wilderness guy- what KIND of game are you going after?- what the shoot back east goes away different from what we get in the rockies-
you CAN shoot 223 in 5.56, but not necessarily the other way round- has to do with the leade( not a spelling mistake- the word exists) and the barrel twist- you really can't go wrong with a 308, but 7.62 is EXTREMELY hard to come by surplus- i've seen it run as high as commercial at gun shows- the 308/150 is pretty tame as loads go, and will do most of everythiing"back east"- but you have to check your regulations on the use of fmj bullets- in the alberta manual it says/used to say"the use of non-expanding projectiles is expressly forbidden"- that is/was right out of the regs- blasted sabre says they're legal in ont- we also used to have a reg that said the cartridge had to be over 2 inches in length - that let out a good deal of chamberings, but i know that one was repealed
as far as making a soft point out of an fmj, DON'T DO IT- if you drill, file or grind that jacket down or off, what happens is you disturb the integrity of the jacket, and the bullet can and does shed the jacket from time to time-