Short Versus Long

It's shorter! It's faster! It doesn't shoot worth a hoot!

I'm sure you have seen that advertisement. Wait, I think they forgot the last part. Of course they did!

Seems that's all some manufacturers can say are those two things. But they never tell you about how hard or 'unforgiving' these bows are to shoot.

So what makes a particular bow design more or less forgiving? Well, three major things:

Axle to axle length

Riser design, length/geometry

And brace height

All a person has to do is look at a bow to know if it's forgiving. A forgiving bow is a bow who's design inherently minimizes any mistakes made by the shooter. An unforgiving bow can magnify the mistakes  even to the point where it becomes almost inposible for an average shooter to group shots with it.

ATA(Axle-To-Axle) Length

If you were to try walking on top of a narrow wall, would you grab a short or a long pole to help balance yourself? A long one of course! It would be more resistant to any movement and help steady yourself. Same thing with a bow. The longer the distance between axles the more stable a bow is. What is short? 35 inches or less. A mid length is 36-38 and long is 39+.

Riser

There are two major things that affect riser design: length and geometry. A bow can have a longer ATA  but if most of its length is from long, lightweight limbs it still may not be as forgiving as another bow with the same ATA but with a longer, heavier riser and short limbs. A longer riser puts more wight at the extremities of the bow making it have the stability of something longer. Advertising has compared it to a barbel with wights on the end as opposed to having the wights in the middle(short riser).  This is the geometry that has driven the "parallel limb design" movement seen in the archery market. It's a legitimately good design that has increased the stability of bows of all lengths, but especially that of the shorter bows.

The next major design factor of risers is their geometry. There are 3 kinds:

Straight Riser.  Pretty self explanatory. The limb pockets are in line with the grip on these and is a very forgiving of any twisting that may be put on the riser by poor grip or hand placement. Usually results in a medium to high brace height(distance from inermost part of grip to the string). Examples: PSE Mojo and Dominator

Deflex riser: Once very common, especially on target bows, this riser design put the limb pockets behind the grip, making it almost impossible to twist the riser with improper hand placement and resulting in a very high brace height (8''+). It's drawback is that the arrow spends very little time on the string to gather momentum(speed). Great for accuracy but extremely slow. That one thing has all but removed it entirely off the market. Examples: Hoyt Pro Elite, Mathews Apex

Reflex riser:  This design puts the limb pockets ahead of the grip. This design can still be stable enough if not taken to an extreme (more than 1 3/4" ahead of the grip) but is still the least forgiving. By far the most popular design because it causes a lower brace height which produces more speed. And speed is what sells bows. Bows with extreme reflex are known as speed or 'monster' bows and usually have wrist-slapping brace heights 6'' or less. These bow are the least forgiving of any design. Examples: Mathews Z7, Monster, Triumph, Hoyt Alphaburner, PSE X-Force

Brace height(BH): Brace height is measured from the shallowest point on the grip to the string.  Say you have 2 bows both set up at 29 inch draw but the first one has an 8 inch BH and the second has 6. The arrow will travel on the string for 21 inches on the first when shot. The arrow on the second bow will travel 23 inches, 2 inches more than the first, giving the shooter more time to affect the arrows flight after release making it less forgiving.

So if I still want a shorter bow, what should I look for?

A long, straight, or only slightly reflexed riser with parallel limbs and a higher (7"+) brace height. An 8" brace height would be best.