Its unfortunate you got a bad barrel probly. Winchesters factory barrels are suppose to be junk. My 25-06 on the other hand has shot some really impressive groups. You would not expect it to come from a factory rifle, put it that way. With that said, you probly still have a lot more accurate/consistent rifle since it was rebarreled then you woulda got with a Kimber or Cooper. Thats just my opinion though. 3/8" with 40g's at 4400fps is quitea yote buster, but let me tell you that if you dont hit them square, you will have them running off. This is from experience. My 220 swift shoots one of my 40g Btip loads at 4400fps and they have knocked more than a few dead, but its got to be a solit hit is all I'm saying. The 55g at 3900fps is a lot better bullet for these size cases. Thats my favorite yote bullet out of my Swift anyways.