Getting the Most From Your Predator Rifle

How you choose and equip a predator hunting rifle affects where its bullets go, and whether you can tap the rifle's potential when you're in the field.

Getting the Most From Your Predator Rifle

With much yet to learn about firearms, I'm less an expert than a rifles enthusiast. Readers sharing that affliction write occasionally with questions. You’ll think some elementary; others lie deep in ballistic weeds. Elementary stuff matters most; the rest is arguably pointless for predator hunting.

George asked about barrel break-in, noting that everyone seems to have a different opinion. Alas, arguments for any break-in practice are hard to test with statistical reliability. Accuracy trials with two barrels, for example — one fired fresh, one "broken in" — don't tell much because many variables enhance and impair accuracy. Cleaning shows how much gunk you got from the bore, but spotless rifling doesn’t ensure tight groups. In prone competition, I fired fouling shots before moving to record targets. Neglecting this routine risked an orphan first hole.

Many repetitions with a specific centerfire load might net some conclusions regarding break-in of a specific barrel type, but think of how many rifling forms and twists, loads and bullets there are! Barrel steels differ too. In general, I think gently breaking a barrel in with mild loads and frequent cleanings is a good idea, as is breaking in an engine by varying its speed and load at modest RPMs. That said, today both barrels and engines are now made for people who don't break them in. I’ve fired old lever-action rifles that evidenced no bore care but delivered walnut-size groups at 100 yards.

Every component of a predator hunting rifle, from your sling to the ammunition, can affect how you shoot and your success. (Photo: Wayne van Zwoll)

Many factory barrels shoot exceedingly well straight from the box. Hand-lapped bores like Kenny Jarrett's relieve you of having to remove copper caught by microscopic machining burrs, but lapped bores must still be cleaned to perform their best. In sum, I follow no routine to break in barrels on hunting rifles. Those that disappoint are shot more to ensure they're beyond redemption; some improve. Groups that average a minute of angle with predator loads are small enough for me.

Questions about cleaning pop up often. Removing harmless powder and primer residue is as easy as a quick swab. Metal fouling is not so visible, however. A gleaming bore can still hold copper stripped from bullets. It traps moisture and tears at succeeding bullets, impairing accuracy.

Most bullet jackets are now 95/5, copper/zinc. Thick, almost-pure copper jackets on some bullets are more ductile and strip more readily. The tsunami of solid-copper (and copper alloy) bullets has pushed copper fouling higher on lists of barrel gremlins. Ammonia-based solvents lift copper; but they also eat at bluing and stock finishes, and brass brushes.

Whatever the bullet type, my cleaning procedure for centerfire rifles is straightforward. A Tipton or MTM rifle vise holds the rifle without marring it. A wicker basket snares patches and solvent spray from emerging brushes (as do receptacles like Muzzle Mate, Patch Hog and Splatter Box). I prefer a stiff one-piece steel rod with a spinning handle so patch and brush “take” the rifling freely. Steel rods won’t pick up grit as easily as soft alloy and Teflon-coated rods. Joints add flex and can batter bores.

With bolt-action rifles, I slide a polymer bore guide onto the cleaning rod before fitting a patch to the slotted jag. That guide centers the rod and keeps it from banging the rifling. An 18mm guide fits most bolt races; but Sinclair offers them for just about any rifle, including autoloaders, pumps and lever-actions that must be cleaned from the front. Even slight muzzle damage can affect accuracy.

When a long cleaning rod is unhandy, there’s the Otis Ripcord in a zippered “biscuit” pouch. The cable’s 10-inch cleaning section has Nomex synthetic fibers that “trap fouling better than nylon.” An Otis Elite kit boasts 40 components, with obstruction-clearing tools. The Gun Boss Pro by Real Avid, another portable option, boasts a polymer case that opens to hold a sturdy jointed brass rod, jags and brushes — .22 to 12-bore — at an easy angle.

The scent of Hoppe’s No. 9 revives for me memories of 22-cent gasoline, farms open to hunting with a knock on the door, and rifles proudly displayed in glass-fronted cases in living rooms. I use it for most bore cleaning. Ammonia-based solutions like Montana X-Treme’s Bore Cleaner, Barnes CR-10 and Copper Killer 50 BMG solvents annihilate copper deposits. Sweet’s 7.62 is so potent it should be wiped from the bore after only a few minutes. Pro-Shot, Shooter’s Choice and Bore Tech, and products from Wipe-Out, TM and Butch’s, target lead and copper. Ditto Witches Brew, from Holland Shooters Supply.

I remove the first solvent-soaked patch after one pass through a dirty bore, so as not to bring gunk back through. Next step: a solvent-soaked brush, eight passes, both ways. I follow with dry patches until they come out clean, finishing with a lightly oiled patch to guard against rust. Then I ditch the bore guide and spin an oiled shotgun swab against the chamber wall.

Keith asked about barrel length, given the trend to shorter barrels on hunting rifles, and long ones for long shooting. Barrel length has little to do with accuracy. In fact, shorter barrels often shoot better, as they're stiffer. (Remington XP-100 bolt-action pistols commonly shoot into one hole.) Still, a longer barrel hikes velocity. The .22 Long Rifle is an exception. It has a tiny case, only as broad as the bullet, and uses very fast powder; so it achieves top speed in barrels about 16 inches long! We are accustomed to the traditional look and balance of .22s with barrels longer than 16 inches, and their generous sight radius.

Early lever-action rifles had barrels of 22 to 28 inches. They gave tube magazines great capacity, but added weight and pulled balance well toward the muzzle, especially when the rifle was fully loaded! Winchester’s 94 and Marlin’s 336 were most popular with 20-inch carbine barrels — long enough to wring lethal velocity from relatively fast powders in cases of modest capacity. Bolt-rifle rounds like the .30-06 and .270 benefited from 24-inch barrels because cases held more fuel. In addition, because there was substantial diameter reduction from hull to bullet base, the powder was slower, building pressure to accelerate bullets more gradually as the big cloud of expanding gas sought release through a relatively small bore. The high speeds of those bullets increased friction, which also limited burn rates. Heavy charges of slow powders require more barrel length to transfer all their energy.

When belted magnums like the .257 Weatherby, .264 Winchester and 7mm Remington appeared, they were initially paired with the 26-inch barrels standard for their forebear, the .300 H&H. In the 1950s, Winchester introduced M70 Featherweights, with 22-inch barrels. The Featherweight in .264 Winchester Magnum reportedly lit cigars at 20 feet. New powders have improved short-barrel efficiency and blessed shooters using suppressors, which add nothing to bullet speed. Still, 24- and 26-inch barrels have a place.

The easiest way to determine the ballistic effects of changing barrel length is to chop a long barrel incrementally shorter. Trials by A-Square with a .300 Winchester barrel recorded velocities from 28 to 16 inches. Loads of 70.5 grains IMR 4350 with150-grain Nosler Ballistic Tips and 78.0 grains RL-22 with 180-grain Sierras yielded these results:

Note that the rate of velocity loss increased as the barrel was cut shorter than 20 inches for both bullets – the result of cutting into the bell of the pressure curve. I’ve no such data for common predator cartridges like the .223, .243 and .25-06, but you can infer similar results with similar bore/case capacity ratios and equally slow powders.

Hornady’s .300 and .338 Ruger Compact Magnums, announced in 2008, were designed to deliver high speed in carbine-length barrels. Project lead Mitch Mittelstaedt explained to me that new proprietary powders “tightened” pressure curves so the .300 RCM acts like most .30 magnums in 24-inch barrels but doesn’t lose as much enthusiasm in carbines. “Velocity of .300 WSM bullets falls 160 to 180 fps when barrels are lopped from 24 to 20 inches; RCMs lose 100.” Ken Oehler’s 35 chronograph gave me readings of 2,840 fps with 180-grain bullets from a 20-inch Ruger barrel. Impressive!

Another barrel-length issue is fore-stock length. When Winchester introduced its Featherweight Model 70 with 22-inch barrel, the stock was the same as that on standard and magnum rifles with 24- and 26-inch barrels. The Featherweight looked odd to those of us in love with the proportions of early 70s. Remington’s Model Seven, conversely, was designed to complement 20- and 22-inch barrels. Installing a longer barrel gives this rifle a naked, skeletal appearance up front.

Enough of cosmetics. Rifling twist for a given cartridge, once a standard figure, is now for some cartridges a variable. Thank long bullets designed for distance. The longer the bullet, the sharper the twist needed to stabilize it. At its 1964 introduction, the .223 was deemed best served with a 1-in-12 twist. Therefore, it was — given the original 55-grain load. Bullets used in the .223 now range from 40 to over 75 grains in weight. A 1-in-12 twist has given me good accuracy with bullets to 62 grains and, in some rifles, 64. But faster spin is usually recommended for long bullets 62 grains and above. Matching your load to the rifling twist is a first step to better accuracy.

The other end of your rifle matters too. Good stock fit helps you hit. Ordering a driven-bird gun from a London house, you’ll be fitted with an infinitely adjustable “try-gun” to get just the right measure of pull, pitch, drop and cast-off, the perfect feel of grip and comb. No fox hunter I know has shelled out the shekels for a fitted rifle stock, but length of pull is easy to change. Installing a thick recoil pad to add length, or lopping the butt to reduce it, is best done by someone with experience. Galco, the holster-maker, has a quick and esthetically pleasing alternative to installing a new pad. Its slip-on leather pad hews to the stock profile with a Velcro tab that latches over the toe. Adjustable stocks, once available only on costly target rifles, now appear on sporting rifles from Savage, Ruger and others.

Stock fit affects the position of your face on the comb and, thus, proper placement of the scope. Above the bridge of my nose there’s a half-moon of permanent scar tissue, testament to a life squandered shooting rifles scoped by somebody else. When the eyepiece of a scope is too far back, it will bang you in recoil. It will hit you hardest in prone, because your head is tilted forward, and your body cannot rock back as it does offhand. It will also bite you if sitting or when shooting uphill.

Many scopes are attached with the rifle on a bench or in a cradle, eye relief checked with a casual toss to the shoulder, standing. Few shooters check it prone, or point the rifle as they might a shotgun, head forward, body leaning to the target for a fast offhand shot. Result: most scopes sit too far back. Your head should slide forward naturally, as you mount the rifle, so it achieves the common 3 ½-inch eye relief gap and the scope’s full field just as you’re ready to fire. If you must move your head back and forth to find correct eye relief, you waste time and put your head in an unnatural position for the shot. Want to know if your scope is too far back? Try moving it ahead half an inch. I’ll bet you like it better there!

Questions on bedding, like those on barrel break-in, prompt a wide range of responses. I’m out of space here; we will revisit that topic later. Before making any major alteration to your rifle, consider first what most affects field accuracy: your ability to steady the sight and fire without disturbing it. A bipod or a shooting sling like the Brownells Latigo I use will reduce wobble. A trigger tuned for a light, consistent let off — or replaced by one from Timney — smooths bullet release. Then there’s basic marksmanship. I’ve muffed shots with supremely accurate rifles! Another topic for another time.

Featured image: Wayne van Zwoll



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