.

Thanks again
RC

quote:

Ram-rod 340 where you at

Can't disagree with much if anything that has been said. We talked about some of the same issues on this thread.
https://forums.accuratereloading.com/eve/forums/a/tpc/f/...=567108397#567108397

Looking at factory I've always prefered the 6mm over the 243. But for the most part that is a chevy/ford issue. Factory 6mm is loaded to 65,000 243 to 60,000 real world handloads your barrel will show more velocity difference than the two cases. Like others have said the 300 bolt would not work because even the 240Wby has an 06 size head. With the bullet seated out the 22-284, 22-06 and 240Wby have basically the same capacity. I found them to burn a lot more powder heat of the barrel quicker and give you maybe 100fps over a 243 or 6mm and you really need a longer barrel. As to AI using the 308 type case I've only burned a little more powder for equal velocity. I know there are big gains posted but at equal pressure I've never seen them. In my testing of a 6mmAI I saw around 66 FPS gain over a std 6mm in the same barrel.

A tight chamber for either of 243 or 6mm with the throat set for your planned bullet would be hard to beat.

Since I have more wildcats or AIs than factory and love to be different if it was my $$ I would decided on a what factory 6mm or necked down 7x57 case I was going to use along with the bullet and oal. Have a 6mmAI type reamer cut to give me minimum clearance. This would result in longer case life and no need to turn the necks. Barrel if it was a bench gun 26" is fine if I was going to carry it you would lose very little with a 24".

I'm looking at an improved as much for reported lessening of throat wear and case wear than extra 50 to 75 fps. This was also an avantage of the 6mm over .243 as I understood it.

That's for info on other threads, I guess, I used wrong search words as they didn't show before.

I'll be rebarrelling savage and I guess, I'll go with the .243 30" #8 1-8" tight chamber. If this one is not what I want i'll go AI on next one.

Thanks again
RC

quote:

I'm looking at an improved as much for reported lessening of throat wear

I'm unaware of an AI giving less throat wear except if you compare it to its next bigger magnum counterpart.

A higher tapered case like the 6mm will tend to grown in length quicker resulting is a short life. Your decision of going with the 243 gives you basically the same taper of an AI.

Only suggestion I would restate is have the reamer cut for your brass choice. For what you are looking to do a tight chamber is a plus. Or at the very least insure the reamer is cut to minimum specs. If you decide the 243 isn't working you can simply run a 6mmAI reamer in your barrel. Or you can do a 243AI as well.

Hope it all works out for you.

I have been shooting a 6mm-284 for about 10yrs now. I doubt I will ever own another wildcat, but I would not take for this one. 95 gr NP and H-4831 have been what I load; and it has never failed on whitetails or coyotes.

Of the three you listed the 243 AI probably makes the most sense. But with the 6mm-284 in my opinon you can get the same velocities with more conservative loads.

Suerte...Frank

I have heard that the 6AI is supposedly easior on barrels than the 243AI even though it out preforms it by a few fps due to the fact it has a much longer neck??? SOme pretty funky theories out there around the taper of the shoulder forcing more of the blast on the case rather than the barrel.. Just thought I'd throw that out there too.

If you want the highest performance with the best cases and least amount of work than the 6-284 is the right choice. No firefoming and easily necked down Lapua brass. But it eats barels.

If I went with a 30" no taper barrel, instead of a #8 conture. Could I not have a .243 chamber cut in, when throat is gone, have it cut back, rethreaded and rechambered to .243AI, shot out, cut back again, rechambered again, ect.

From what I know, doesn't the throat wear out, but not rest of barrel. If you lost one or even two inches of barrel each time, you could do this several times with one barrel, correct?

You should be able to get 800 to 1,000 rds out of each if careful, I would think.

You could end with a short six with a 20" to 22" barrel for 100 yds.

I'm figuring on tight chamber/ turn neck anyways. I'll talk to smith about if cutting barrel is paratical.

Thanks RC

I would go with the 6mmAI or the 6/284.
Everytime you set a barrel back it lasts about 50% of the time before. It is true the throat "shows" the most wear, but the entire bore is wearing and the muzzle will have alomost the same as the throat for a few thousandts as the gas escapes behind the base of the bullet.


www.duanesguns.com

Of the rounds you mention,
I would go 6mmAI. Never have understood why people AI the .308 case.
But you can get a worth while increase with the mauser case , as well as the longer case life and less trimming.
the 6mm284 would be good too.
I would expect great things from a 105 grain VLD both on targets and game. From a long tube you should be able to get some real speed.
You migh try to find out from a barrel maker what the optimum length is for witchever round you choose.
to much barrel can cost velocity. Once the powder is burned all the remaining barrel provides is unneeded friction...tj3006

quote:

Originally posted by Robert_in_mt:
If I went with a 30" no taper barrel, instead of a #8 conture. Could I not have a .243 chamber cut in, when throat is gone, have it cut back, rethreaded and rechambered to .243AI, shot out, cut back again, rechambered again, ect.

From what I know, doesn't the throat wear out, but not rest of barrel. If you lost one or even two inches of barrel each time, you could do this several times with one barrel, correct?

You should be able to get 800 to 1,000 rds out of each if careful, I would think.

You could end with a short six with a 20" to 22" barrel for 100 yds.

I'm figuring on tight chamber/ turn neck anyways. I'll talk to smith about if cutting barrel is paratical.

Thanks RC

You might want to look at this case
6CM and designed/developed by Joe Hendricks. It is in fact an improved 243, shoulder bumped forward and case neck angle changed to 31 degrees. Joe uses H1000 powder, his loads are not light, but compression loads, and he obtains 3000 - 3050 fps with a 115 gr. bullet. Joe was able to use the combination of cartridge design, slow burning powder, and an aggressive cleaning/polishing technique to obtain over 4000 rounds out of his last barrel. He also set 2 new national records with this cartridge last year, and is currently working on a 6.5 cal. version. Hope this helps, and there are numerous threads concerning this cartridge posted on 6br.com.