How to Give Your Crossbow a Tune-Up
July 21, 2016
A quick look at hunting demographics shows most of us are old enough to remember those campy Ronco TV ads.
They hawked all sorts of gadgets designed to make our lives simpler, like Popeil's Pocket Fisherman and the Chop-O-Matic, later lampooned by Saturday Night Live's Dan Akroyd as the Bass-O-Matic. Then there was the Ronco Rotisserie and its famous tag line: "Just set it and forget it."
Those infectious slogans are often re-purposed for all manner of applications, sometimes to our detriment. For example, a good many folks probably think the rotisserie pitch also applies to crossbows; set them up and they're indefinitely ready to shoot.
After all, simplicity is part of their appeal. And while crossbows don't require the same level of maintenance and tweaking as compound bows, there are some basic steps you need to take to keep your crossbow performing its best.
Strings and Cables
Strings and cables are the most vulnerable part of your crossbow, so we'll start there. You need to inspect them on a regular basis. Because of the string-to-rail contact, crossbow strings experience far more friction and abrasion than strings on vertical bows.
Barb Terry, director of customer relations, training and education for TenPoint Crossbow Technologies, recommends you look carefully at the center serving. "If the string was improperly installed (without the required amount of twists) the serving may separate and the actual bowstring may be exposed, which could cause the string to break when the crossbow is fired," Terry said. Even the repeated shock of normal use can cause serving to loosen and unravel over time.
You can reduce the probability of problems and lengthen the life of your strings and cables with some very simple regular maintenance.
Bobby Vargas, product line manager for PSE Archery says, "Cables and strings should be kept clean and well maintained after every practice session or hunting trip. The center servings and rails should be well lubed for best long-term performance."
"...while crossbows don't require the same level of maintenance and tweaking as compound bows, there are some basic steps you need to take to keep your crossbow performing its best."
Terry recommends lubricating the rail every 75-100 shots with light oil, or every 150-200 shots when using high-performance oil. Simply add a small drop to each side and rub it in. Don't over-lubricate, as too much oil can saturate the serving and shorten its life. Also avoid petroleum jelly or wax on the serving, as both will collect dirt and debris.
"But wait," you say, "my bow came with a tube of string wax." It did indeed; and that's exactly what it's for: your string. Apply it along the length of the string (except the serving) and burnish it in with your fingers by rubbing quickly to create heat. You should do this as often as you would with light oil on your serving, every 75-100 shots.
Even with the most meticulous maintenance, your string and cables will eventually wear out and need to be replaced. When that will occur depends largely on the amount of use, but Terry suggests replacing string, cables and draw cords every other year with high use and every three to four years with occasional use. When you do, replace both your string and cables, as even steel cables will stretch over time.
Keep It Tight
You should also inspect and tighten all fasteners on a regular basis. While most of the energy is transferred to your bolt at the shot, a fair amount is also absorbed by your rig, which can loosen screws and/or nuts. Check all the stirrup setscrews, main assembly bolts and setscrew, stock screws, barrel (rail) screws and scope mounts.
Speaking of scopes, in addition to ensuring fasteners are secure, you'll also want to check that sights are still zeroed on a regular basis — before every hunt. And you should keep the glass clean and clear with a lens pen or cloth. If you have an illuminated scope, replace the battery on a regular basis, at least annually. You might even want to carry a spare in your pack.
One of the most often overlooked components is the trigger assembly. Vargas advises a periodic inspection to make sure it's clean, free of debris and in good working condition. Clean all moving parts with pressurized air or a dry brush, then lubricate according to manufacturer's specifications.
Recommendations may vary on the amount and type of lube. Synthetic, non-petroleum based lubes are typically a better choice as they're less likely to gum up and collect debris or stiffen in extreme cold.
While doing your routine inspections, you should also check the limbs, stock and other synthetic parts for cracks or other signs of fatigue. You can also do a cursory inspection of your bow's mechanics.
For anything beyond basic maintenance such as lubrication, cleaning and tightening, consider seeking professional help from your local pro shop. They're better equipped and experienced in everything from quick fixes to complete overhauls.