the 600 came in 2 flavors. the original from 64-68 was a 18" carbine with a plastic ventilated rib and walnut stock and short action with a dogleg bolt. came in 222, 223, 243, 6mm 35 rem and 308. the 600 magnum was the same but came with a laminated beech/walnut stock and came in 350 rem mag and 6.5 rem mag. in the 70's they came out with a 600 mohawk that was pretty much the same but no vent rib and either walnut or hardwood stock. not sure of the cals but i know 222, 243, 6mm and 308 at least.
i have a '65 350 mag and can attest to the jawsmacking recoil. it is not a very pleasant gun to shoot and if you don't get a good cheek weld it will knock you a good one. but, it is big deer medicine. the deer that have walked in front of my 350 did not take another step.
a 600 in 243 would be a really nice little giun. good for kids, women or even 250 lb men. i want to get one in 243 one of these days.