Spine?

[isItFallYet]

28.5

 

[Brendan]

28.5

So, no reason to be running a 30" arrow. I'm a 29.25" draw, and run a 27.5" arrow. Cutting it shorter stiffens it up and allows you to get away with a softer spine.

But, with a Vertix at 70, 28.5 draw, 27.5" arrow , you're still trending weak with a 340 spine even if you run a 100 grain point and a 20 grain insert. You should probably be in a 300, and then can run it with 150 - 175 grains up front no problem.

 

[isItFallYet]

That’s not an option, unfortunately. But that also wasn’t my point.

 

[Brendan]

That’s not an option, unfortunately. But that also wasn’t my point.

Fact remains, you're weak with your setup and a 340 spine. Wrong arrow, and cut wrong to add to it.

I'd test fixed blades to see if you can get it to tune and get them flying with your field points. If not, you might have to make changes anyways.

 

[isItFallYet]

Fact remains, you're weak with your setup and a 340 spine. Wrong arrow, and cut wrong to add to it.

I'd test fixed blades to see if you can get it to tune and get them flying with your field points. If not, you might have to make changes anyways.

Explain what you mean by weak? I have been shooting broadheads and am shooting what I consider accurate to 80 yards. Also, why is it cut wrong? Cut wrong would depend on the rest that I'm using. It would be impossible to use a much shorter arrow unless I was using a different rest like an overdraw style rest.

 

[Brendan]

Explain what you mean by weak? I have been shooting broadheads and am shooting what I consider accurate to 80 yards. Also, why is it cut wrong? Cut wrong would depend on the rest that I'm using. It would be impossible to use a much shorter arrow unless I was using a different rest like an overdraw style rest.

First off - incorrect on the rest. Draw length measurement is the distance from the throat of the grip to your string plus 1.75". So, on a 28.5" draw length bow like you have, that distance is 26.75". So, you can run an arrow 1.75" shorter than your draw length, and have the front of the shaft be around the Berger Hole. You said you're running a 30" arrow, and a 28.5" draw length. I personally would probably be running a 27" arrow carbon to carbon with your setup, as it stiffens the arrow, and allows you to run heavier broadheads and inserts for easier tuning, more forgiving flight, and better penetration. (Lighten the arrow, more weight up front, higher FOC). Comparision point - I have a Triax with a QAD rest pretty close to the riser - i.e. not any strange overdraw setup. Bow is 29.25" draw, arrow is 27.5" carbon to carbon, and I (barely) have room for an Iron Will Collar on my arrow still clearing the rest.

What I mean by weak is if you put all your numbers into an actual spine calculator instead of looking at a generic chart, assume you're running 100 grain broadhead and a 20 grain insert which is about as low as you can go, assume you're running heavier fletchings and a wrap, and you're to the weak side of ideal but probably fine. It might tune fine, but that depends on the exact components you're running. Add a 125 grain point, heavier insert, no wrap, lighter / smaller fletchings and it starts to get worse.

Do your field points and fixed blade broadheads hit at the same point of impact at 80 yards, except for maybe a little vertical difference? If so - you're fine. If not, bow isn't completely tuned and arrow isn't leaving the bow true.

Again - all of this is just advice. Take it or leave it, but I think you have a lot of room to improve your setup, and you were bringing up spine, spine charts, etc.