hello I presume this has been hashed over so many times but evidently its still a hot topic.. I just put together a 7mm BR rifle with a 1-9 twist Wilson SS 26" #4 contour barrel and is topped off with a new 6-25x50 CV life scope w/sunscreen My bullets of choice is the 100gr HP sierra and 110gr speer hp and the 115gr speer hp and the sierra 120gr sp and the speer 130gr spbt ..and speer 145gr spbt .without a chronograph my velocity's are a guesstemate at 2800fps for the 100, 110, 115, and 2700fps for the 120gr and 130gr... so I have been told that my twist rate is too fast.. so I found a site on the web that calculates twist rate based on the bullet design and length and lo and behold if all I wanted to shoot 100grners a 1-16 is good to go. move to the 110 and it shrinks to 1-15.. 120gr takes it to 1-15 twist ...130grners went to 1-14. 145grners went to 1-12.75 twist.... (i imagine 1-12 would suffice) So overall a 1-12 twist it would seem is what I need as I won't shoot anything heavier than 145gr. has anybody else ran across this para-dime? and if I do shoot this one-in nine twist tube,when will bullet RPM's be so great as to grenade the bullet? or is that so far of velocity wise I dont need to worry about that? or will full power loads overcome any shortfall in the chamber and fly straight? Or should I start saving money right now and upgrade to the 1-12 barrel? the whole reason why I went to the 7MM BR was to shoot light loads in the first place.