First off , I know verry little about pressure. I am currently waiting on a 260 rem from Cooper . The rifle is offered in 1 in 9 twist rate, it would cost me 440$ to change the twist rate to 1 in 8 to stabilize a bigger bullet better. I will be reloading 140 grain lapua's and Berger's starting out. Cooper says that they reach the accuracy gaurentee with 142 gr sierra's just fine. So im going with the 1 in 9. I am assuming that a 1 in 8 would give higher pressures????? When i start working my way up to a max load what is usually the first signs of pressure? the gun will have a 26 inch barrel. The longer the barrrel the higher the pressure? I have never had pressure issues as I always have just realoaded for the 243 out of the mannaul.