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August - September 2003 Volume 38, Number
4 ISSN: 0017-7393 Number 224 |
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On the
cover... The Savage Model 16 features a stainless steel barreled action mounted in a synthetic stock with a 6x Nikon Monarch UCC scope. Rifle photo by Stan Trzoniec. Caribou photo by Ron Spomer. |
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Its rare that any new
cartridge, whether wildcat or factory, is introduced to fill a genuine ballistic need.
After all, humans have been introducing smokeless centerfire cartridges since about 1890.
How many gaps are there?
Instead, the vast majority of new
cartridges appear because:
1) A
certain manufacturer hasnt introduced a .224 for misting snails or a .338 for
whacking whales, but everybody else has. This has been going on since the beginning of
cartridges. Browse through Cartridges of the World some time, particularly the sections on
British cartridges and obsolete American cartridges. Various companies were
cranking out proprietary rounds of the same basic design long before the
recent Short Magnum wars.
2) An
older cartridge would do snails or whales just fine, but many old rifles cant be
trusted with modern pressures. The 7mm-08 Remington doesnt do anything the 7x57mm
Mauser hasnt been doing since 1892 - but all 7mm-08s are modern, so
commercial ammunition can be cranked up.
3) Somebody
wants something different, to make the other boys in hunting camp jealous. This is the
case with 99 percent of the wildcats introduced since the .222 Remington appeared in 1950.
Most are minor variations on something that first appeared before 1951, but minor
variations deserve name changes. The name might as well be yours.
The other one percent of wildcats
truly fill some limited purpose. The PPC cartridges shrunk groups a tiny fraction of an
inch of .222-based cartridges so took over the benchrest world. Dave Scovills .338
and .375 rounds, based on the 9.3x62mm Mauser case, combined the largest case capacity in
a .30-06-sized round with a wider selection of bullets than then available in 9.3mm.
(Since then several new 9.3mm bullets have appeared, so the Scovills dont have quite
so much purpose. Will they go the way of the .333 OKH, which transformed itself into the
.338-06 after the introduction of the .338 Winchester Magnum? Only time will tell. Maybe
Dave should introduce the .366 Scovill.)
One of the most sensible and useful
American wildcats developed since World War II is just about dead today. The 8mm-06's
ballistics and bullet selection are plenty for about any North American game from
pronghorn to moose, and the cartridges fit and feed handily in any action suitable for the
.30-06. Yet few rifle loonies shed a tear for the round.
But 8mm-06 rifles are fine
illustrations of a slice of American history and the human determination to hunt. In the
years just after the war, factories took awhile to switch back to sporting rifles. Demand
far exceeded supply. The steadiest source of modern rifles came from the war itself. Many
returning soldiers brought 98 Mauser military rifles back from Europe, and more captured
rifles soon arrived, to be sold at very cheap prices. Some were used as-is for most
hunting, but most were cheaply converted into sporters.
The only problem was ammunition.
American sporting ammunition in 8x57mm was scarcer than liberals in Idaho. You could
re-form .30-06 brass (also cheap, especially if you bought war surplus) to
8x57, but it was a time-consuming pain in the butt. Far easier was to rechamber an 8x57
for the .30-06 case necked up to 8mm.
I chanced upon just such a rifle one
day while browsing through the consignment rack at Capital Sports & Western. The rifle
belonged to the father of one of the stores owners and was built by a gunsmith in
the Lewistown, Montana, area some time after the war.
The rifle wouldnt appeal to
any modern rifle snob, but for the time and place it was semi-deluxe. I know a couple of
Montana old-timers who still hunt with Mauser military rifles that are basically straight
from the factory. They never saw any sense in spending good money on a rifle that was
ready to shoot elk, though one guy did discard the hand guard and sawed off half the
military forend.
This 8mm-06 had quite a bit of work
done on it, aside from rechambering, including fitting an after-market stock and
converting the action to accommodate a scope. The bore had some light pits but was mostly
shiny, and an old one-piece Redfield mount was screwed onto the action. It was such a
perfect slice of history (and the price so low) that it came home.
According to the markings, the
action was made in Brno in 1943, after the Germans took over Czechoslovakia. Its
more finely finished than most wartime 98s Ive seen; the bolt even has the rib
called the bolt guide, eliminated on many late-war rifles. None of the steel
was altered except for three scope-mount holes and welding on a new bolt handle. The new
handle is a fairly deluxe touch on such rifles; most just have the military handle bent
down.
The military floorplate/magazine box was
retained, complete with screws. The boxs serial number doesnt match the
action, but the number on the stamped floorplate does. An after-market low-scope safety
was substituted, and a Timney Sportsman trigger fitted.
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The military steps in
the barrel were lathed off; the contour now strongly resembles a Winchester Model 70
Featherweight barrel. The stock is a plain piece of walnut with a large cheekpiece but
doesnt have any hint of the Weatherby styling, then coming into vogue.
There are no lightning-bolt inlays, no rollover monte carlo comb, no angled forend tip
with white spacer. There isnt even a white line on the Speed Cushion
ventilated recoil pad. Its just an honest stock in fairly classic style and
completely glass-bedded from the front of the action to the tip of the barrel, along with
a dab under the rear tang. This was the high-tech postwar equivalent of pillar
bedding, and similar miracles were claimed.
I mounted a 2-7x Compact from
Sightron, a newer company that makes excellent, rugged scopes. The next step was the
loading bench. I had plenty of 8mm bullets from past projects, plus mounds of .30-06 brass
but no 8mm-06 dies. After obtaining a set of RCBS dies, the work began. The dies
themselves were okay, but the expander ball was very roughly machined. Necking up .30-06
to 8mm meant really leaning on the press handle, so I stuck the decapping rod in my DeWalt
1/2-inch drill and polished the expander ball with some medium-grit emery cloth. That made
necking up 40 Norma .30-06 cases much easier.
Data for the 8mm-06 is still quite
common; the calibers listed in the latest Hornady, Nosler, Sierra and Speer manuals.
The bullets on my shelf ranged from 150 to 220 grains, and if youre really serious
an even wider range is available. Hornady still offers a 125-grain varmint bullet, and
Woodleigh makes a 250-grain roundnose bonded-core. I didnt try either, but anyone
determined to use an 8mm-06 for everything from prairie dogs to Cape buffalo has the
option. Fact is, many handloaders who select a 7mm, .30 or .338 because of the wide range
of available bullets would perhaps be even better served by an 8mm. (See load table.)
Most 8mm-06s are more likely to be
used for the common American big game menagerie from pronghorn to elk and moose. In theory
the 8mm-06 should be capable of a little more velocity than the .30-06 with the same
bullet weights, but the theory is pretty slim.
By crunching some numbers, Ive
found that potential muzzle velocity increases at one-fourth the rate of bore area. The
bore area of a .30-06 is .0745 inch, while a .323-inch 8mms bore area is .0819 inch,
an increase of almost exactly 10 percent. Divide 10 percent by 4 and we get a potential
velocity increase of 2.5 percent, or about 60 to 80 fps, depending on bullet weight.
This doesnt show up in most
manuals, because the majority of 8mm-06s are built on old military Mausers that vary
widely in quality. Its also about the variation we get in a couple inches of barrel
length or even individual barrels of the same length. The reality is that we should
generally avoid trying to push the 8mm-06 past .30-06 velocities.
Some astute readers might point out
that even at the same velocities, a spitzer 220-grain 8mm would shoot flatter than the
typical roundnose 220-grain .30-caliber slug. Lets compare a 220-grain Hornady 8mm
(listed ballistic coefficient .464) with Noslers 220-grain .308-inch Partition
(listed BC .331). Lets even give the 8mm-06 another 100 fps of muzzle velocity, even
though we shouldnt.
Sight them both in at 200 yards, and
the inefficient .30 roundnose started at 2,500 fps is down about 7.5 inches at
300 yards, 17 inches at 400. The sleeker 8mm at 2,600 is down about 6.5 inches at 300, 13
inches at 400. We gain an inch at 300 yards, 4 inches at 400.
The 8mm-06 loses out to the .30-06
at the other end of the bullet scale by similar trivial amounts. Mostly this is because
150-grain 8mm bullets have such low sectional density (.205) that its ballistic
coefficient is pretty pitiful. Hornady lists its at .290. Speer is more optimistic, with
.369, but Id bet the Hornady numbers more realistic. Most 150-grain .30s start
around .350 and go on up over .400. This means the '06 will shoot an inch or two flatter
at 400, even if the 8mm bullet is started 100 fps faster.
In short, there just isnt any
real difference between the two calibers. You could use either in the field forever, and
deer, elk and bear would fall just fine if you did your job. All the same, theres
nothing wrong with 8mm, despite Americas long-standing disdain for the bore, which
here in the good, old U.S.A. ranks down below the 6.5mm, .35 and probably even sewer rats.
The 8x57 was probably the cause. During the
early years of smokeless cartridge evolution, the Germans developed two bore diameters for
the 8mm, the older .318 inch and the newer .323 inch. (These are often called S and J, but
in various reference books, I have found no consistency about which is which. In Normas
latest catalog, for instance, one 8x57 is called JS and the other JRS. Let us leave this
mystery to the Europeans, only noting that all bullets mentioned here are .323 inch in
diameter.)
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In Europe the difference between the
8mm's is commonly known, and ammunition produced for both. Over here we never saw any
reason to differentiate, so loaded 8x57 ammunition to very low pressures, just in case a
.323-inch bullet got accidentally shot through a .318-inch bore. Only Federal and
Remington load the 8x57 today, using a .323-inch, 170-grain bullet at a supposed 2,360
fps. I say supposed because Ive chronographed some that barely beat the
velocity of 170-grain .30 WCF ammunition. No wonder the 8x57 never really captured the
American psyche!
In Europe the cartridge is still
very popular, and ammunition is loaded warmer. For instance, Norma loads its .323 version
with a variety of 196-grain bullets (including the excellent bonded-core Oryx) to over
2,526 fps. This load does fine work on larger European game, whether red deer, wild boar
or Scandinavian alg, the animal we call moose.
Even John Taylor, the ivory poacher
who wrote the classic African Rifles and Cartridges, recommended the 8x57 as a
medium bore. Though Taylor was distinctly prejudiced toward English
cartridges, he particularly liked the German 8x57 loading featuring an H-mantel 244-grain
bullet at a little over 2,000 fps, saying it was an infinitely more satisfactory
cartridge than the British .303. Taylor claimed to have used the 8x57 on most
varieties of game, including two or three elephant.
Theres even a European
equivalent of the 8mm-06, the 8x64mm Brenneke, that appeared in 1912 not only in both
.318- and .323-inch versions but also rimless and rimmed. (And Americans think buying a
box of 7mm mags is difficult today!) The factory loads for the 8x64mm closely
resemble the results of my experiments.
I found the 8mm-06 a very easy
cartridge to work with. The first range test indicated that published data was a little
low in this particular rifle, but despite the relatively low velocities and
primitive rifle, nine, three-shot groups averaged 1.2 inches at 100 yards.
This is from a 60-year-old wartime military barrel measuring a rather slim (for 8mm) .6
inch at the muzzle, in a stock rather crudely bedded by todays standards.
The second range session upped the
loads some. With the exceptions of Ramshots Big Game and Norma 204, all the powders
selected were those suggested by the Nosler and Sierra manuals as most accurate with
particular bullet weights. I decided to try Big Game with 150-grain bullets because of the
excellent luck encountered with 150s in the .30-06. It did not disappoint, though if I
ever hunt with the rifle Id probably bypass 150s entirely, using the 180-grain
Nosler Ballistic Tip for pronghorn- to caribou-sized game. This is one of the above
.30-caliber Ballistic Tips with a much heavier jacket. My friend Tim Crawford has used it
on three continents from the 8x57R rifle barrel in a German drilling and so far has only
recovered one bullet, from a big Argentinean red stag (about the size of a large caribou)
taken with an angling shot.
For larger game Id pick any of
the heavier bullets tested. This rifle seems particularly fond of the 196-grain Norma
Oryx, at any speed. I decided it deserved to be shot with a Norma powder as well, and N204
appeared to be the best candidate, since its burning rate is a little slower than the
4350s - about like Reloder 19 - Nosler best of show with 180s. I started off very
low just to be safe, and the combination proved to be one of the best of the entire test.
In summation, the 8mm-06 is just as
good as the .30-06, a cartridge any sane person (some rifle loonies arent) will
admit does a fine job on any non-dangerous game on earth. The real disadvantage, of
course, is that we cant go into a sporting goods emporium in British Columbia,
Argentina or South Africa and buy a box of factory loads. That has never discouraged real
rifle loonies though. If for some reason they get separated from their home-grown
ammunition, they can generally borrow somebody elses .30-06.
Once the American
sporting rifle industry cranked up again in the 1950s, the 8mm-06 lost its real reason for
being. That doesnt mean I wont carry this rifle into the field after some sort
of big game. On the other hand, it doesnt mean I will either. The 8mm-06 had its
time and place, and my rifle is a perfect example of both. It will do fine either in the
field or resting peacefully indoors, like any other artifact of history.
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