Ok, help me diagnose this. First, this is another spare bow, I decided to work on just for experience and playing around. PSE Mohave with medium Synergy 3 cams. Wieght set to 69#. Draw set to 29.5". New cables and string. Cam timing seems perfect. 1st gen MZE rest. 42" ATA Around 7" BH. 100gr tips.

I always shot Beman hawks 400 cut at 29" with this bow. Worked thru several interference issues. Always getting a left tear (fletch to the right, tip to the left) and bad groups.You can move the rest all teh way left or right and same thing. Tells me interference.One my MZE wasnt' dropping as fast as needed (about 4-5" from full draw). So I set it up to drop within 1.5" of full draw. Helped alot. Found out my cables were close, but should have cleared them by eyeballing. Moved them over. Still can't get the 400 hawks to get perfect tear or group. Always left tear (fletch to the right, tip to the left). But only slightly, maybe 5/8" tear now.

So I tried a few more combos, and found .340 spined black max shot bullet holes. So did .350 carbon express CX. Groups pretty awesome for a spare bow. This is kinda nice cause this is for my main compound. But I want to know why. But from history of this PSE, this makes no sense. The .400 spined hawks should work, it used too years ago. Also, all charts, show .340 black max to be too much spine. And the .350" even more way too much spine. I bet I shot the .340" spined arrows 10 times and awesome bullet holes.

So why would a stiffer arrow work better when its not supposed too and never did before. All I can think of is the cables and new string are 450+.

Tonight I will drop poundage to 65 or so, and check again.

This is just playing for a spare bow. But for my info, would like to diagnose the issue. This tear is always tough to fix. And would like to understand it better.

Looks to me like you've already diagnosed the problem and have the solution. Remember that arrow charts are only general guidelines and cannot account for all the variables, like different string/cable materials.

Your bow setup always has the final word. Shoot what it likes and it'll be happy.

I think I am there. But hate these pesky tears like this. I have MZE on two bows. And plan on my next bow not having it. I always like it for boar hunting, but that about it.

I will play around tonight with poundage. One theory I thought about is the weaker spined is still in archers paradox or still bending and causing interferrence by the tail slapping around?

You should be able to move closer or farther from the paper to determine something like that, shouldn't you?

No, I was meaning the tail is flipping with the weaker spine and touching the cables or the riser. I know some like to use powder footspray.

I'd say drop the poundage 10 lbs. and try again with the 400's. If they work then, you know it's a spine issue with the arrows. At 70 lbs. and 29" the 340 or 350 deflection rating sounds more like what I'd have chosen. I'm surprised to hear the 400's ever shot well (is the spine shot out of them?).

This is another thing I was thinking but thought it might be a stupid idea. These arrows are pretty old, about 8 years or so. Shot alot. Who knows how many times. I mean I found blood and hair on one from years ago. I hear about spine changing over time. Wished i had a ram spine tester or something like it.

As I was reading your post that is the first thing I thought, bad spine. That or very poor grip.

When drastic changes to the rest yeild little or no result I always start to quetion spine as the culprit.

Paul

If Alaska is right, then tonight I should see an improvement with 6lb drop in wieght.

Thanks, guys for the advise.

A 29 inch 400 spine arrow is going to take between 55 and 60 pounds max draw weight , with 100 grain heads , you were way underspined .