Can someone explain this POI?

Pydpiper · 01-04-2007, 03:32 PM

I bought 6 2216's to try out, fletched them with 4" Duravanes.
My goal was the line of electrical tape, distance is 20 yards.
Lower three arrows are GT II, brass inserts same vanes 435gr
Upper arrows are the new 2216's 430gr

Second photo is the same configuration at 50 yards, this time there are two 2216's with 2" vanes, consistant with the 4" vanes. After repeating this shot enough times to convince myself that it was not user error I realized my scope had somehow jumped out 1.5 inches (the bolts were off 3 inches @ 20 yards regardless), I corrected it and all is well again, besides these 2216's being so far off target, any thoughts?

Dnk · 01-04-2007, 04:32 PM

So the problem is the 3" of horizontal variance?

lemoyne · 01-04-2007, 05:13 PM

Just on a wild guess I would say you are using those moon nocks and some are just a bit out of line.
A suggestion get a few nocks from 10pt or excaliber and compare with some on each type of arrow. Lee

Pydpiper · 01-04-2007, 05:28 PM

Yes, the problem is the three inches, more important the fact that it isthree inches at twenty yards.

No moon nocks, these are out of the Excalibur box, the nocks are the same aluminum ones I use on the GT II's Also, this is consistent out like this, these are a fine example, but each and every aluminum one does it.

Doegirl75 · 01-04-2007, 05:40 PM

I'm going to take a wild stab and say the brass inserts in the carbon bolts increases front of center. There might not be that much weight difference between the carbon and aluminum. But there is a difference in how that weight is distributed and I'm sure that's got to impact how the arrow flies.

Pydpiper · 01-04-2007, 05:48 PM

That was my initial thought as well Doegirl, but I think the arrow is moving so quickly in the first 20 yards that it hasn't had a chance to decide which part of it was heaviest, maybe out a bit farther though, 40 or 50 yards..
Also, if a weight issue wasraising that arrow that far at 20 it would be off the charts at 50..

Dnk · 01-04-2007, 06:01 PM

I am going to guess at spine.

Pydpiper · 01-04-2007, 06:20 PM

DNK, can you elaborate a bit? I don't understand, what spine?

shewe · 01-04-2007, 06:24 PM

foc should'nt be that drastic. my first thought like don's is spine.[8D]

awshucks · 01-04-2007, 06:28 PM

I love a good mystery, especially when it's someone else's! lol. Lemme take a guess. Even though the two arrows weigh close to the same, the GT's have brass inserts and the aluminums have aluminum insert?? If so, riddle solved. david, check the foc on both and let us know, quicky way is 5% for every inch between 10" and balance point. I didn't think of this earlier when you pm'ed me.