help with arrow spine

[Kas]

hoyt rx4 alpha
29" draw
87.5lbs
easton axis 5mm
or easton axis 4mm
arrow is at 27"
currently 340 spine and i know im too weak

am i really going to have to go to a 250 spine... or does such a short arrow get me closer to optimal spine stiffness

[jkelbe]

Also you need to consider your point weight, 100g, or 125g or 150g, extra insert weight

With 87 lb draw I thnk that is heavy, I would expect you to be at 250 spine. I am at 250 arrow spine with a 31" draw, 70lbs, 125g tip, 50g insert

[txbowman12]

Using archers advantage software (which maxes out at 80 lbs draw) and your specs. 5mm axis with 150 grains total point weight (including insert), is stlightly stiff with an FOC of 12.7%. At 87.5 lbs (my shoulder just tore typing that) you should be fine I think.

The 4mm axis match grade 250 are rated "too stiff" until you hit 250 grains in point weight. FOC of 20.8% and a 543gr arrow. Would be a hammer of an arrow.

Don't see how you could get 300 spine and I wouldn't shoot 340 at all

[enewman]

hoyt rx4 alpha
29" draw
87.5lbs
easton axis 5mm
or easton axis 4mm
arrow is at 27"
currently 340 spine and i know im too weak

am i really going to have to go to a 250 spine... or does such a short arrow get me closer to optimal spine stiffness

without more detail on what you are doing, but at what you are showing you need a 250 spine minimum.

[enewman]

Using archers advantage software (which maxes out at 80 lbs draw) and your specs. 5mm axis with 150 grains total point weight (including insert), is stlightly stiff with an FOC of 12.7%. At 87.5 lbs (my shoulder just tore typing that) you should be fine I think.

The 4mm axis match grade 250 are rated "too stiff" until you hit 250 grains in point weight. FOC of 20.8% and a 543gr arrow. Would be a hammer of an arrow.

Don't see how you could get 300 spine and I wouldn't shoot 340 at all

I ran the spec in q spine. used a standard 14gr insert and a 100gr broadhead. it shows an Ideal spine 273. so he needs a 250 spine. 125gr tip 266 spine.

250gr tip took it to a 237 so it would take a 200spine.

now the question is, which program is correct?

[Kas]

I ran the spec in q spine. used a standard 14gr insert and a 100gr broadhead. it shows an Ideal spine 273. so he needs a 250 spine. 125gr tip 266 spine.

250gr tip took it to a 237 so it would take a 200spine.

now the question is, which program is correct?

guess we will see... think ima go with axis 4mm... at 250 spine and hopefully find a bullethole...50 grain insert 100 grain head...15 grains fletching 6 grain nock... should put me at 438 grains...27" arrow..... but we shall see

[enewman]

I looked at sirius spine chart.

it only goes to 84lbs

100gr to 125gr tip 300spine
150gr to 175gr tip-250 spine
200gr tip 200 spine.

charts are just as good to look at. from this chart and based on 87.5lbs you need a 250 spine with no more than 175gr on the tip. even then I would look at 200 spine.

[enewman]

guess we will see... think ima go with axis 4mm... at 250 spine and hopefully find a bullethole...50 grain insert 100 grain head...15 grains fletching 6 grain nock... should put me at 438 grains...27" arrow..... but we shall see

just remember you can tune just about any spine on that bow. from that 350 spine to a 150 spine. In my opinion, go with a 250 spine tune the setup.

man are my eyes getting bad. I read your post and thought, why is he looking for a butthole. haha ****.

[txbowman12]

I ran the spec in q spine. used a standard 14gr insert and a 100gr broadhead. it shows an Ideal spine 273. so he needs a 250 spine. 125gr tip 266 spine.

250gr tip took it to a 237 so it would take a 200spine.

now the question is, which program is correct?

Probably yours, I've noticed before that when I change too much too quickly on AA it doesn't seem to capture all the changes.

[enewman]

Probably yours, I've noticed before that when I change too much too quickly on AA it doesn't seem to capture all the changes.

I have seen the same thing.

[wdtorque]

That's a lot of bow! ask Ranch Fairy :-)