Originally Posted by
dylan_b
the dollar bill thing isnt enough in most cases. about 2 years ago i was able to watch some testing being conducted on barrel harmonics and some interesting things came up in the slow motion video. to make a long story short, barrels vibrate ALOT more then most think and for thinner contoured barrels 1/16 to 1/8 clearance is needed depending on the caliber. and supporting the barrel does reduce the distance in the nodes of the vibration wave but it will increase the frequency so there is a chance that a load that might have worked in your gun might not be the most accurate anymore
You have to love high speed video. I'm sure that it was a thinner than normal barrel, but I saw a video once that actually showed a bulge moving down the barrel with the bullet. To answer the original question, try different ammo. I know that it's said all the time, but a lot of guys are hung up on really wanting to make a certain bullet work. My 700 in 30-06 really likes the plain jane 150grain Core-lokts, it'll group under an inch with them but Winchester 150 grain power points average 3" groups.