Post by Woody Williams on Sept 22, 2005 9:59:31 GMT -5
Some helpful hints!
I hope this is of some use to you!
By: Tom Doyle
The only way to assure accuracy with your crossbow is to tune it just before the start of each hunting season. Although tuning appears to be complicated, it's really simple. There are four easy steps:
1) Basic inspection and tightening of components (general maintenance);
2) Confirming string, brace height, tiller, and retainer-clip condition;
3) Bolt (arrow or quarrel) set-up;
4) Pin sights or scope adjustment.
Why, you may ask, do I need to retune if the bow was okay last season? Time is not kind to mechanical devices, crossbows included. Did you relax or unstring the limbs at the end of last season? If not, they might react differently than when last used. A bow stored in hot or humid conditions has its integrity challenged. As well, if you change to new bolts or switch fletching, retuning is in order.
Also keep in mind that every time a bolt is released, vibration occurs. Periodically check all securing nuts, bolts, and screws for tightness. To avoid serious bodily injury, replace limbs that have cracks or stress fractures. A stiff, jerky trigger mechanism results in poor accuracy, so keep it lubricated. WD-40 or the like are better choices than gun oil or grease, as they won't freeze.
When a bowstring turns fluffy, it should be replaced. Infrequent waxing of string and flight deck contribute to string demise. Follow manufacturer specs when replacing a string, especially if you're considering a fast-flight. Not all crossbows are capable of using these strings without damaging the limbs. Check with an archery pro shop before installing one. It will increase bolt speed, but not enough to beat a string-jumping deer. The downside from a non-shock-absorbing fast-flight string is more noise from already noisy limbs.
To maintain proper string position, mark it when at rest on either side of the flight deck by using a piece of white thread or whiteout. When the bow is cocked, these indicators should always be equal on either side of the flight deck. If not, accuracy suffers. I've found that using a rope cocker is the answer.
Once you've taken care of the string, make sure the flight deck is free of damaging nicks or burrs. If the brace height is too low, put a few twists in the bowstring to raise it. Check the manufacturer's specs and set accordingly.
Also check the tiller. Improper tiller stresses limbs and scatters bolts. An even tiller is needed to create equal pressure on the limbs. This can be measured from the base of the limbs to the string on either side of the flight deck. If they're not the same, adjust the limb bolts.
And don't forget the bolt retainer-clip. Only enough pressure is needed to keep the bolt in place and parallel to the flight deck. A twisted retainer clip can put off-centre pressure on the bolt, causing erratic flight.
Now turn to your bolts. Stick to the weight recommended by your bow's manufacturer. The speed gain of a lighter arrow is of little advantage. It will probably shorten the life of your bow, and you'll lose valuable penetrating power. More useful to improve accuracy, if your bolts aren't already so equipped, is switching from plastic to 5-inch feathers with a slight helical curve.
Broadheads need not be in line with the fletching, but should be adjusted for conformity, so they group together. Tighten a broadhead on a bolt and spin it on an arrow checker. When you get it to spin true, fix the other broadheads to the same angle in relationship to the fletching. This creates the same air flow over the fletching, which steers the bolt. Now head for the range.
Start target shooting with field points at 10 yards. Instead of using a regulation-size bull's eye, mark a quarter-size spot on the target butt. This gives you a tighter focus and a better grouping. With this achieved, set up the remaining distance pins or scope references. If you shoot with the cock feather in the shooting groove, shoot all the bolts the same way. When on target, breathe in, hold your breath, squeeze (not pull) the trigger, and then breathe out. After a time, this becomes automatic.
With field-point accuracy achieved, now shoot with broadheads. Don't expect them to hit the same spot as the field points, which have less wind resistance, making initial tuning easier. For bull's eye accuracy, though, all that's left to do is adjust your crossbow's pin sights or scope again for broadheads. Your crossbow will be in perfect tune and singing a sweet song this hunting season.
I hope this is of some use to you!
By: Tom Doyle
The only way to assure accuracy with your crossbow is to tune it just before the start of each hunting season. Although tuning appears to be complicated, it's really simple. There are four easy steps:
1) Basic inspection and tightening of components (general maintenance);
2) Confirming string, brace height, tiller, and retainer-clip condition;
3) Bolt (arrow or quarrel) set-up;
4) Pin sights or scope adjustment.
Why, you may ask, do I need to retune if the bow was okay last season? Time is not kind to mechanical devices, crossbows included. Did you relax or unstring the limbs at the end of last season? If not, they might react differently than when last used. A bow stored in hot or humid conditions has its integrity challenged. As well, if you change to new bolts or switch fletching, retuning is in order.
Also keep in mind that every time a bolt is released, vibration occurs. Periodically check all securing nuts, bolts, and screws for tightness. To avoid serious bodily injury, replace limbs that have cracks or stress fractures. A stiff, jerky trigger mechanism results in poor accuracy, so keep it lubricated. WD-40 or the like are better choices than gun oil or grease, as they won't freeze.
When a bowstring turns fluffy, it should be replaced. Infrequent waxing of string and flight deck contribute to string demise. Follow manufacturer specs when replacing a string, especially if you're considering a fast-flight. Not all crossbows are capable of using these strings without damaging the limbs. Check with an archery pro shop before installing one. It will increase bolt speed, but not enough to beat a string-jumping deer. The downside from a non-shock-absorbing fast-flight string is more noise from already noisy limbs.
To maintain proper string position, mark it when at rest on either side of the flight deck by using a piece of white thread or whiteout. When the bow is cocked, these indicators should always be equal on either side of the flight deck. If not, accuracy suffers. I've found that using a rope cocker is the answer.
Once you've taken care of the string, make sure the flight deck is free of damaging nicks or burrs. If the brace height is too low, put a few twists in the bowstring to raise it. Check the manufacturer's specs and set accordingly.
Also check the tiller. Improper tiller stresses limbs and scatters bolts. An even tiller is needed to create equal pressure on the limbs. This can be measured from the base of the limbs to the string on either side of the flight deck. If they're not the same, adjust the limb bolts.
And don't forget the bolt retainer-clip. Only enough pressure is needed to keep the bolt in place and parallel to the flight deck. A twisted retainer clip can put off-centre pressure on the bolt, causing erratic flight.
Now turn to your bolts. Stick to the weight recommended by your bow's manufacturer. The speed gain of a lighter arrow is of little advantage. It will probably shorten the life of your bow, and you'll lose valuable penetrating power. More useful to improve accuracy, if your bolts aren't already so equipped, is switching from plastic to 5-inch feathers with a slight helical curve.
Broadheads need not be in line with the fletching, but should be adjusted for conformity, so they group together. Tighten a broadhead on a bolt and spin it on an arrow checker. When you get it to spin true, fix the other broadheads to the same angle in relationship to the fletching. This creates the same air flow over the fletching, which steers the bolt. Now head for the range.
Start target shooting with field points at 10 yards. Instead of using a regulation-size bull's eye, mark a quarter-size spot on the target butt. This gives you a tighter focus and a better grouping. With this achieved, set up the remaining distance pins or scope references. If you shoot with the cock feather in the shooting groove, shoot all the bolts the same way. When on target, breathe in, hold your breath, squeeze (not pull) the trigger, and then breathe out. After a time, this becomes automatic.
With field-point accuracy achieved, now shoot with broadheads. Don't expect them to hit the same spot as the field points, which have less wind resistance, making initial tuning easier. For bull's eye accuracy, though, all that's left to do is adjust your crossbow's pin sights or scope again for broadheads. Your crossbow will be in perfect tune and singing a sweet song this hunting season.
