Unless you draw more than 29 or 30 inches, or shoot an extremely short recurve, you'll probably never encounter stack. What is it? Say a bow's poundage increases 2 pounds per each inch it's drawn, then at some point the pounds per inch increase suddenly jumps to 4 pounds per inch. That's stack. You would think that someone drawing well into the stack will get a super fast arrow. Not so. That bow will only shoot an arrow slightly faster than it would if it were shot at the draw length just before the stack point was reached. If the bow drew up to 45 pounds before it began stacking, it would perform pretty much like a 45 pound bow, no matter how far into the stack it was pulled, or how many pounds it drew at the stack. In other words, it wouldn't shoot hardly any faster at 60 pounds on a 32" draw than it would for someone shooting the same arrow at 28" draw and 45 pounds. The long draw guy just gets to pull a lot more weight with very little gain for his effort.
Most 60-62" long recurves I've shot didn't really begin stacking until about 30" draw - some at 29" - but, with my draw length, I've encountered a boatload of stack-a-matics over the years.[&:] That's exactly why I've gone to the custom bow market. The best factory bows I've encountered about not stacking too badly have been from Bear. Worst have been from Martin.
I like the explanation of cast I found in an old book, "Archery, From Golds to Big Game" by Kieth Schuyler:
Quote:
Cast, then, has come to mean in a bow: A combination of structural coefficients which permits utilization of the resilient power in any given material or materials.
The key word is utilization. For, without proper cast, power is wasted. Unless the bow is so constructed that it's power can be properly transferred to the string, utilized, it will shoot much more poorly than one of far less weight. A bow with good cast would permit maximum utilization of the potential power built into it.
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A bow that stacks has a large percentage of it's power built into the last few inches of draw. Almost all the power is expended in those few inches on the release. It slaps the arrow out of the bow. ... The bow has poor cast. Contrariwise, a bow with good cast builds up power gradually on the draw so that the increase is almost imperceptible to the archer. On release, the energy is imparted over a longer span of string travel so that the arrow slips away smoothly as soon as it's velocity overcomes that of the string.
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So, stack and cast are kinda interrelated. I also feel that a bow with good cast is also one that doesn't give you much handshock.
Some terms I don't understand
