When I first had my FGW open gun built, I had a slot cut for holes but none were drilled. I started with 124s, as I was just learning the game and wanted to play it safe. The first time I tried 115s was a game changer. I had to send the gun back to Bobby for some repairs and had him drill 2 1/8" holed while it was there. I adjusted my 115 load back up to a 175PF ( only lost about 20fps with the holes) and the dot tracking was perfect. It always went straight up and returned to center....it just seemed to happen a LOT faster with the holes. When I have another gun built, I'm going to experiment with v4 holes in addition to some straight up....I love the concussion