.223

220 Swift. Good luck.

for varmints , i have a .22 hornet , and a .22-250 , and i would recommend the .223 for you from those choices you asked about , the ammunition is cheaper , and it' s still very accurate out to 300 yards , which is about as far as the normal person should be shooting. the 2 inches extra of barrel will increase your feet per second or ( fps ) for short , but the biggest thing about accuracy that i know of is barrel weight and design. for stiffness and rigidness , the barrel would also be even better if it had been fluted too help in cooling the barrel down. the action is also important for accuracy , and the bolt to barrel lock up

I would go with the 22/250¬

All 3 are good choices. Personally I have a .22-250. I have a Rem 700 Varmint (stainless/synthetic/fluted) and it is a fantastic rifle. I' ve killed groundhog' s over 500 numerous times. It is extremely accurate...right out of the box. Amazingly...I haven' t been able to find a handload that will outshoot factory Hornady Varmint Express 55gr. 1/4" 5 shot groups with factory loads. The only thing I ever did...was lighten the trigger and top it with a Leupold. A buddy of mine saw how mine shot...so he bought the same gun. His shoots great too.

If you are going to get a Remington...I' d take a look at that one (in whatever cal you decide)