The .30-06 Springfield Cartridge Family
By Gary Zinn
"The .30-06 Springfield sits at the apex of the small bore, non-magnum, big game hunting cartridge pyramid. Loaded with suitable 150, 165, or 180 grain bullets, the cartridge is more than adequate for hunting all Class 2 game and most animals in the Class 3 category."
This is how I began a recent article on the 30-06 cartridge, The Forgotten 200 and 220 grain .30-06 Loads. This article is essentially an extension of that article, in which I explore the capabilities of the .30-06 and other cartridges based on the .30-06 case.
Specifically, I will compare high performance commercial loads for the cartridges in question with similar loads (bullet diameter, weight and type) in magnum cartridges. These comparisons will show that some of the .30-06 family cartridges are nearly as powerful as popular magnum cartridges of comparable caliber.
The viable commercial cartridges based on the venerable .30-06 case are, in time order of their commercialization, the .270 Winchester (1925), .280 Remington (1957), .25-06 Remington (1969) and .35 Whelen (1988). The .30-06 and .270 Winchester have long been two of the most popular hunting cartridges in the world. The other three have smaller, but loyal, groups of supporters within the hunting community, particularly in North America.
The 6.5mm-06 and .338-06 cartridges were commercialized by the A-Square company in the 1990s. Unfortunately, A-Square subsequently went out of business, leaving these cartridges orphaned, which effectively reverted them to wildcat status.
The 8mm-06 became somewhat popular as a wildcat cartridge after World War II, but it has never been commercialized. The 6mm-06 wildcat has been lurking in the weeds for a half-century or more, without garnering enough attention for anyone to commercialize it, although the excellent .240 Weatherby Magnum is similar in size and capability, being based on what is essentially a blown-out and belted .30-06 case.
Starting with the commercial cartridges, I selected typical, strong performing premium factory loads for each cartridge and for the magnum cartridges chosen for comparison. The first row of each data set identifies the cartridge, the brand of ammunition, the bullet weight and type (underlined), followed by the ballistic coefficient (BC), sectional density (SD) and the muzzle velocity (MV) as stated by the manufacturer. All MVs are from 24 inch barrels, unless otherwise noted.
The second row lists the +/- 3 inch maximum point blank range (MPBR) of the load (rounded to the nearest five yards), the G&S Online Killing Power Score (KPS) and the energy of the load, both at MPBR. Relevant summary comments follow the data presentation for each cartridge/load pairing.
.30-06 Springfield vs. .300 Winchester Magnum
.30-06 - Nosler Trophy Grade 180 grain AccuBond; BC .507, SD .271, MV 2750 fps:
.300 Win. Mag. - Black Hills Gold 180 grain Nosler AccuBond; BC .507, SD .271, MV 2950 fps:
The .300 Win. Mag. has a 20 yard (7%) longer MPBR, 13% more energy and a 13% higher KPS at MPBR than the .30-06 load.
.270 Winchester vs. .270 Winchester Short Magnum
.270 Win. - Winchester Deer Season 130 grain EPPT; BC .450, SD .242, MV 3060 fps:
.270 WSM - Winchester Deer Season 130 grain EPPT; BC .450, SD .242, MV 3275 fps:
The .270 WSM load has a 20 yard (7%) longer MPBR, 12% more energy and a 13% higher KPS (both at MPBR) than the .270 Win. load.
.280 Remington vs. 7mm Remington Magnum
.280 Rem. - Hornady Precision Hunter 150 grain ELD-X; BC .574, SD .266, MV 2925 fps:
7mm Rem. Mag. - Federal Fusion 150 grain SP; BC .509, SD .266, MV 3050 fps:
The 7mm Rem. Mag. has a 10 yard (3%) longer MPBR, 3% more energy and a 3% higher KPS (both at MPBR) than the .280 Rem. load.
.25-06 Remington vs. .257 Weatherby Magnum
.25-06 Rem. - Hornady Precision Hunter 110 grain ELD-X; BC .465, SD .238, MV 3140 fps:
.257 Wby. Mag. - Hornady Precision Hunter 110 grain ELD-X; BC .465, SD .238, MV 3240 fps:
The .257 Weatherby Mag. has a 5 yard (2%) longer MPBR, 5% more energy and a 5% higher KPS (both at MPBR) than the .25-06 Rem. load.
.35 Whelen vs. .338 Winchester Magnum
The only .35 bore magnums with which the .35 Whelen might be directly compared are the .350 Remington Mag. and the .358 Norma Mag. Both are nearly defunct, so I chose to compare the .35 Whelen with the .338 Winchester Mag.
.35 Whelen - Nosler Custom 225 grain Partition; BC .430, SD .251, MV 2725 fps:
.338 Win. Mag. - Nosler Custom 225 grain Partition; BC .454, SD .281, MV 2750 fps:
The .338 Win. Mag. load has the same MPBR, 4% more energy and a 4% higher KPS (both at MPBR) than the .35 Whelen load.
The .30-06 and the four commercial cartridges derived from it average 5% shorter in MPBR, 9% lower in energy and 10% lower in KPS at MPBR than the magnum cartridges with which they were compared. The .30-06 and its descendent cartridges are not quite as powerful as the magnums, but they are close. Of course, these results will vary somewhat, depending on the particular loads that are compared.
The 6mm-06, 6.5mm-06, .338-06 and 8mm-06
The 6mm-06 and 8mm-06 cartridges have always been wildcats (never commercialized), while the 6.5mm-06 and .338-06 are defacto wildcats, since they are orphaned commercial cartridges. I was not surprised, then, that there are very few, if any, production ammo loads offered for these cartridges.
This created a problem getting factory loads for performance evaluation, so I used representative reloading data for these four cartridges. I used reloading data for the comparison cartridges as well, because I feel this gives the best consistency for comparison. The loads are based on data in the Nosler Load Data website, unless otherwise noted. All MVs are in 50 fps increments, for convenience in making the calculations.
6.5mm-06 vs. 6.5 Remington Magnum and 6.5x55mm SE
6.5mm-06 - 130 grain Nosler AccuBond bullet; BC .488, SD .266, MV 3050 fps (average of 9 loads):
6.5x55mm SE - 130 grain Nosler AccuBond bullet; BC .488, SD .266, MV 2750 fps (average of 10 loads):
6.5 Rem. Mag. - 130 grain Nosler AccuBond bullet; BC .488, SD .266, MV 3100 fps (average of 9 loads):
The 6.5 Rem. Mag. load has a 5 yard (2%) longer MPBR, 4% more energy and a 4% higher KPS (both at MPBR) than the 6.5mm-06 load. The 6.5x55mm SE load is included to indicate that the 6.5mm-06 is definitely more powerful than the 6.5x55 (and the .260 Remington and 6.5 Creedmoor, which perform very much like the 6.5x55).
Note that data sources generally indicate that the 6.5mm-06 and the 6.5mm-284 Norma cartridges produce virtually identical ballistic performance with same-weight bullets. This is significant, because the 6.5-284 is more available, in terms of production rifles and commercial ammo, than the 6.5mm-06.
.338-06 vs. .338 Winchester Magnum and .338 Federal
.338-06 - 210 grain Nosler Partition bullet; BC .400, SD .263, MV 2650 fps (average of 6 loads):
.338 Federal - 210 grain Nosler Partition bullet; BC .400, SD .263, MV 2450 fps (average of 8 loads):
.338 Win. Mag. - 210 grain Nosler Partition bullet; BC .400, SD .263, MV 2950 fps (average of 8 loads):
The .338 Win. Mag. has a 25 yard (10%) longer MPBR, 21% more energy and a 21% higher KPS (both at MPBR) than the .338-06. The .338-06 is definitely not as powerful as the .338 Win. Mag., but it is a viable alternative for anyone who wants strong performance in a .33 caliber cartridge, with less recoil than a .338 Magnum.
As factory loaded, the .338 Federal is close to the .338-06 with a 210 grain Partition bullet. However, comparing average reloads, the .338-06 is a bridge cartridge between the .338 Federal and the .338 Win. Mag.
6mm-06 vs. .240 Weatherby Magnum and .243 Winchester
There is no load data for the 6mm-06 on the Nosler website. However, I found an adequate data set on the Load Data website, so this is what I used. I used Nosler data for the comparison cartridges.
6mm-06 - 100 grain Nosler Partition bullet; BC .384, SD .242, MV 3150 fps (average of 12 loads):
.243 Win. - 100 grain Nosler Partition bullet; BC .384, SD .242, MV 3000 fps (average of 12 loads):
.240 Wby. Mag. - 100 grain Nosler Partition bullet; BC .384, SD .242, MV 3200 fps (average of 9 loads):
The .240 Wby. Mag. load has a 5 yard (2%) longer MPBR, 3% more energy and a 3% higher KPS (both at MPBR) than the 6mm-06 load. Both are a step-up in power compared to the .243 Winchester.
8mm-06 vs. .325 WSM and 8x57JS Mauser
The Nosler Load Data site lists only three loads for the 8mm-06. I found a larger data set in the Speer Reloading Manual #14.
8mm-06 - 200 grain Speer spitzer SP bullet; BC .411, SD .274, MV 2600 fps (average of 8 loads):
8x57JS Mauser - 200 grain Speer spitzer SP bullet; BC .411, SD .274, MV 2600 fps (average of 6 loads):
.325 WSM - 200 grain Speer spitzer SP bullet; BC .411, SD .274, MV 2900 fps (average of 9 loads):
The average 8mm-06 and 8x57mm JS Mauser reloads are a dead tie. The .325 WSM load has a 25 yard (10%) longer MPBR, 22% more energy and a 22% higher KPS (both at MPBR) than the 8mm-06 and 8x57 Mauser loads. A different, but revealing, comparison is that the 8mm-06 and 8x57 loads are very close in power to the 180 grain .30-06 load listed above.
There is something odd about the performance of the 8mm-06. I have seen information indicating that the 8mm-06 case has about 15 percent more capacity than the 8x57 case. However, all of the load data sources I reviewed consistently show that maximum MVs of the two cartridges are nearly identical with the same weight bullets. Any differences usually indicate an advantage to the 8mm-06 of no more than 50 to 100 fps MV. It puzzles me that the 8mm-06 is not loaded to give significantly faster MVs than the 8x57.
I think it is also notable that the .325 WSM load is only slightly more powerful than a 200 grain .30-06 load. The European 8x68mm and US 8mm Remington Magnum cartridges are more powerful than the .325 WSM, but have very little popularity in North America.
As I see it, the commercial cartridges in the .323 bore slot suffer from being sandwiched between the .30-06 and .300 Win. Mag. on one side, and the .338 Win. Mag. on the other. None of the 8mm cartridges do anything that the much more popular .30 or .33 caliber cartridges cannot, so the 8mm cartridges are pinched out of the market when rifle and ammunition makers are deciding where to concentrate their production and marketing efforts, and also when hunters are choosing a cartridge for use on heavy game.
The .30-06 and .270 Winchester provide dominant ballistic performance among non-magnum cartridges in their respective bore classes, so there is no mystery why they have been very popular hunting cartridges for a long time. The .280 Remington, .25-06 Remington and .35 Whelen occupy less prominent positions in the hunting cartridge hierarchy, but are capable of excellent performance.
Among the .30-06 based wildcats, the 6.5mm-06 and .338-06 exist in a state of limbo, with no commercial support since the A-Square company closed. This is unfortunate, because both cartridges have performance that bridges substantial gaps between established non-magnum and magnum cartridges in their respective bore sizes.
The 6mm-06 and 8mm-06 are probably destined to remain as they are, strictly wildcats, with no real prospect of ever being commercialized. There is no apparent rationale for another standardized 6mm or 8mm cartridge, whatever its origins.
Copyright 2018 by Gary Zinn and/or chuckhawks.com. All rights reserved.