So here's a new one

[Etter]

So Ive been having a tough time tuning arrows to my new kanati but finally got a combo that was perfect. So I went to check them with broadheads and suddenly theyre showing weak (fletchings kick left, impact right). So I started cutting a hair off at a time thinking they were just showing a small error in tuning. I ended up cutting another 3/4" to get perfect broadhead flight.

I figured, fine. Now Im good. Until I screwed a field point back on and arrows show stiff again!  So Ive got perfect broadhead flight but cant shoot field points anymore. Broadheads are 1" longer than fp's but Ive never seen that matter before like this.

Anybody had this same experience?

[madmaxthc]

Are you confident the nocking point is in the right place? How does the nock sits on the string? Too tight/too loose?
Do you use a string that is done properly and does not stretch easily? I had all the above issues in the past, and couldn't spine the arrow properly till I solved them all.
P.S. Are you sure broadheads and field points are the same weight? Are the broadheads well made?

Hope it helps

[Etter]

Everything else is correct. I guess the extra inch of broadhead just makes them a bit weaker.  Same thing with zwickey deltas and vpa's. Ive owned 6 different trad bows and never saw this before. Oh well. Its worked out now.

[M60gunner]

Yes, but with carbon shafts. I cut as well but when I got done I was to short for broadheads. So... I got another doz. and started over. Carbons are a different critter at times. God forbid you change anything even nocks.

[jt85]

As I read this I couldn't help but wonder if adding an inch longer or shorter feather would help anything? I have no idea just curious

[Etter]

Im shooting 5" feathers with a strong helical. It just turns out I have about 10 arrows that are broadhead only. Maybe I can find some 2" long field points somewhere. I love how durable they are and my ability to build a bone breaking high foc arrow, but man are they frustrating at times!

[HMlongbow]

check your weight on arrows as I have arrow dynamics and had the same issue once I figured out they were 40-50 grains difference I sorted and now have broadhead arrows and field point arrows.  go figure

[longbow fanatic 1]

What I've found is that if you bare shaft tune with fletched field tips, broad head flight will usually group the same as field tips.

http://acsbows.com/bareshaftplaning.html

Read this and went and checked my cedar and Surewood tapered arrows, just the same.  I do have a couple of wide 160 grain vent heads that i do not trust in a strong wind.  They are good in a 15 mph cross wind, but with a strong quartering from the rear tail wind, a bit shifty in the air.   Aerodynamics can be peculiar when we least expect it.   I sometimes wonder if certain arrows may have a minimum stable air speed.  The local compound boys say that certain broad heads have a maximum air speed.