gutshot

I was wondering what the number designation on carbon means. I know what it meanson aluminium but not carb.

bowtech die hard

most carbons have different charts and show what the designated # means. The best way to find out what spine the arrow is, is to check the chart online.

Trembow

The numbers are not really an industry standard, but you generally find one of these three:

1. The number is directly derived from the spine deflection rating for that shaft, such as on Carbon Express, Beman or Easton carbon shafts:

400 = ~ .400" deflection (less stiff)
350 = ~ .351" deflection
340 = ~ .339" deflection (more stiff)

In this case, a higher number means a "weaker" or "less stiff shaft"

2. The number is derived from the stiffness of the arrow such as PSE Carbon Force arrows:

100 = weakest / lightest shaft
400 = stiffest /heaviest shaft

3. Some mfrs simply give you a number that is a relative guide for what poundage bows the shafts are appropriate for. Such as Gold Tip shafts:

3555 or 35/55 = lighter/weaker arrow for bows between 35 and 55 pounds
5575 or 55/75 = heavier/stiffer arrow for "" "" "" 55 and 75 pounds
6595 or 65/95 = heaviest/stiffest... etc..

Tarheel_Hunter

There are no stupid questions....only stupid people.
JUST KIDDING! Wasn't that line in a Nat'l Lampoon Family Vacation movie?
Anyway, just thought I'd make an attempt at some levity there. Yea, I know....pretty lame.
By the way, as I understand it (and have read above), the lower the number on the arrow (at least on Eastons, Bemans, etc.) the "stiffer" and/or "heavier" the arrow.
I used to shoot 400's w/my Matthews FX. Then I went to 300's w/my Switchback (mostly because I was hunting boars).
Now me and my Tribute shoot Easton ST 340's. Seem to be a nice balance between speed and punch!
Good luck!