Here are a few things to try if your arrow is fishtailing.
Check to see if bow is in tune and properly timed.
Always shoot it with the Coc$ vain in the up position with a drop away rest.
Punching the trigger will nearly always cause the arrow to fish tale. As will holding your bow differently.
Shooting in wind will make your arrow fishtail also.
And last thing I would test would be Arrow spine.
If your arrows dynamic spines are not lined up perfectly you can have some of your arrows fishtail and others shoot perfect.
I believe if you are shooting close to 70lbs with your bow you have too weak of a spine. You need to go to the 7595.
Here is how you check for weak spine. Shoot it through paper if you get a left tare that you cant get rid of it is too weak. If you can get your arrow to get a perfect bullet hole then follow these procedures.
This is the process I go through to get the Dynamic spines to match up.
Shoot one arrow through paper. If you get a bullet hole check it a different yardages to make sure it is still getting a bullet hole. All of my arrows will get a bullet hole at what ever distance I shoot at from 3 yards to 20 yards. Once I get an arrow to make a bullet hole I try another. If it doesn't get a bullet hole I rotate the nock and watch the tear move until it is perfect or close to perfect. I like to do this without fletchings, and then fletch them when all of the spines are matched up. If you have good form, and are not punching the trigger, and have the rest timed to drop out of the way quick enough for fletching clearance you will have the best groups you have ever shot. Here is a picture of 2006 Vegas 3d flights were I took first and won $500 bucks using these techniques. Hope they can help you out. If you have any questions just pm me! I am the one on the left side kneeling down.
