In The Field: Rifle sighting for hunters
Special to the Daily
I’ve been a big game hunting guide in Colorado for more than 25 years and have seen many missed shots due to loose screws holding barreled actions in stocks, loose scopes, rings and mounts. Most often, hunters spend little time shooting the particular rifle they will use while hunting.
For myself, I spend most of my target time with heavy, accurate rifles like the .223 Remington 6.5 x 284 or .308 Winchester, firing 500 to 700 rounds per season. I don’t spend much time shooting my favorite hunting rifles: .338 Winchester Magnum, .300 Winchester and 30-06 T3 Light. With heavy recoil on these three, you feel discomfort after 20 to 30 rounds.
Before sighting, I follow the same routine for a hunting trip and first check the firearm to be sure it is unloaded. I then clean and check all fasteners to be sure everything is tightened correctly (refer to manufacturer for recommended torque settings). Case the rifle and select proper ammunition for the hunt, then pack proper eye and ear protection.
Now, head off to the range. We’re fortunate here in Summit County to have a no-fee shooting range located at the landfill off U.S. Highway 6 east of Dillon. This shooting range exists due to the hard work of Summit County Commissioner Thomas Davidson and Summit County Manager Thad Noll, along with countless hours put in by volunteer range safety officers.
When you arrive at the range, take your unloaded and cased firearm to a covered bench at the 100 yard range. Ask the range safety officer (RSO) or another shooter for a range closer to set a target at 25 yards. Make sure the flag is down before moving forward of the firing line. Targets are available at the range for a small donation.
When the range is open, return to bench, uncasing your rifle and opening the action. Stabilize your rifle with sandbags or other appropriate materials. Align the bore and sights with the target. If they do not line up, adjust the sights until they do. This is bore sighting, generally only required when new sights are installed.
Load one round and fire at the target. Ideally, you should be close to center. If you have a new firearm, or have added or changed sights, this is the beginning of the sighting-in process.
Most modern sporting scopes have elevation and windage adjustments of quarter-inch clicks at 100 yards. At 25 yards, make 16 clicks to move the impact point one inch on the target (again, refer to manufacturer’s data).
Next, move the target to 100 yards. When safe at the bench, fire three rounds for a group. Most cartridges for hunting will hit somewhere between two and three inches high at 100 yards if the zero in was done at 25 yards. If your hits are off, make quarter-inch adjustments up, down, right and left until you are centered and two to three inches high.
Why do you want to be high at 100 yards? The trajectory for a 30.06 with a 150-grain bullet at 2,700 feet per second will be two inches high at 100 yards, zero at 200 yards and 7 inches low at 300 yards. For most uses, this will enable you to hold center of mass from 25 yards to 300 yards and be assured of a hit. This seems like a lot of room for error, but most shooters would be happy with a three-inch group at 300 yards. You should shoot 20 to 40 rounds at the range to feel ready for hunting.
To put this in perspective, my best 20-shot group in competition (standing at 100 yards slow fire, with a 14-pound AR-15) was 2.73 inches, scoring 199 out of 200 with 7x hit. This particular rifle was capable of shooting 0.51-inch, 5-shot groups on the bench with match ammo.
When you are satisfied with your sight-in group, thoroughly clean your rifle at the range. Before casing your rifle and leaving, fire one round. This is called a fouling round. Do not clean the powder residue, as it will not harm your bore. This procedure is the best way to get ready for your hunt.
Colorado big game hunting information is available for deer, elk, pronghorn, moose and bear from Colorado Parks and Wildlife at 303-297-1192 or cpw.state.co.us
Good luck shooting, hunting and enjoying the outdoors.
Dale Fields is a fourth generation Coloradan and full-time resident of Summit County since 1982. He lives with one wife, two dogs and three cats
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