Q: I shoot a PSE Pro Series compound bow with an adjustable draw weight of 60-70 pounds. I'm using Blackhawk Vapor carbon arrows with a spine strength of 4000, and 125-grain field points with 32-inch arrows. My draw weight is set at 65 pounds with 70 percent let-off. The bow has a five-pin sight mounted on it, and I'm using a mechanical release. At 10 yards I'm shooting 3 inches low and 3 inches right, but the arrow groups are consistent. At 20 yards I can't hit the target at all. How do I adjust the sights to get on target? -Jonathan Loveless/Burleson, TX
A: The short answer to your accuracy problems is to move your sight pins more to the right and lower on the sight bracket until your shafts are hitting where you're aiming. I'd also try shooting Blackhawk Vapor 5000s instead of 4000s for your draw length and bow poundage. Also, if your current arrows are straight fletched I'd switch to fletching (either feathers or vanes) that's offset 1-2 degrees. I'd also invest in a high-quality arrow rest for your bow because your arrow rest not only affects arrow spine value, but it also controls shaft clearance. Each is essential for accurate arrow flight. I'd also consider adding a rope or metal string loop to your bowstring, which should give you better broadhead flight. Good luck and good shooting! -M. R. James
Q: I have three vintage Jennings compound bows that I'm trying to find parts and original prices for. I've tried contacting the manufacturer directly to no avail, so I'm hoping you can help me out.
-Robert Bradley/Livingston, NY
A: While antique stores have experienced a popularity explosion in this country, they've yet to embrace vintage compound bows. That said, I forwarded your question to two senior members of our "Bowhunting Advisory Council." Judd Cooney contacted a number of sources without success. Jim Dougherty then replied and said his "old friend Tom Jennings has moved to South America" and that the person "who was doing all the old Jennings repairs" had recently retired.
Since we don't want to leave you completely hanging, here are a few other options. First, try eBay. You can find almost anything on this popular Internet auction site. I did a quick search for "Jennings bows" on eBay and found several vintage bows along with their original owner's manuals. You can also try the Archery History Web site (visit www.huntingclub.com for a direct link). By posting a request for Jennings equipment on this site you might be able to locate a selection of vintage Jennings bows. Finally, you can try researching established Jennings and Bear dealers. They might employ a knowledgeable pro shop technician with the history, equipment and information you seek. -Mark Kayser
UNDERSTANDING KINETIC ENERGY
Q: I've read that a kinetic energy of 50 foot-pounds or more is good for big game such as elk and caribou. Does kinetic energy change at different yardages? If so, what yardage is being used for the 50 foot-pound standard? -Kenneth Mecom/Clinton, IA
A: A bow's energy is stored in its limbs and cams when drawn, then transferred to the arrow shaft at the shot in the form of kinetic energy. Because the speed of the shaft is reduced due to both gravity and air resistance, the kinetic energy also changes along the flight path. Thus, the kinetic energy you measure a few feet in front of the bow as the arrow's released is different from the kinetic energy that's delivered downrange to the target. That's why when hunting large animals such as elk, experienced bowhunters try and "juice up" their bows to deliver more initial kinetic energy and thus more kinetic energy to the target.
My personal minimum for elk-sized game is approximately 60 foot-pounds of initial kinetic energy. Your goal should be to achieve maximum arrow penetration. The formula for determining kinetic energy is arrow velocity squared multiplied by arrow mass and then divided by 450,240. "Arrow mass" is the weight of the arrow shaft measured in grains and "arrow velocity" is the arrow speed measured in feet per second.
My current setup is a Mathews Switchback bow set at 73 pounds and 28 1/2-inch Gold Tip Pro Hunter 7595 carbon shafts topped with 125-grain broadheads that weigh a total of 449 grains each. With this setup, my arrows have an initial velocity of 267 fps and a resulting kinetic energy of 71.1 foot-pounds, which is more than enough for any North American big game animal. -Bob Robb