How to shrink groups from a new hunting gun or restore the glory of Ol’ Betsy
By John Haviland
Sometimes new rifles don’t shoot as well as we’d like, or worse, a previously dependable rifle goes off its feed. Operator error is often the culprit with a rifle that throws bullets across a target like a slingshot flinging rocks. When the gun itself is the problem, though, a simple tweak or two often are often all that’s needed to correct it.
Try Different Loads
Custom gunmaker Charlie Sisk sees a lot of shooters frustrated with the accuracy of their rifles. “A rifle right out of the box should be able to shoot 2-inch groups or less at 100 yards with factory ammunition,” he says. “Most of them will do that, too.”
However, every rifle has its idiosyncrasies. Sisk recently built three identical rifles in .308 Winchester. The customer planned on shooting 150-grain Nosler Ballistic Tips in all three guns. Two of the rifles shot the bullets very well. The third threw them all over half an acre.
Sisk tried every type of 150-grain bullet he had with the same results. Finally he tried 165-grain Ballistic Tips. The rifle put five of them in nearly the same hole.
“Those three guns were made with the same chamber reamer, barrels, rifling twist and stocks,” Sisk says. “You tell me why that one rifle shot so much better with 165-grain bullets.”
Because each gun is unique, hunters should experiment to find the load that’s most accurate in their rifle.. Buy at least a few boxes of different factory loads, or split the cost with a friend to find the load your rifle likes best.
Even the best factory ammo or handloads occasionally fail to fly where we aim. The following remedies save having to go to church twice on Sunday for swearing up a blue streak on Saturday over an inaccurate rifle.
Scopes & Mounts
Before heading to the range, make sure your scope base(s) and rings are tight. Often, both short and long screws are used to attach a base to a receiver. Mixing them up and using the long screws to secure the front of the base gives the appearance of a tight fit. The screws are tight, all right, because they have bottomed out in the screw holes. But the base remains as loose as a barn door banging in the wind.
Sisk recommends a thread bond like Loctite on screws to keep bases from moving.
Screw-on rings used on hard-kicking magnums may require a dab as well. “Check the screws often, too,” he suggests, “because they work loose under recoil.” A rifle that shoots two distinct groups or one that resembles a pattern of buckshot are sure signs of loose scope rings or bases.
We are forever changing our minds and scopes on rifles, so to break the bond on the screws, Sisk recommends holding the tip of a soldering iron on the screw head for a few minutes. The heat loosens the grip of Loctite so screws can be easily removed.
A scope reticle that fails to track is easily checked by clamping the rifle in a vise, placing the crosshairs on a target with 1-inch squares, and watching the crosshairs move as the adjustment dials are turned.
Sometimes scopes suddenly fail after years of service. A scope might not respond to adjustments, even after twisting the reticle knobs like a radio dial.
A scope on my .270 Winchester rifle provided good service for years. Two years ago, it started to only grudgingly move its reticle, requiring three times as much adjustment as it should have. The following day, it aimed off toward the moon. I finally gave up and replaced it with a new Nikon 4-power scope. I figure the ammunition I will save fighting the old scope will pay for the Nikon in five years.
The advice has always been to mount a scope as low as possible over the barrel so you don’t have to crane your neck for a full field of view. But don’t mount the scope too low. Sisk once mounted a Burris scope on a Sako rifle chambered in 7mm STW. The scope’s objective bell cleared the top of the barrel by 3/10 inch. When Sisk shot the rifle, it scattered bullets all over the target. “I took it back to the shop and tried to find the problem,” he recalled. “I happened to notice the Teflon on the barrel right under the objective bell was scratched off, so I fixed that while I was at it.” The rifle didn’t perform any better on the next trip to the range.
Then Sisk noticed the Teflon was scraped off again in the same place. That long Burris scope and the free-floated barrel were whipping on recoil and hitting one another.
To correct the problem, Sisk supported the barrel with glass bedding compound the full length of the barrel channel. That reduced whip and kept the scope and barrel separate.
Sisk says anybody who can follow directions can successfully glass-bed a riflestock. He recommends bedding at least the recoil lug, the receiver and 1 or 2 inches of the barrel ahead of the receiver.
Sisk prefers to bed his custom rifles the entire length of the barrel channel. “This dampens barrel vibration and also helps stabilize the threaded joint where the barrel screws into the receiver,” he says. “A rifle with full-length barrel bedding will shoot a wide variety of bullets more accurately than a free-floated barrel.”
Some people prefer free-floating barrels, but just because a dollar bill slips between the barrel and stock, though, doesn’t mean it’s free-floated.
To prove the point, put an even coat of a marking agent like lipstick on the barrel, put the barrel back into the stock (without touching the barrel channel) and then fire five rounds. Remove the barrel from the stock again. Marks on the channel show where the barrel whips during recoil and hits the stock. This, together with loose receiver screws, can slam the action and barrel around in the stock, causing bullets to land here and there.
The triggers on some factory rifles drag like a rusty gate latch. The pressure to trip triggers pulls a rifle to the side and takes attention away from holding the crosshairs steady.
“But don’t tinker with a trigger,” Sisk warns. “Take it to a gunsmith and let him adjust the weight of pull and remove the creep and overtravel.”
Sisk likes a 2- to 3-pound trigger pull on a hunting rifle. A somewhat heavier pull is a good idea for hunting in cold weather when fingers lose some of their feeling due to the cold or when a shooter is wearing gloves. Creep and overtravel in a trigger cause shots to fly wide. As long as they’ve been eliminated, a somewhat heavy trigger pull is manageable.
Steadying the Gun
Inaccuracy can often be traced to the shooter. A well-placed shot starts with a solid shooting platform and sandbags to steady the rifle. Good shooting form at the bench smooths wobbles. Feet flat on the ground, fairly erect posture, trigger hand lightly holding the rifle and the forearm of the other arm laid across the bench top to steady your upper body all contribute to a steady hold.
Only people with a diminished flow of blood to the brain can shrug off the kick of a big magnum rifle fired from the bench.
“You know how you sometimes get a headache when you shoot a hard-kicking gun?” Sisk asks. “Well, what you’re really getting is a slight concussion.”
Sisk recommends a muzzle brake and a thick recoil pad to tame recoil. A muzzle brake directs powder gases to the side or back toward the shooter, so muzzle blast is much louder and the shock waves cause the eyes to water. Ear plugs and muffs and protective glasses shield against that.
All recoil pads are not equal. Some are hard as a tractor tire and transfer all of the recoil to your tender shoulder. Recoil pads like the Kick-Eez are made of Sorbothane, which cushions kick by dispersing the shock of the recoil. Pick a pad thick enough so it doesn’t bottom out during recoil.
“I know I can’t shoot quarter-inch groups all the time,” Sisk notes. “But if a rifle shoots on the poor side, I check for these usual problems. It’s a good bet one of these solutions will restore accuracy.”
Reprinted from the July 2007 issue of Buckmasters GunHunter Magazine. Subscribe today to have GunHunter delivered to your home.