I agree with Fiftydriver- for a SA the 6.5 WSM would be hard to beat, I built one for myself and am now building a 6.5 WSSM also. Another thought would be go with the good ol 308 lots of good ammo and will get the job done if you don't want to go the WSM route.
Almost forgot the 260 Ackley... another thought as well....
You have a lot of interesting (and worthy) suggestions, doubleD. You can go as exotic as you like, but there is nothing wrong with a plain vanilla 243 or 6MM Rem. If you want something sexy and efficient, Mr Arbuckle already suggested the 243 Ackley with a fast twist. It's so good, (and so popular) it has lost a little of the allure, but hey!
Where do you stand on throat life? If you must have a hot rock .224, my vote goes for the 22-250 Ackley. Great performance from an efficient case design. You could go much higher capacity, but they don't last very long.
Oh the .22hotrod doubters. 22-6mm Imp , 8twist, 80gr SMKS or 75gr Amax. just think only have to click up 18mins to get on @ 1000yds, its a good feeling shooting that lazer across the open valleys. shouldnt have any problems with a 80grSMKS on those animals @ that distance. good luck to you, either way you go, have fun and shoot often.
Kind of the veing I'd be leaning towards... .260 Rem (6.5-08), .260 AI, or 6.5x55 Swede, running 120-130gr bullets around 3k or so. High BC, flat shooting, low wind drift, low recoil, good barrel life.
Another option here.Make a 7 twist 243 WSSM and use the new 115 gr SMK that David Tubb has out.Bc is .585 and a 28 inch barrel will push them 3300 fps.Your short action will work just fine once you get the bolt face opened up(cheap job).
As the other posters have said the fast twist 6mm's obsolete the 22 centefires as far as trajectory and downrange energy or concerned.
If you limit your range to 600 yards the 6BR with an 8 twist barrel is simpy unbelievable shooting 107 Sierras.Flat shooting,easy on barrels,easy to load for and arguably the most accurate 600 yard gun today.
While accuracy is tops I beliee we would all agree on that, there does have to be some terminal performance for game to be cleanly harvested.
I do not feel the Matchkings in the smaller calibers are viable big game bullets. Once you get into the 7mm, 308 and 338 class you bet but not in 22 and 6mm.
I also find your 3300 fps velocity with the 115 gr bullet in a 243 WSSM a bit optomistic in a 28" barrel. Not only is the baring surface greatly increased with these bullets, the very fast 1-7 twist will also limit velocity as well.
My 6mm-284 will drive the 107gr Mk to honest 3500 fps levels out of its 30" Lilja 1-8", 3 groove barrel.
From the data I have studied, the WSSM will not top the 6mm-284 at all, in fact from what I have seen from actual hard data, it is running about 100 to 150 fps behind the 6mm-284.
Combine that with the faster twist and shorter barrel adn I would say the 243 WSSM would be hard pressed to hit 3150 with the 115 gr pills out of a 30" barrel let alone a 28" pipe.
Again accuracy is key to bullet placement but once the bullet lands on the right spot, it still needs a certain amount of energy and expansion to perform on game.
The Mk bullets tend to cave in on themselves and expand to small frontal areas. They often penetrate very deep and in the larger calibers are great game slayers but not in the small calibers in my experience.
Also getting a short action receiver to feed the WSSM rounds when they are not designed for them can be a real pain in the rear. If your buildign a single shot, which I would recommend anyway, this is obviously not a problem.
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