Under spined ?

[CaliforniaMuley209]

Im swithing to a heavier arrow this year and have decided to shoot 100 grain broadhead with a 50 grain insert. Shooting an Easton axis 300 spine arrow. I shoot a 30 inch arrow with a 70 lb Hoyt. Shoot be about 471 grains. I am kind of worried about being under spined but different charts say different things. What do you guys think ?

 

[dixon4420]

Should be just fine at that weight. Possible it was too stiff before adding the weight depending on speed and draw length, but should be fine either way

 

[jakelogsdon]

There are a few dynamic spine calculators on the Internet. I've used Archers Advantage on my laptop for many years. Its pretty basic but has some tools for building sight tapes as well. 30 inches is a fairly long arrow. I probably wouldn't go less than 300 spine. I have a 30" draw and all my arrows are cut at 29" doesn't sound like it makes sense. But it works. Length of arrow was important for me, to find that happy medium between weight to speed and also maintain good flight characteristics.

 

[Rob5589]

It may be right on the edge of underspined according to some calculators. Only way to know is to try. My guess is you'll be fine.

 

[Beendare]

Wouldn't hurt to bump up your spine.

I'm running the same arrow at 28 1/2".I think its 473gr with a 50 gr insert, 150gr BH......any longer and I would bump up spine.

 

[Billy Goat]

What is your draw length?

30" on 300 spine with 28" draw you should be fine. I think if your 29.5"+ draw your going to be on the weak side. Might work, might not. I haven't seen a disadvantage to being stiff shooting broadheads.

 

[CaliforniaMuley209]

My draw length is 29. So I’m right in the middle. Lol thanks for all the insight guys I appreciate it.

 

[CaliforniaMuley209]

What is your draw length?

30" on 300 spine with 28" draw you should be fine. I think if your 29.5"+ draw your going to be on the weak side. Might work, might not. I haven't seen a disadvantage to being stiff shooting broadheads.

^^

 

[Billy Goat]

^^

If your asking me I'd go higher spine. Some bows you can get by, others you can't. Stiffer spine speeds the broadhead tuning process.

I wouldn't run a .250 spine on a 50# bow. But @ 70# I haven't had an issue with overspined arrows except some double shafted arrows I built years ago. But they came in around .120 if I remember correctly.

 

[406unltd]

Should be fine but you will notice if it’s no good by how it shoots. You can then always cut some off the back end. At your DL most people run a 28” arrow

 

[Drew]

I just shot some 30.25” Axis 300 with a 50gr insert and 100gr field points at 70#. Bullet hole through paper and at 20 yards they are grouping good. Haven’t tried broadheads yet. They are 514gr with 4 fletch AAE. I want to get them a hair lighter so I’m going to try and work down to around 29.5” or to where they show sign of getting too stiff.

 

[Boharchery]

I would go to 250 if it were me, will make your arrow heavier also, a plus in my opinion