Compound Bow

What a compound bow does that other bows don't

A compound bow uses cams, the wheel-like parts on the limb tips, plus cables and a string. Archery 360 explains the trick: as you reach full draw, the cams roll over and cut the weight you hold. That's let-off. Then a draw stop, where the cam meets a limb or cable, ends the draw at the same spot every time, so the power stroke is identical shot to shot.

Archery 360 also notes that every compound is built to take a rest, a sight and a stabilizer, and that compound archers often use a mechanical release aid. A hunting bow, in practice, is the bow plus four or five accessories. Sights are on the bow sight page and releases on the bow release page.

The table on this page lists every compound bow we track on Amazon US, from the highest IBO speed down. It shows the draw weight and draw length ranges, let-off, cam system, whether it adjusts without a bow press, the package type and hand as the maker or the Amazon listing states them (the table marks values that come from the listing), plus mass weight, axle-to-axle and brace height from the maker. A dash means neither states that value. Youth, target and package bows also have their own pages, linked further down.

How to choose a compound bow: the specs in order

Fit first, feel second, speed last. That's the order of the specs below, and it's the order the table's columns matter in the woods.

Start with draw length, because it's a fit, not a preference

Draw length is how far you pull the string for proper form. Archery 360's draw length guide estimates it from wingspan: arms out in a T, fingertip to fingertip, divided by 2.5. A shop can measure it properly with a draw board or a marked arrow. On a compound, it's measured from the nocking point to the deepest part of the grip, plus 1¾ inches.

The table shows each bow's draw length range. How a bow gets there varies, per the same guide:

• Draw-length-specific modules: one module per length, swapped by a technician
• Adjustable modules: one part with several settings, often in ¼- or ½-inch steps
• Highly adjustable cams: wide ranges with no new parts and no bow press, common on youth and beginner bows; Archery 360 says these generally don't perform as well as traditional compounds
• Draw-length-specific cams: mostly older bows; a change means a new cam, a press and a technician

Field & Stream's advice is to round down if you land between lengths. A little short beats a little long.

Pick draw weight you can pull smoothly, inside the bow's range

Draw weight is the pounds of force to pull the string back. The table shows the stated range, for example a bow that adjusts from 60 to 70 lb.

Archery 360 says compound hunters commonly shoot 50 to 70 lb, and that a state's minimum for deer is usually about 35 lb. (That's a typical figure. Your state sets its own, so check your state wildlife agency.) Its target-bow guide adds that most compounds have about a 10-lb adjustment range and usually perform best at the top of it. So if you want to shoot 60, a 60-lb max bow is a cleaner fit than a 70 backed all the way down.

Field & Stream's check: sit on the ground, hold the bow out and draw it straight back. If you have to tilt the bow up or yank, it's too heavy. Recheck before every season.

Choose the hand by your dominant eye

Right- and left-handed bows are mirror images. Archery 360 says to match the bow to your dominant eye and hand when they're on the same side. Its eye test: thumbs up, cover a distant object with both eyes open, then close each eye. The eye that keeps the thumb on the object is dominant.

If your eye and hand don't match, you're cross-dominant, and Archery 360 suggests trying both setups at a shop. The table's "Hand" column shows what the maker or the listing offers: right, left, either, or ambidextrous.

Let-off sets how much you hold at full draw

Let-off is a percent of peak weight. Archery 360 says it goes as high as 90%. Quick math: a 70-lb bow at 90% holds at about 7 lb; at 80% it's 14 lb; at 65% it's about 24 lb.

More let-off is easier to hold while a deer decides whether to step out. Less let-off gives you more weight to aim against, which is why Archery 360 says many target archers prefer 65 or 70%. Some bows offer adjustable let-off. The table lists the maker's maximum.

Axle-to-axle length: maneuver or steady

ATA, axle to axle, is the distance between the axles the cams turn on. Archery 360 says hunting compounds run about 27 to 34 inches, and target compounds generally 34 to 40.

goHUNT's breakdown:

• Up to 31 inches: generally faster and easier to maneuver in tree stands and ground blinds, often a rougher draw
• 32 to 33 inches: the middle
• 34 inches and up: generally a smoother draw, somewhat lower speed, steadier at full draw

Archery 360 adds that longer bows reduce string angle, which suits taller archers with long draws. If you hunt a tight blind, short helps. If you hunt from a field edge and practice at long range, longer helps.

Brace height trades forgiveness for speed

Brace height is the distance from the deepest part of the grip to the string at rest. goHUNT sets the line at about 6.5 inches. Over that is more forgiving, because the arrow leaves the string sooner, and usually smoother but slightly slower. Under it is faster but less forgiving, because the arrow stays on the string longer.

"Forgiving" here means small mistakes in your form move the arrow less. For a hunter shooting once, cold, after two hours in a stand, forgiveness counts.

Cam system: how the draw feels

The table's "Cam system" column uses the maker's or listing's term. Archery 360's spec guide sorts the main designs:

• Single (solo): a round idler wheel on top and an elliptical cam on the bottom; a smooth draw, slower speeds
• Hybrid: a control cam on top and a power cam on the bottom; faster than solo-cam bows
• Binary: synchronized top and bottom cams that turn in unison
• Dual: two cams with an aggressive draw for more speed and kinetic energy

If you want to go deeper on single cams, there's a single-cam compound bow page.

Mass weight is the bow alone

Mass weight is what the bare bow weighs, before the sight, rest, quiver and stabilizer go on. The table shows the maker's figure. Plan on the finished hunting rig being heavier. If you'll carry it a long way or hold it a long time, the lightest compound bow page sorts by that number.

IBO speed: read it last, and read it as a lab number

IBO speed is a standardized rating. Grand View Outdoors and one bow maker's FAQ describe the conditions: 30-inch draw, 70-lb draw weight, a 350-grain arrow (5 grains per pound), and a bare string. Change any of those and you lose speed.

Grand View walks a 340-fps bow down step by step. A 29-inch draw costs some speed, a peep and two silencers cost more, 60 lb costs more, and a 400-grain arrow lands it below 300. Archery 360 puts typical hunting setups at 270 to 285 fps, well under the 350-plus on spec sheets.

My one opinion on this page: for a deer hunter, IBO speed is the least useful number in the table. The reason is that test setup. Few hunters shoot a 30-inch draw, 70 lb and a 350-grain arrow all at once, so the rating ranks bows against each other and tells you little about your own arrow.

Adjustable without a bow press

The table marks bows whose maker or listing says draw weight or draw length adjusts without a bow press. That's handy for a new archer still finding a draw weight, and Archery 360 notes that many budget compounds are highly adjustable so they grow with the archer. Bows that adjust widely have their own page: adjustable compound bow.

Bare bow, ready to hunt, or kit with arrows

The "Package" column shows one of three:

• Bare bow: the bow only; you choose every accessory
• Ready to hunt: the bow with the main accessories installed
• Kit with arrows: a package that also includes arrows

Archery 360 says most makers offer budget-friendly compound kits that include most of the accessories. Packages are covered on the compound bow package page. Whichever you buy, arrows still have to match your draw weight and length; that's on the compound bow arrows page.

How to change draw weight on a compound bow

This is the most common adjustment you'll make at home. One bow maker's FAQ and Field & Stream's maintenance guide agree on the steps:

1. Look up your bow's maximum number of limb-bolt turns out in the owner's manual.
2. Use the Allen wrench size your manual names for the limb bolts.
3. Turn counterclockwise to lower draw weight, clockwise to raise it, on most bows.
4. Turn the top and bottom bolts the same amount.
5. Check the result on a bow scale.

Field & Stream warns that going past the maximum turns can crack limbs, break limb pockets or let bolts pop out. Draw length is a different job. Modules and cams vary, and some changes need a bow press and a technician, so take that one to a shop.

Danny's contribution to this topic: "Lefty loosey works on bows too." He then turned the top bolt three times and the bottom bolt once. Same number of turns, both bolts. Every time.

Which compound bow for which job

A hunting bow for deer

Most hunting compounds sit around 27 to 34 inches ATA, with draw weights in the 50 to 70 lb band Archery 360 describes for hunters. Shorter ATA helps in blinds and stands. For a first bow, the best compound bow for beginners list starts from adjustability.

Target shooting

Archery 360's target guide points to longer ATA (34 to 40 inches), smoother cams, lower let-off and draw weights at or under 60 lb, the USA Archery and World Archery limit. Those bows are on the compound bow for target shooting page.

Compound bow and target, for backyard practice

A compound needs a target rated for its arrows. Archery targets are sorted on the archery target page. Practice with field points into a backstop you trust.

Youth and smaller archers

Shorter draw lengths and light draw weights need a bow built for them. That's the youth compound bow page.

Care and safety

Oregon's wildlife department lists the basics: wax the string regularly, check strings and cables for fraying, and inspect cams, limbs and riser for cracks or delamination. Don't shoot a bow you suspect is damaged. One bow maker's FAQ suggests waxing about every 500 shots and in wet weather. Archery 360's spec guide suggests replacing string and cables about every three years, depending on how much you shoot.

Never dry-fire a compound bow. Archery 360 says releasing the string without an arrow can bend cams, crack limbs, snap the string and send parts flying, and compounds suffer most because they have the most moving parts. Don't let anyone draw your bow who doesn't know how. If it's ever dry-fired, a pro shop inspects it before the next shot.

Who should skip a compound bow

If you want the simplest bow with nothing to adjust and no release aid, a recurve may suit you better; see the recurve bow page. If you're weighing a crossbow instead, the crossbow vs compound bow guide lays out the trade-offs.

Everyone else: get measured, pick a draw weight you can pull smoothly, and write both numbers in the logbook.