Originally Posted by wvcountryboy
Thanks for all the info guys. This site is great. As you can see by my post count i'm new. I would LIKE to go with a short action. Not 100% on it yet. I wasnt too interested in the gibbs or the 6-06. For some reason i seem to be more interested in the short action. I have plenty of big bore long actions. I have no experience with .243 cal. I'm sure the br would be great, i just have the need for speed. I know i sacrifice a lot for it but I just like it.
I am leaning towards the 6mm remington but someone said the 243 ai shoots greaat. I like the 243 due to all the GOOD brass available. I prefer not to have to fire form cases because i plan to shoot this gun a lot in the summer months so barrel life is an issue. If either of those cases (243ai or 6mm ai) make 200-250fps difference with the 40 degree shoulder... i'll do it.
From some of my research it looks like with the smaller bullets i would actually LOSE velocity with bigger cases such as 6-284, 6-06 and gibbs. Would I have to worry about that with improving the 243 or 6mm? Also what twist do you guys think? I know its better to spin too fast than too slow. Should i go with 10 or 12? Also, for you guys helping me with velocity numbers I plan on a 26" barrel.
food for thought:
not all short action rifles are created the same. They will vary a .150" in length. The Savage will handle a 6mm Remington just fine unlike a Remington 700 using 90 grain bullets seated out to the rifeling. I also seem to remember that the Winchester is longer than the Remington as well.
Most guys I know that shoot the .243 go thru cases on a regular basis do to neck splits (Ackleys seem to be worse). I'm using 6mm remington cases that are close to 15 years old. The 6/250 goes thru a case about every six firings, but I think if I anealed them every third or fourth firing they might last a little longer. The next problem you get is that when you form the .243AI (or really any Ackley case) the overall length actually shrinks about .03" in the neck length. With the .243 already being too short for the caliber, this creates a problem. Alot of guys I know are now using 6mm, or .257 cases to form .243 Ackley brass (most chambers have the neck cut a little long anyway, so you can take full advantage of the max neck length. (.06" will do wonders)
If you just gotta go fast, then at least look at the 6 Vias (70 grain bullet at 4000+fps). The 6/250AI will drive a 105 grain Amax bullet at close to 3100 fps, and still do 1/4" groups at 100 yards (I use H1000 powder with a 1:8 twist barrel) The twist rate needed will parallel the actual bullets you plan on using. A 1:10 will easilly do a 90 grain bullet, but still work well with the 70 grain bullets (I like the Sierra 80 grain Blitz). But if you planning on using the VLD's or low drag bullets you need to step up the twist rate. My 6BR uses a 1:14 twist, and it barely handles the 80 grain Blitz (a 1:12 would do wonders). The 6mm's I've owned had 1:9 twist, but would not handle VLD's very well; yet shot 85 grain bullets like they going outta style.
If I were to build a rifle around a 6mm something, I think it'd be a Savage mod. 12 single shot action. Use the laminated wood stock (the older style with the flat forend). Buy a good used one and order in a Sharpshooter barrel in whatever you decide on (you may have to furnish the reamer if it's a oddball). For me it'd be another 6/250AI, but with a 6mm neck length in a 1:10 twist