I just picked up a used Winchester model 70 in .270. Much to my delight it shot several different groups of .75"s. Since I don't have a varmint rifle that I can count on yet, I was thinking about using 90, 100, or 110 grain bullets for it. My friend told me that the 90 grainers wouldn't be very accurate and they would also wear out the barrel quicker than 130s or 150s. Is this true, or is he just repeating old wife's tales? The place where I varmint hunt has hundreds of ground squirrels and I usually move from place to place with my CZ-452 but I'm thinking it might be fun for some long range shots. Any advice, suggestions, etc will certainly be welcome!