# AMO questions

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How many grains per inch does AMO use??

What is the fastest bow with a draw weight of 80 pounds or less using AMO standards and a brace height of at least 7 inches??
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#### YRhinefield

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AMO is 9 grains per lb.

Most manufacturers only quote IBO speeds but generally speaking the fastest IBO rated bows will also have the fasted AMO speeds.

#### DB444

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How many grains per inch does AMO use??

What is the fastest bow with a draw weight of 80 pounds or less using AMO standards and a brace height of at least 7 inches??
Grains per pound not grains per inch--thanks for the clarification--I'm still half asleep.

#### IlBuckMaster

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AMO is 9 grains per lb.

Most manufacturers only quote IBO speeds but generally speaking the fastest IBO rated bows will also have the fasted AMO speeds.
It is not that simple. AMO calculates arrow weight by using a different set of assumptions from the IBO organization.

In IBO - they use 5 grains per pound regardless of cam type, draw weight or draw length. In AMO, the grains per pound will vary depending on cam type, draw weight and draw length (actually arrow length - but they assume the two are the same).

An example from the AMO charts:

A speed bow set at 70# draw weight with a 30" draw requires an arrow with a minimum weight of 487 grains (appr 7 gr / lb). A speed bow set at 70# draw weight with a 29" draw requires an arrow with a minimum weight of 454 grains (6.5 gr / lb).

IBO requires both bows to use a minimum arrow weight of 350 grains.

#### LFM

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The AMO is really no more it is now the ATA more of a Trade Organization that anything the AMO was. It has been that way for sometime. That is why many use the IBO Specs to come up with their speed etc on bows and such.

They really only do trade shows these days nothing more. I don't think they have any kind of engineering staff to continue these kind of things. That has been for sometime since the switch like 5 years now.

If you do a search for the amo you won't find much on them any more...

I had questions back then and looked to see what they had to say and got very little info back and it was suggested they are no longer what the AMO was but now Archery Trade Association. So it sounded to me that the amo is gone.

Just an observation.

LFM

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