I have been loading for my 7 mm STW for about 2 years now and have had decent success with the 140 accubond, 140 tsx and the 160 accubond. All around 3/4". The 160's the first time out i used 79grains of H-1000 and got the gun to group under 1/4" at 3212 fps I thought finally found my load. Went home loaded up 20 not changing a thing. The last to times i have gone out to check zero for a trip and could do any better than a hair over 3/4" I havent changed anything i am aware of. What the heck am i doing wrong?