Beman MFX tuning

[Ryan D]

Hey Everyone,

I am currently shooting ICS 500's out of my 50# at 28" bow with 100 gr inserts and 125 grain tip cut to 29" and they are flying great.  I decided to try some MFX's so I put the 100 grain inserts and cut them to 29" (not sure if I should have done this) but this is where I want to arrow length to be.  
I am trying to bare shaft tune them right now and they are hitting nock way high when they hit the target. My left and right looks good.  I have adjusted the nock down and it doesn't really help.  My brace height is at 7 1/2".  I am really confused or is this not something to worry about.  I am asuming that I am spined correctly but I can't make the up and down go away.  I have searched alot of other posts and haven't really come up with much. Thanks again guys.

Ryan  

[Ryan D]

Also I stepped back to 20 yards and it seems that my arrows are hitting left and nock left.  I am a left handed shooter and does this indicate weak spine.  I am confused because the ICS 500's shoot good.  Thanks again

Ryan

[katman]

You may try raising the nock point, sometimes to low will kick off the shelf. Get the porpoising out first then go with spine tuning.

'it seems that my arrows are hitting left and nock left' If you are shooting bareshaft and fletched you should know if the bareshafts are hitting left (weak for a lefty) of the fletched shafts. You can also go back to 25 yds if you can group from there. Some tune by watching the bareshaft but my eye is not good enough for that so I use OL's method of bareshaft tuning  http://www.bowmaker.net/index2.htm

[katman]

Also the small beaman will be closer to center shot than a larger diameter shaft and that effects spine.

[Ryan D]

I have just tried nock up and down and neither has that much effect on the up and down impact.  I guess my question now is do I start cutting the arrow down a little at a time to see if that will stiffen the arrow up?  Thanks for your help.  I am also not up to speed but how does centershot affect spine?

[soaring eagle]

the closer you get to center the stiffer the arrow needs to be.I would try some lighter points before I cut them. I shoot 400's 29" to back of point with regular insert and a 125 out of 52# bow