I had a rem m700 adl in .223 with that 1 in 12 twist, never could understand why remington would use such a loose twist for the .223, anyway the rifle would print decent groups with 55 grain bullets and would shoot better with lighter bullets I found the rifle to shoot 45 to 50 grain bullets the best. When I got into reloading I played with many different bullet styles and weights and found that with the 1 in 12 twist the heavier the bullet the faster you needed to push it to keep decent accuracy I tried a couple different 60 grain pills which did fine at 100 yards and found i was pushing closer and closer to maximum charges to sustain accepatable accuracy. feeling confident with a 60 grain v-max bullet with that twist rate to 100 yards I started to shoot the load at 200 yards and this is where i began to run into some seriously poor accuracy my groups openned up from 1 inch to 3 inches and at 300 yards it openned up to 6 inches and at 400 yards it was pointless wasnt even hitting paper consistantly and if i did hit paper it was a key hole. I eneded up trading that rifle to a buddy straight up for a savage model 10 in .223 which has a 1 in 9 twist it doesnt do very good with bullets lighter then 50 grains but with a 60 grain v-max the accuracy is phenominal I will post a pic of a 200 yard 10 shot group.