More people have quit archery over papertuning than any other reason...........it plain sucks! If you don't like the tear move back or forward 3 more feet and you will have a different tear! I use the walkback method with my broadheads. I start with field tips at 20 yards and move my sight to where I am hitting a 2 inch bullseye with every arrow (if you have 1 or 2 arrows that are out of the group rotate the nock 120 degrees until it hits with the rest of them. Once you have done that....sometime this takes hours to get 6 arrows to hit the same spot. Once that is done shoot a broadhead @ 20 yards and see where it hits (I only shoot 1 BH at a time and then pull...I get SICK of refletching arrows!
Now the BH will most likely hit a wee bit off from the field tips...it is a RARE bow that will put field tips and BH in the same hole at 20 yards. Now...if for example the BH is 3 inches low and right of the FT, every so slightly move your arrow rest to the left and move your sight down just a hair until you hit center with the BH....
Once you have that done do NOT adjust your sight housing anymore...Now make sure that all your BH's hit the center @ 20 yards...you will have to do alot of nock rotating to get say 4-5 that will be darts for you. (out of a dozen arrows I usually only get 4-6 that are up to my accuracy standards for BH..but I am VERy picky when it comes to this.
Now move to 30 yards and use your 20 yard pin...your arrows will obviously hit low, but that is OK. Most likely your arrows are going to be left or right of the center....now it is just a matter of very small adjustments R or L to your arrow rest. Move the rest in the opposite direction...IE, arrows are hitting right of center, move the rest left..very small adjustments are key here....
Then do the same @ 40 yards again using your 20 yard pin...once you have all your BH's hitting center your centershot is now set...crank your rest down so it will not move...now go back and sight in your pins for those distances......works like a champ and has never failed me....I can put all of my BH in a two inch bullseye at 50 yards...if you need anything else....just ask! Like some of the others mentioned, make sure your grip is loose and consistant...very critical for BH flight...and make sure your anchor point is not floating around...I have 3 references for my anchor point, my peep, my kisser button and my nose on the string, if you don't have 3 points to keep you consistant...your gonna have issues.....Take it from an archery coach!
Tim