BigJ71

I have just bought some carbon arrows for hunting and I am not sure if they are the correct weight and spline for my set up (first carbons). I hope someone can help.

Bow: 70lb pull, 32.5in draw, speed cams, 8in brace height , 2 tie on nocks and string loop, surz peep and 2 cat wisker silencers

Arrows: 6075 12.7 grn per inch x 33in = 419.1grn
Broadhead: 100grn
Nock: 13grn
Fletchings (3 4in vains) 7.4 x 3 = 22.2

Total Arrow Weight = 554.3grn
Total Arrow Length (including broad head) 34 3/4in

First, Is my arrow weight calculation correct?
Second, is this too much or not enough for my set up? this comes out to 7.9 grn per lb. Is that ok?

Maybe I should have stuck with aluminums this is complicated!!

Any suggestions or comments would be great.

Thanks

hunter9022

That sounds like its fine. What type of arrow are they? I cant tell by the spine if they're gold tips or Carbon Express. You have enough weight if thats what you're worried about. The only real concern is with that long of an arrow, the spine tends to weaken a little, but that still doesnt even to be a problem with what im seein. As long as theyre grouping right and tuning right, you dont have to worry about it.

Dairy King

7.9 will work for hunting, perfect, really. but if your wanted something for 3d or target, its a little heavy by most peoples standards. With your poundage and draw length, I wouldnt worry about it, your arrow is FLYING im sure.

BigJ71

Thanks for the replies....

They are carbon express arrows, and I just hunt no 3D.

That arrow length is about as short as I like to go. With that length it puts the broad head just past the riser. I have the bow set at 32.5 but the arrow insert is right inline with the front end of the riser and the arrows are 33in exactly.

With the string loop pulling the string back even (no nock tilt) that would make the draw 33in...... I should measure.

The bow is from 31-33 but like I said I have it set at 32.5. Perhaps it's actual length differs slightly with the "set length"

I'm no speed freak I just hope with that arrow weight it's fast enough, (554.3grn seems like a lot to me) I don't know, I have yet to shoot the carbon arrows to see how they compare to the aluminums.

buckeye

BigJ12

You forgot to add in your insert weight.

JoshKeller

With arrows that long, you'd better be dang sure you're checking them after every shot for cracks and splinters.

And if you notice your groups starting to grow larger, its most likely the spine is weakening, which seems to happen alot faster with longer arrows. I'm currently shooting 30.5" arrows, and I have to replace them much more than my friend who shoots 25" arrows.

BigJ71

Josh, is that 30.5 including the broadhead? Also the weakening spine theory is the main reason why I went with such a heavier grn per inch, 12.7. Now I'm wondering if it is too much?

Does anyone know approx. what kind of speed these arrows will produce out of my set up?

I never really thought about it (weight) when I was shooting the aluminum arrows, I would like to think the carbons would be faster? my aluminum arrows were Easton GameGetter II 2219 everything else is the same.

Thanks

JoshKeller

No, I'm shooting 30.5" arrows from nock groove to insert. Shooting 70 lbs, at 32.5" of draw will give you enough speed, so dont worry about that.

BigJ71

Thanks Josh

MO_Bowhnter

Try bowjackson.com

This website has a arrow weight calculator which factors in every part of your arrow.