Warlord....
If you can afford it, buy another rifle. If you can't afford it, use the .243., but regardless... get some ear protection. Like Tom said, they'll all blast your ears and you SHOULD wear some good ear protection. Even my little .222 heavy-barreled Sako is LOUD!
If you are going to buy another rifle and the area where you hunt is NOT very populated, a .243... or better yet, a 6mm Remington whose case has a somewhat larger powder capacity than the .243 Winchester and gives a muzzle velocity of about 50 to 80 more feet/per/second (fps) than the .243 Winchester with the same bullet with a 26-inch barrel would put you in good shape for about any "varmint" you wanna hunt.
The .243 Winchester is more popular due to Remington's mistake of bringing out the .244 Remington cartridge, but offering their rifle for it with a 1:12 twist to their rifle's barrel which did a good job of stabilizing the 90 grain and lighter bullets while Winchester "won the game" by bringing out their rifle with a 1:10 twist that would give good accuracy and stabilize the 100 grain and heavier bullets that the .244 Remington wouldn't shoot accurately. The 6mm Remington cartridge and the .244 Remington cartridge are the SAME cartridge... the only "difference" being the 1:12 vs. the 1:9 twist of the rifle in which they're fired.
If I were choosing one or the other, I'd choose the Remington 6mm since it will yield a somewhat higher muzzle velocity using the SAME weight bullets as compared to the .243 Winchester. Of course, I handload and can take full advantage of the extra powder capacity of the 6mm Remington cartridge case. Incidentally, the .243 is a .308 Winchester case necked down to .24 caliber whereas the 6mm/.244 Remington is a 7X57 Mauser case necked down to .24 caliber.
In such a rifle, I'd suggest a Tikki, a Remington 700 varmint rifle or a Savage heavy barreled varmint rifle (a variation of the Model 110 Savage bolt action rifle). I think the Tikki would be hard to beat for a smooth action, excellent accuracy and a "good" trigger, but the Savage 110 varmint rifle variant is also a very accurate rifle and considerably less expensive than either the Tikki or the Remington. You might feel the action isnt quite as smooth in either the Remington or Savage vs. the Tikki (made by Sako).
The money you save if you bought the Savage could be put towards a high-quality variable scope... the high end of which should be at least 15x or even a 6x-24x variable scope. Be SURE to get a scope with an ADJUSTABLE OBJECTIVE (front) TURRET to correct for parallax... VERY IMPORTANT! And get a scope that you can buy extra "sun shades" for... one that you can screw two or three sun shades together on if necessary... you can't HIT what you can't SEE in varminting
and sometimes, those sun shades will be of considerable help in keeping the sun off the objective scope lense.
The 700 Remington is reknown for it's out-of-the-box accuracy, but in all honesty, I doubt that the Remington 700 varmint rifle is quite as accurate than the Tikki or the Savage. But it is a fine rifle capable of excellent accuracy.
As concerns caliber in a new rifle... I'd stay with the .24 caliber rather than the .22 calibers (actually .224"). Why? The effects of the wind and a slightly heavier bullet (in the .24 calibers) which will not only "buck" the wind MUCH better, but maintain it's velocity better due to a higher ballistic coefficient. I seriously doubt that many people could "tell" the difference in the "blast" of a .22/250 vs. the muzzle blast of a .243 Winchester Or a 6mm Remington..
The .22/250 is a .300 Savage case necked down to .224-inches... and, as I already explained, the .243 case is a .308 Winchester (7.62mm NATO) necked down to .24 caliber. The "difference" in the powder capacity of the two cartridge cases is about 10%... with the powder capacity of the .243 Winchester cartridge being slighty greater, but NOT by MUCH... certainly not enough to be concerned about.
The .223 Remington (aka 5.56mm M-16 round) has a considerably SMALLER powder capacity than the other two previously-mentioned cartridge... more on the order of about HALF the powder capacity of the .22/250 OR either of the previously discussed .24 caliber rounds.
The little .223 firing a 50 grain bullet out of a 26-inch barrel will have a muzzle velocity of about 3400-3450 fps compared to a .22/250 firing the same bullet at about 3800-3900 fps depending on the powder used and the barrel length.
Moving up to a 55 grain bullet (the .22/250 factory ammo and handloader/shooter is more likely to use the 55 grain bullet), the smaller cased .223 Remington slows down to about 3300-3350 fps vs. the .22/250 which gets about 3675-3725 fps.
However, a .243 Win. or a 6mm Remington will put out a 70 grain bullet at approximately 3575-3640 fps (add 50 fps for the 6mm) that is NEAR the same velocity as a 20% lighter .224 bullet out of a .22/250
and the .24 caliber bullet will retain its velocity much better while bucking the wind better as well. And we havent even discuss killing power yet. Obviously, the .24 calibers are much superior to the .22 calibers.
If money is no REAL object, Id go with the Tikki with at least a 5x-16x scope in 6mm Remington with a 26-inch barrel. And if shooting ranges might reach out to 350 or even 400 yards, Id go with a 6x-24x scope.
If noise is a factor and shooting ranges wont exceed 250-275 yards, Id go with the Tikki in .223 caliber.
If money was somewhat of a factor, Id go with the Savage in 6mm Remington and still buy a reasonable good scope.
If money is a BIG factor, Id use the short barreled .243 by adding a good 5x-15x scope
OR
tune up the .270 Winchester and put a 6x-24x scope on it
it might surprise you if you do a good job of free-floating the barrel from the recoil lug forward
and make sure the action is well-seated in the stock and the trigger crisp and at less than 2 lbs. That short barrel on the .243 is losing you about 30-60 fps for every inch the barrel is shorter than 24-inches.
Of course, for best accuracy, youll have to handload for any of these rifles, but this would be especially important with the .270
plus if you do a lot of shooting with the .270, your shoulder is going to let you know it. The noise level is also going to be greater than with any of the other calibers, but you should be wearing very good hearing protection in ANY case with ANY of the rifles/calibers mentioned.
Theres a LOT of factors that can change what Ive written here
but a big one is that .24 caliber rifle could also serve as a fine, long ranged deer or antelope rifle
none of the .22 calibers could.
Good Hunting!
Strength & Honor,
Ron T.