Sporting Firearms Journal

®

RIFLERIFLE

Display until 6/12/17 Printed in USA

May 2017 No. 292

TESTED: Stocky’s NewLong-Range Stocks!

Looking Back: World War II Semiautomatics

Win a Custom6.5 Creedmoor Rifle!

Enter HANDLOADER’s50th Anniversary Giveaway

See Page 57 for Details

Haenel-Mannlicher9x57 mauser

New HornadyBullets for the.25-35 WCF

Updated Researchon Rifle BarrelTwist Rates

Rifle 292www.riflemagazine.com

COLUMNS

6 Ken Waters (1917-2017) Spotting Scope - Dave Scovill

8 Mossberg Rifles and Sheep Hunting Lock, Stock & Barrel - Lee J. Hoots

12 Leverguns and Varmint Cartridges Mostly Long Guns - Brian Pearce

16 Winchester Model 1873 Down Range - Mike Venturino

18 Big-Bore Plinker Project – Part I Light Gunsmithing - Gil Sengel

22 Varmint Scopes A Rifleman’s Optics - John Haviland

44 Ellis Brown .450 No. 2 Nitro Express Custom Corner - Stan Trzoniec

62 Hawkeye Borescope Walnut Hill Terry Wieland

FEATURES

26 Haenel-Mannlicher 9x57 Mauser One Unusual German Stalking Rifle Terry Wieland

32 .25-35 WCF Field Testing Hornady’s New Bullets and Loads Brian Pearce

38 World War II Semiautomatics Reviewing a Trio of Venerable Rifles Mike Venturino

46 Stocky’s Long- Range Stocks Field Testing a Pair of New Model 700 Handles John Haviland

52 Modern Rifling Twist Realities Updated Research on Twist Rates and Accuracy Issues John Barsness

On the cover . . .This Haenel-Mannlicher 9x57 Mauser was made before 1910. Photo by Terry Wieland. Inset photos: A new long-range stock by Stocky’s Stocks.

4

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Page 44 . . .

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Page 22 . . .

22 www.riflemagazine.com Rifle 292

About the time the first green of spring appears, a hunter’s

fancy turns to varmint shooting. In days gone by, preparing for spring shooting required little more than dusting off the modest scopes on rimfire and centerfire rifles and sighting in the rifles. Today’s scopes are not so modest, and choosing one is an involved mat-ter. Decisions on selecting a scope abound from a variable’s magnifi-cation range, a plain or complex reticle and turrets to leave as set or dialed to mesh with a bullet’s trajectory.

In 1983 I bought a Ruger M77 Varmint .22-250 Remington and a contemporary Burris 10x scope. The fixed-power scope with plain crosshairs was considered fairly cutting edge at that time. The pair provided great fun shooting ground squirrels and marmots and revealed a lot about estimat-ing range, holdover to compen-sate for range and doping the wind. My notes state the majority of my shooting was between 70 and 400 yards, and I “missed a lot by over-shooting.” The .22-250 is still a great cartridge for long-dis-tance shooting. Today, however, that scope is considered nearly Neolithic.

Once in a while I wished for different magnifications than pro-vided by the straight 10x scope. A variable-power scope’s magnifica-tion options provide a wider field of view and a closer look. A scope set on 6x or 8x provides a wide field of view to help scan a field to spot ground squirrels. A wide exit pupil, at that lower power, provides some positioning leeway for a full view. A scope set much over 10x magnifies quivers when walking around and resting a rifle on shooting sticks or on a gopher mound. Shooting with the support of a bench, I turn magnification up and down to match the conditions of distance and mirage. Usually it ends up set on 12x, perhaps 14x.

Often it’s lower, to see through mi-rages from midday heat simmering above a green field. Still, it looks like gophers are dancing around like fairies in a mist. The cool of the morning is about the only time the air is clear enough to dial to higher magnification. Even then, scopes with high ends of 20x and above are never dialed that high.

With that power comes the need for a large objective lens. A 42mm diameter objective lens suits vari-ables that top out at 16x, and 50mm matches scopes that turn up to 20x. A scope with a large ob-jective lens does sit quite a ways above a rifle, but stocks with ad-justable comb height prevent a shooter from having to crane his

A RIFLEMAN’S OPTICS by John Haviland

varMint sCopes

A scope that tops out at 14x offers plenty of magnification for rifles chambered for cartridges like the .223 Remington.

The higher a variable power scope’s magnification, the larger its objective lens should be – within reason, of course.

A riflescope that is adjustable for parallax helps provide precise aiming on long shots.

An elevation turret set for a specific load is quick to dial for shooting different distances.

24 www.riflemagazine.com Rifle 292

neck to see through it. A folded towel draped over a comb also raises the eye and is handy to dab sweat from your brow while suf-fering under the spring sun.

The old method of placing a ret- icle above a target to compen-sate for bullet drop was just too vague to guarantee a hit. That led to reticles with hash marks on the lower vertical wire regulated for various ranges. These different aiming points only came into ad-vantageous use with the arrival of laser rangefinders that provided an exact distance to a marmot perched on a distant rock. Some of these reticles were so complex

they cluttered the view and con-fused the eye. The obvious step to simplify the view was to use a plain vertical crosshair (and hori-zontal crosshair with hash marks for windage correction) with yard-age marks on the elevation turret that correspond to a specific load.

The Custom Dial System (CDS) turret for a Leupold VX-R 4-12x 40mm scope is set to match the trajectory of Nosler 50-grain Bal-listic Tips fired at 3,450 fps from my .223 Remington. The CDS tur-ret rotates one revolution, which is enough adjustment to compensate for the Ballistic Tip’s drop out to 650 yards with the scope zeroed at 200 yards.

Limiting a scope to one load does seem rather restrictive, but if the load is changed to a 69- grain HPBT with a muzzle velocity of 2,966 fps, I refer to a note that states three additional clicks past the 300-yard setting will bring the heavier and slower bullet dead-on at that distance; five added clicks at 400 yards, and so on.

With any of these reticles, ac-tual shooting is required to verify they mesh with the real trajectory. One of my favorite rifles for mar-mot shooting is a Cooper Firearms Model 22 .243 Winchester shooting Nosler 70-grain Ballistic Tips at 3,306 fps. I mounted a Swarovski X5(i) 5-25x 56mm P scope with a 4WX reticle on the rifle. To create a trajectory chart for that load, I logged onto the Swarovski ballistic program (ballisticprograms.swar ovskioptik.com) and keyed in the bullet weight and its ballistic co-efficient, muzzle velocity and el-evation. A chart appeared that included inches in bullet drop in 50-yard increments and elevation corrections in minutes of angle (MOA) to compensate for bullet drop at the various ranges.

At 100 yards, two bullets cut the right edge of the half-inch aiming square, and the third bullet hit the top of the square. The three bullets landed in a .79-inch group. The wind raised its ugly head while I was shooting at 200 yards. The ballistic chart indicated one MOA of elevation was required to

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hit dead-on at that distance. Three bullets landed even with the aim-ing square in a 1.35-inch group. Shooting at 300 yards, the wind blew toward the rifle from every which way. I dialed up 2.75 MOA, and three bullets hit perfectly for elevation, but 2 inches right of the bullseye. I aimed to the left about a third of a 2 MOA hash mark and shot twice. The bullets hit an inch to the left of the bullseye – good enough to knock a prairie dog off its mound. A few min-utes later the wind kicked bul-lets 4 inches to the right with the same hold. Wind is the bugaboo of long-distance shooting.

I watched a Nightforce optics employee shoot only a few shots to find the correct elevation turret settings to hit targets at 450 and 700 yards. The Nightforce ATACR 4-16x 50mm scope he was dialing in was on an Accuracy Interna-tional rifle shooting Black Hills .308 Winchester cartridges loaded with Sierra 175-grain Tipped MatchKing bullets. He knew the ballistic coefficient of the Match-King bullets, their velocity from the rifle and that the rifle was sighted in at 100 yards. He typed those numbers, plus the tempera-ture, humidity and elevation into a ballistics program on his smart-phone. He then dialed the nec- essary clicks on the Nightforce’s elevation turret to compensate for the program’s stated bullet drop. His first shot was a bit low on the target at 450 yards. He turned up the elevation turret a few more clicks, and the second shot hit right on the money. Adjusting the turret for the 700-yard target put two bullets in the center of a steel plate way out there.

Varmint shooters would spend half their day fiddling with an el-evation dial if they adjusted it for each shot. Say a cluster of ground squirrels infests a field a ways ei-ther side of 350 yards. Using an aiming point or dialing for that dis-tance, a rifleman can eyeball how much to hold over or under and for the wind for those fluctuating distances with skill learned from shooting with a plain reticle.

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May-June 2017 www.riflemagazine.com 25

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John Barsness

To understand the latest in-formation on rifling twist, we need to understand why bullets fly point-forward. The

spin imparted by rifling gives a bullet gyroscopic stability, the force that al-lows a spinning top to remain upright – but unlike a top, a bullet flies through the atmosphere, sometimes at speeds

over 4,000 feet per second. As a re-sult, air pressure pushes against the front of the bullet, like wind against a soda can lying in the street – a strong enough wind overcomes the can’s weight, sending it tumbling across the pavement. Much the same occurs when the “wind” on a bullet over-comes its gyroscopic stability; instead of flying point-on, the bullet tumbles through the air.

Modern Rifling Twist Realities

Slower rifling twists will stabilize long, high-BC bullets in the thinner air of higher elevations. This E.R. Shaw 6.5-06’s barrel has a relatively slow 1:9 twist but stabilized a 140-grain Berger VLD very well at 7,000 feet above sea level.

Updated Research on Twist Rates and Accuracy Issues

Rifle 29252

25 inches (1:25) will stabilize this bullet.

The formula worked pretty well with the blunt, all-lead bul-lets universal in Greenhill’s day, though slight modifications were often made after the appearance of smokeless powder and jacketed bullets. Some rifle enthusiasts still use the formula, but it’s also re-sponsible for the misconception that a given bullet will always be stabilized by a certain twist rate. This isn’t true, because air varies considerably in density due to tem-perature, elevation and humidity, resulting in variations in air pres-sure on the front of a bullet.

Colder air is far denser than warmer air and at higher eleva-tions is much thinner than at sea level. Humidity plays such a mi-nor role it can be ignored except at very long ranges – although, un-like many people assume, “wet” air is actually less dense that dry air. This is because water mole-cules (H2

O) contain two hydrogen atoms and one oxygen atom, and hydrogen is lighter than oxygen.

In denser air, a bullet may not stabilize when shot in a certain ri-fling twist but may in thinner air. The Greenhill formula doesn’t in-clude air density, perhaps because it was devised from observations in relatively cool, low-elevation England, so any change in atmo-spheric pressure was likely to re-sult in thinner air.

Many shooters also believe bullet weight is the major factor in rifling twist, because bullet manufacturers often recommend a specific twist rate for bullets of certain weights. In reality, bul-let length is most important, the reason the Greenhill formula also doesn’t include bullet weight, and why “lead-free” bullets won’t sta-

The result is the “correct” rifling twist, expressed in how many inches a bullet travels down the bore during one revolution. As an example, using a .458-caliber, 500-grain, roundnose bullet mea-suring 1.25 inches long: .458 x 150 x (.458 ÷ 1.25) = 25.17 inches. Thus a rifling twist of about one turn in

Modern Rifling Twist Realities

Even though electronic anemometers, like this Minox variant, can measure wind speed where a shooter stands, both wind velocity and direction can vary over longer distances.

Some humans have a compul-sion to convert almost any aspect of the universe into a mathemat-ical formula. This often causes other humans to fall asleep, but math makes constructing many nifty things possible, including pickup trucks, telescopic sights and rifle barrels. Consequently, many formulas have been de-vised to predict the rifling twists required to keep bullets point- forward. The best known is the Greenhill formula, developed in 1879 by a British mathematician, Sir Alfred George Greenhill.

Greenhill empirically developed a twist formula through testing bullets fired in different twists: Multiply bullet diameter by 150, then multiply the ratio of bullet diameter divided by bullet length.

May-June 2017 www.riflemagazine.com 53

Left, roundnose bullets will stabilize in slower rifling twists better than spitzers, even though there’s more “air pressure” on their blunt noses, because they’re shorter than spitzers of the same weight, and their centers of mass are farther forward. Right, the lightweight plastic tips of many modern high-BC bullets actually allow them to stabilize in slightly slower rifling twists than all-metal bullets of the same length.

ModernRifling TwistRealities

54 www.riflemagazine.com Rifle 292

bilize in twists that work for lead-core bullets of the same weight; lead-free bullets are longer, be-cause their metals are lighter than lead.

Manufacturers normally rec-ommend twist rates that stabilize a specific bullet in any environ-mental conditions. In warmer tem-peratures or at higher elevations, however, the same bullet will shoot well in slower twists. As a re-sult, some handloaders decide the bullet company doesn’t know what it’s talking about (or they’re excep-tional handloaders), because they can get the bullet to shoot well in slower twists. If they travel else-where, however, the bullet may not stabilize. This happened recently to a friend here in Montana who shoots at a local range 5,000 feet above sea level. He worked up an accurate handload in one of his rifles with a rifling twist slower than the manufacturer recom-mended for that bullet, then went to Texas to hunt feral pigs, where the elevation was 4,000 feet lower. Upon arrival he shot his rifle to check the scope’s zero, and the bullets scattered so widely some missed the paper. Luckily he’d brought two rifles, and the other shot fine.

While roundnose or flatnose bullets obviously result in higher air pressure against their front

ends, they’re shorter than spitzers of the same weight, and their cen-ters of mass are farther forward. As a result, they stabilize in slower twists and denser air than spitzers of equal length.

Many handloaders also believe faster muzzle velocity helps sta-bilize a bullet, partly because they’ve seen accuracy improve while adding more powder when working up a load. There’s a kernel of truth here, but in reality extra bullet spin created by more veloc-ity only makes a tiny difference in bullet stability, because air pres-sure on the front of the bullet also increases. Plus, if a bullet’s being shot in what ballisticians call a “marginal” twist, it will desta-bilize in denser air, as my friend discovered in Texas. In reality, the primary reason more veloc-ity often results is smaller groups is that modern powders are de-signed to burn most consistently at near-maximum pressures.

Smaller-caliber bullets require

The original rifling twist of most military 6.5mm cartridges was around 1:8, the twist of the Lilja barrel on this custom 6.5x55. Even today’s lighter 6.5mm bullets still shoot well when “overstabilized.”

faster twists than larg-er-diameter bullets of the same length. This is why a .458 bullet that is 1.25 inches long sta-bilizes in a 1:25 twist, while a .277 spitzer of the same length nor-mally requires a 1:10 twist.

All these factors have affected bullet and cartridge development since the first practical smokeless rifle powders appeared. Most early smokeless cartridges were mili-tary, beginning with France’s 8mm Lebel in 1886, and used heavy, roundnose bullets, apparently be-cause the black-powder cartridges they replaced used heavy, round-nose bullets. The most prevalent bullet diameters were 6.5mm, 7mm, .30 and 8mm, and the long bullets required relatively fast rifling twists, around 1:8 in 6.5mm, 1:9 in 7mm and 1:10 in .30 and 8mm.

In 1898 Germany switched to a much lighter spitzer bullet in the 8x57, increasing range enor-mously. Other countries followed, but none changed the original ri-fling twists.

In contrast, during the same pe-riod, new sporting cartridges of-ten featured relatively light bullets at high muzzle velocity, because the extra zip flattened trajectory

over practical hunting ranges. One classic example is Savage’s .250-3000, introduced just before World War I. The .250’s original factory load featured an 87-grain spitzer at 3,000 fps in a 1:14 twist barrel, in order to avoid “overstabilizing” bullets.

Similarly, in 1925 Winchester came up with a brand-new bullet diameter for its brand-new .270 Winchester cartridge featuring a 130-grain bullet at a claimed 3,160 fps in a 1:10 rifling twist. Eventu-ally most .25-caliber rifles also had 1:10 rifling twists, but 1:10 would not stabilize heavy spitzers with really high ballistic coefficients (BC) in either .25 or .270 caliber. This didn’t matter to hunters, be-cause they rarely shot at ranges where higher BCs mattered – until laser rangefinders appeared on the civilian market in the late 1990s.

This is why 6.5mm and 7mm cartridges became far more pop-ular among long-range hunters than .25s or .270s. Shooting “flat” was no longer necessary, because new scopes provided compensa-tion for bullet drop. Instead, wind drift became the major variable, and heavy, high-BC bullets resist wind drift far more than lighter bullets at higher muzzle velocities. This is why very few truly high-BC .25 and .270 bullets are available: They won’t consistently stabilize in the standard 1:10 rifling twist.

It’s also the reason the predom-inant modern rifling-twist for-mula was devised specifically for

Even into the 1980s, some companies used the origi-nal 1:14 twist for the .250 Savage, the reason John used the relatively short Speer 100-grain bullet in his Winchester Model 70 Lightweight. The bullet was probably just barely stabilized on this cold day.

high-BC boat-tail bul-lets. It was created by the late Don Miller, a retired rifle loony who had the desire, time and knowledge to fool around with twist num-bers. I first met Don

years ago at the annual SHOT Show, because he was interested in a couple of my simplistic ballis-tic formulas.

During our conversation, Don gave me a copy of an article he’d written on his new twist formula, which became the basis for the for-mulas used by companies involved in long-range shooting, including Berger Bullets and JBM Ballistics. Though the Miller formula is far more complex than Greenhill’s, it can still be worked on a pocket calculator. (If I can do it, many people can.) The easiest method is to use the Internet, logging onto www.bergerbullets.com or

May-June 2017 www.riflemagazine.com 55

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56 www.riflemagazine.com Rifle 292

www.jbmballistics.com and plug- ging the numbers into the online formulas (see sidebar).

I’ve been using the Miller for-mula for at least a decade now, and due to living in Montana, where

both elevation and temperature vary considerably, I can testify it’s very accurate, but any poten-tial user should know some other details.

First, many shooters still be-lieve overstabilizing bullets re-sults in poor accuracy, but today’s well-balanced bullets shoot very well even when used in “too much” twist – which increases BC, im-portant in longer-range shooting. Many shooters also believe the BC of a given bullet is a fixed number, when in fact it’s pretty flexible and with high-BC bullets increases with both velocity and rifling twist.

The symbol “Sg” is shorthand for gyroscopic stability. An Sg of 1.0 means a bullet is just barely stabilized, but overstabilizing a bullet up to 1.5 Sg increases bal-listic coefficient by up to 15 per-cent, so the bullet flies flatter and drifts less in the wind.

Another common misconcep-tion is that bullets destabilize as velocity drops, resulting in poorer accuracy at longer ranges. Many shooters have “proven” this to themselves by shooting at lon-ger ranges, finding their one-inch groups at 100 yards often expand not to 4 inches at 400 yards but to 8 or 10 inches.

In reality, bullets become more stable as range increases. A bul-let’s spin slows only slightly as it flies through the air, while velocity drops rapidly, resulting in far less air pressure on the front of the bul-let. The exception is when velocity drops to around the speed of sound, about 1,100 fps at sea level, but very few spitzers from modern hunting cartridges slow to “transonic” ve-locities within 800 yards, and most don’t until beyond 1,000 yards.

Instead, the major reason for larger groups at longer ranges is wind. Wind drift increases at ap-proximately four times the rate of range, and most hunters aren’t very good at “reading” wind or compensating for its effects. As an example, a one-mph breeze (which most hunters would call absolutely calm) results in about 1.5 inches of wind drift at 400 yards with a typi-cal 180-grain bullet from a .30-06,

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Modern tWist forMula notes

The Berger and JBM versions of the Miller formula differ in some ways. The Berger formula doesn’t provide any allowance for plas-tic-tipped bullets, probably be-cause Berger doesn’t make any, while the JBM formula does. When using the Berger version, I usually subtract .75 inch of the length of the tip from a plastic-tipped bul-let’s overall length.

The Berger version also pro-vides a calculation of ballistic co-efficient for bullets between 1.0 and 1.5 Sg, and JBM’s doesn’t. This “adjusted” BC can come in very handy at longer ranges.

The JBM formula uses baromet-ric pressure rather than elevation, expressed as “Hg.” An approxi-mate rule is that each 1,000 feet of elevation results in an inch less barometric pressure. Since

“normal” Hg at sea level is 29.92 inches; Hg at 5,000 feet above sea level would be around 25 inches.

and a relatively mild but inconsis-tent breeze of one to 4 mph will increase a 400-yard group’s size by up to 5 inches.

The Miller formula isn’t as accu-rate with flat-based bullets, which stabilize in slightly slower twists than predicted, probably because of extra drag on the rear of the bullet. It agrees, however, with the Greenhill formula that a 500-grain .458 bullet measuring 1.25 inches long stabilizes in a 1:25 twist, even at the typical black-powder muzzle velocity of 1,200 fps.

At the other extreme, Don Miller eventually decided the pointy plas-tic tips on many long-range bullets are so light they shouldn’t be fully included in a bullet’s overall length. As an experiment, I clipped the plastic point from a Nosler .30-cal-iber, 180-grain Ballistic Tip, and on my Redding scale it weighed 2.0 grains. Then I clipped off an equal length from the tip of a Berger hol-lowpoint 185-grain Hunting VLD. The lead core doesn’t extend into the tip in VLDs, yet just that short length weighed 7.0 grains, three-and-a-half times as much as the plastic tip. Obviously the differ-ence would be even more with the lead tip of a softpoint bullet.

Using the Miller formula helped me arrive at another useful twist statistic. Most rifling twists for modern, high-BC bullets range from 1:8 to 1:10, depending on cali-ber. Within that typical range, 5,000 feet in elevation is the equivalent of about an inch of rifling twist. Thus, a bullet the formula predicts will fully stabilize at sea level in a 1:8 rifling twist will perform about the same at 5,000 feet above sea level with a 1:9 twist, and at 10,000 feet in a 1:10 twist. I’ve confirmed this by shooting a bunch of bullets in rifles with varying rifling twists at various elevations in Montana. It’s why a handload with Berger 115-grain VLDs works pretty well in the 1:9 twist of my Ruger Amer-ican .243 Winchester in my corner of the state, where even in the val-leys, elevation averages around 5,000 feet. I wouldn’t take that load to South Texas.

May-June 2017

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