carbon/POC spine

[hogdaddy]

while i haven't made a POC arrow in years I got roped into making a dozen for a friend. My question is what spine POC shaft duplicates a 400 spine carbon shaft?

A very enthusiastic young lady at 3rivers did a long calculation and came up with POC 80-85 spine = 400 carbon spine, having trouble digesting that and thought i'd check here.

[Bisch]

carbon/POC spine

I have a chart that says .400 spine is the same as 65#.

Not sure how accurate it is, as I got it off the internet a while back.

It’s hard to campare carbons to woods though. If he is shooting 50# and has a lot of weight up front, you just can’t take a wood shaft of the same stiffness and replace it. The only way to know for sure would be to get a test kit or something with different spines, and figure out what weight is going on the front, and then do some tuning to see which works best!

Bisch


Sent from my iPhone using Tapatalk Pro

[Wudstix]

I've had good luck shooting Beman ICS 400 from my 60-65# bows with lighter heads/field points 125-145 grain.

[KenWood]

I shoot 400 carbons 31.5” with 250 grains up front. Same bow 70-75 woods full length with 160 grains up front. Maybe that’s a start.

[RickBarbee]

All carbons are factory spine deflection measured on the ASTM scale, which is 1.94# on a 28" span.

The old AMO standard is spine deflection measurement with 2# on a 26" span

An ASTM .400 is the same as an AMO .330

An ASTM .400 shaft has an actual static spine of 78.8#

An AMO .330 shaft has an actual static spine of 78.8#

In other words - 78.8# is what you are looking for.

Rick

[RickBarbee]

I should add:

The POC wood shafts are likely going to be larger in diameter, than the carbons. Probably quite a bit larger, so that needs to be taken into account when trying to match woods up to shoot the same from the same bow as the carbons do.

The larger the diameter, the farther outside center the arrow will rest, therefore the weaker the spine they will need to be.

If I knew what diameter the woods are, I could figure what spine they need to be to match the carbons.

Rick

[hogdaddy]

Thanks everyone, i shouldn't agree to do things when drinking whiskey but i did.
he's never shot trad, wanted one that I made just because... and had money so here i am.
(my shoulders wore out in about 2005, have shot compound since then) so there sits a seriously dusty shop frozen in time. going to make one last dozen.

The bow is a LH sinew backed osage recurve probably 50 lb.s now used to be more when made in EL Paso probably 20 yr's ago. He bought carbon 400's cut 28 in. 125 points, doubt if he's pulling an honest 24 in. (over bowed)

shot it yesterday with POC 23/64 60/65's 28in. seems right at 28 DL, stiff when short stroked. Going with 60/65 rose city tapered POC leave them long, take some bare shafts, taper tool and different weight points i guess.

On a side note I never stoped making arrows just dip, crest burn feathers etc. on carbons nowadays one of the few things you can do to make a compound "yours". kind of neat to do woods again.

[Bisch]

Good luck with those sticks!!!

Btw, that’s a heck of a warthog in your avatar pic!!!!

Bisch


Sent from my iPhone using Tapatalk Pro

[Bisch]

carbon/POC spine

Just an observation, but a .400 spine arrow cut to 28”, without a crapload of weight up front (like probably 300gr or more) is gonna be waaaaaay too stiff for just about any 50# selfbow (much less one he’s only drawing 24-25”)!!!!!

Bisch


Sent from my iPhone using Tapatalk Pro

[RickBarbee]

Sorry if I was misleading.

That said - the information I gave was all correct.

My obvious mistake was in assuming the .400"s were a good match up, and shooting good from the bow. Things like that happen when you don't have all the info.

Rick