Crossbow Troubleshooting: 8 Common Problems and What to Check

When a crossbow starts acting up, with groups opening up, shots drifting to one side, a string that looks fuzzy, or a trigger that won’t release, the cause is usually something simple you can check at home. This guide walks through the most common crossbow problems, what typically causes each one, and what to check, in a sensible order. It also tells you when to stop and take the crossbow to a professional.

Safety first: stop and get it inspected if…

• the crossbow was dry-fired (fired with no bolt);
• you see a crack, chip or splinter in a limb;
• the string or a cable has broken strands or a damaged serving;
• a cam is bent, wobbling or the cables have come off track.

Don’t shoot it again until the manufacturer or a qualified archery shop has checked it. These problems can lead to sudden, violent failure.

Problem 1: Groups are getting bigger

Common causes and checks:

1. Loose hardware: check the scope rings, scope mount, limb bolts and stock screws. Vibration loosens them over time.
2. Bolt problems: spin-test bolts for wobble, and check for loose inserts, damaged vanes or cracked nocks. Number your bolts so you can spot one that always flies wide.
3. Inconsistent cocking: if the string isn’t centred when cocked, shots drift. Using a rope cocker or crank helps keep it even.
4. Shooter form: a consistent cheek weld, a steady rest and a smooth trigger squeeze matter as much as the equipment.

Problem 2: Shots consistently hit left or right

• Canting: tilting the crossbow even slightly moves impact sideways at longer ranges. A scope with a level, or an add-on bubble level, shows you. See what canting is.
• Off-centre string: mark the centre of the string and rail. If the string sits off-centre when cocked, re-cock carefully with a cocking aid.
• Scope zero: if everything else checks out, adjust windage and re-zero (see how to sight in a crossbow).

Problem 3: The scope won’t hold zero

• Re-tighten scope rings and mounts to the torque in the manual. Don’t overtighten.
• Make sure the scope is designed for crossbows; crossbow vibration is different from rifle recoil.
• Check that the scope is calibrated for your crossbow’s actual speed if it’s speed-adjustable.

Problem 4: Fuzzy, frayed or worn string

• Fuzzy string: it needs wax. Wax it as often as your manual says, typically every few dozen shots or when it looks dry.
• Wear on the centre serving: that serving rubs the rail on every shot. Lubricate the rail as recommended, and have the serving replaced when it wears through.
• Broken strands: replace the string. Don’t shoot it.

Our maintenance guide covers waxing and rail lubrication step by step.

Problem 5: The trigger won’t release, or the safety won’t disengage

• Anti-dry-fire not satisfied: most crossbows won’t fire unless the bolt is fully seated against the string. Check that the nock is touching the string and, for half-moon nocks, oriented correctly.
• Wrong nock type: some crossbows require a specific nock. Check your manual.
• Debris in the trigger area: dirt or ice can interfere. Keep it clean and dry.

If the crossbow is cocked and won’t fire, don’t force it. Point it in a safe direction, keep your fingers clear, and follow your manual’s procedure, or take it to an archery shop.

Problem 6: Bolts fall off the rail or sit loose

• Check the bolt retention spring for bending or wear.
• Make sure you’re using the bolt length and diameter the manufacturer specifies.

Problem 7: Louder than it used to be

• Look for loose accessories: quiver mounts, scope, sling studs.
• Check string suppressors and limb dampeners for wear.
• A dry string is often noisier, so wax it.
• A sudden change in noise can signal damage. Inspect the limbs and cams.

Problem 8: Broadheads hit somewhere different from field points

• Use broadheads of the same weight as your field points.
• Check that the broadheads spin true on the bolt, and that they’re compatible with your crossbow’s speed.
• Shoot your broadheads into a broadhead-rated target and adjust your zero if needed before you hunt. See choosing crossbow broadheads.

Quick diagnosis table

Symptom	Check first	Then
Wider groups	Loose scope or screws	Bolts, then cocking consistency
Consistent left/right miss	Canting	String centring, then windage
Fuzzy string	Wax it	Check the serving for wear
Won’t fire	Bolt and nock seated	Trigger area debris; consult the manual
New noise	Loose accessories	Inspect limbs and cams
Dry-fire or visible damage	Stop: professional inspection before any further use

Frequently asked questions

Why is my crossbow suddenly inaccurate?

The most common causes are a loose scope or mount, a damaged bolt, and inconsistent cocking. Check those first, in that order.

What should I do after a dry fire?

Stop shooting and have the crossbow inspected by the manufacturer or a qualified shop before using it again.

How often should I wax my crossbow string?

Follow your manual. Many manufacturers suggest every few dozen shots, or whenever the string looks dry or fuzzy.

Can I fix cams or replace a string myself?

Most compound and reverse-draw crossbows need a crossbow press for string and cable work. Unless you have the tools and training, use an archery shop.