bfisher and AMO. Funny how the AMO (now ATA) can have stats showing proper arrows (which comes out heavier than IBO) and bow manufacturers having warranty of 5 grs per pound of draw weight. Of course Hoyt threw in it's two cents last year with their own ATA version of IBO.
One more advantage to using a heavier arrow, for hunting at least, is the additional momentum gained that translates into greater penetration potential when the arrow hits the game animal. You're chances of getting deeper penetration or a pass-through is increased with a heavier arrow and more so when you combine that with higher FOC. For anyone who wants to learn more on these topics and his extensive broadhead testing I highly recommend reading the Dr Ed Ashby field test reports. They are available here (http://tradgang.com/noncgi/ultimateb...ubb=forum;f=24) and here (http://www.alaskabowhunting.com/Dr.-Ed-Ashby-W26.aspx). Some very enlightening info he has amassed over his 27 years of study.
2008 Martin Firecat Pro-X (29" DL, 66# DW), home-made TRG, new VEMs, DS Advantage/HHA Pro-5519 front sight, No-Peep Sight Eliminator, Limb-Driver arrow rest, B-Stinger stabilizer/dampener, custom upper STS, G5 Head-Loc quiver on custom mounting bracket. Gold Tip Velocity XT300 arrows with Bi-Delta 2.5" Sharkstooth vanes and Grizzly single-bevel broadheads, 498 grains at 262 fps (22% FOC)
Now looking at the short draw archer, say 27" and the same 70# the AMO recommends a 388 grain arrow; still heavier than IBO but in the same proportion to the stored energy in the bow as compared to the 30" model.
So where am I going with this? Simply that the AMO found that they consider to be a safe minimum arrow weight for a certain draw length, draw weight and cam style and make recommendatons in proportion to the stored energy in the bow instead of having some RULE that is supposed to fit all shooters. Man talk about leveling the playing field for 3D????? It'd probably make bow manufacturers more happy, too, as they'd be replacing less limbs and other parts due to shooting arrows too light for the energy being produced.
I'm well aware that some of the lighter arrows seen at short draws and low draw weight would not be suitable for hunting. I'm just suggesting that there are other ways of thinking about the issue of minimum arrow weight other than just taking somebody's word for everything. Hey, if we didn't have a free thinking society we might still be using clubs and rocks to hunt with.
Martin/Rytera Staff Shooter
PSAA Life member, UBP Life member
PADI AOW Diver
Yes, bfisher, I saw the AMO charts some years back. And years back I responded to a magazine article about speed bows. The article covered most of the speedster and using 5 grs of arrow weight per pound. Back then, if I remember correctly, some or even most bows fell under AMO warranty claims. Evidently, I must have struck pretty close to home as my response about warranty claims was printed in a later issue. There were no disclaimers of my response.