Actually the weight of the bullet has nothing to do with the twist require to stablize it, it is the lenth of the bullet. If we are talking about bullets of the same material then the heaver the bullet the longer it would be, but if you compair a 40 gr. copper bullet to a 50 gr. lead bullet the 40 gr. bullet will be longer. The longer the bullet the faster it must spin to be stablized. The 1 in 14 twist in .22 cal. is great for the liter bullets, up to about 55 gr. where it starts to get shakey. If you go to the heavy end of the .22`s like the 80 gr. Sierra and Bergers you need a 1 in 8 twist to stablize them and if you want to try the 90 gr. Bergers they say you need a 1 in 7 twist. If you want a quick lesson and ready refference go to
www.bergerbullets.com. They give the recomanded twist rate for all of their bullets.