This popular calibre started with the .270 Winchester, but now there's two larger cartridges in this category which offer higher velocity, increased hitting power and a flatter trajectory.
THE .270 WINCHESTER has been around since 1925. It continues to sell steadily, and every year sees use on everything from goats and pigs to elk and moose, from springbok to eland and even big brown bears. Rifles for the cartridge are made in just about every country in the world, so is the ammunition. Probably more fine classic custom rifles have been made in this country and the U.S.A in .270 Winchester calibre than any other, except possibly the .30-06.
As a youngster I was an avid reader of Jack O'Connor's articles in Outdoor Life. O'Connor spent most of his writing career working to popularize the .270 Winchester. In his opinion it was the best allround cartridge ever designed for all North American big game and African plains game. The dogmatic and rather acerbic Arizona professor of English took little notice of the .270 Weatherby when it appeared 20 years later, nor do I think he would have forsaken his first love for the new .270 Winchester Short Magnum (WSM). Being that rarest of beings, a down to earth, scupulously honest reporter where guns and ammo were concerned, Jack was a hard man to impress; he never was able to muster much enthusiasm for every new cartridge that came along or see pie in the sky.
O'Connor praised the .270 lavishly for 50 years, and it was his writings that influenced me to buy as my first bolt-action centrefire rifle, a Brno ZG47 in .270 Winchester nearly 60 years ago. Since that day I've never been without at least one rifle in that calibre, but today, I also own a .270 WSM and .270 Weatherby Magnum.
I soon discovered that because of its flat trajectory, high velocity, good accuracy and mild 15 ft/lbs of recoil, the .270 is the easiest standard cartridge to make well-placed hits with on game at long and uncertain ranges. For mountain hunting I followed O'Connor's advice and sighted-in my Brno .270 to put a good 130gn spitzer bullet 3 inches above line of scope at 100 yds. The bullet then landed 4ins. high at 200 yds., zeroed at 275 yds. and dropped about 2 ins. at 300. That gave me a pointblank range of almost 350 yds., as the bullet will not rise or fall more 4ins. from the line of aim up to that distance.
In the field I discovered that if a deer was well over 300 yds. away and I held on his backbone, I could score a solid hit out to 400yds. The drop between 275 and 400 yds. with sleek 130gn spitzer bullets like the old Norma, Hornady, Sierra and Speer was 15 ins.
I began handloading for my .270 with a Cartridgemaster press from Bruce Hill and a Simplex 7/8x14 die set from Bill Marden. At first I used Norma 204 powder, but soon changed over to slower-burning H4831, a surplus powder that cost the equivalent of $6 a can back in those days! In my Brno ZG 47 with 24 in. barrel and 1:10' twist 60gn of H4831 in Norma cases delivered a strong3,160fps, the same muzzle velocity that the Norma factory claimed.
Later when I started hunting red stag I worked up a load with the 150gn bullet and 58gn of H4831 that generated 2,950fps. With a bullet having the sectional density of a .30 calibre bullet weighing around 200gn, my .270 yielded some pretty impressive ballistics. The extra weight and excellent sustained velocity of the 150 grainer out at the longer ranges, made the .270 even better for big game.
During the years when I used the .270 for pro roo shooting, I wore out eight barrels in my Brno. I have hunted with it all over Australia and in America. I have shot a few truckloads of goats and pigs with the .270 and a number of deer. The last big animals I took with the .270 were a couple of scrub bulls that each succumbed to a single 130gn Barnes X. A very satisfactory cartridge the .270 Winchester, one that in the hands of a good shot will handle most big game, yet one that is pleasant to shoot.
Thousands of hunters have found that if a faststepping 130gn .270 bullet is placed in the heart/lung area, it almost always spells instant death for an animal the size of a red stag or even elk and moose. For my own part, I like the 150gn bullets better for their extra penetration which is an advantage on larger animals.
Since the end of World War II we've seen the introduction of many new long-range cartridges, such as the .264 Win Mag, that many predicted would spell the doom of the .270 Winchester, but so far none have come close. Roy Weatherby issued a serious challenge when he introduced his .270 Weatherby Magnum in 1945. It was 200fps faster than the .270 Win., but many hunters did not regard this as a significant advantage, preferring the lighter recoil and cost of the .270 Win.
If we discount the .280 Remington, the most serious challenge issued to the .270 Win. came in 1962 when Remington introduced the belted 7mm Rem Mag. which enjoyed a brief period of popularity which soon faded out. When Jack O'Connor died in 1978, a good many shooters predicted that the .270's popularity would fade, but 30 years later, the .270 Win. is still among the first three on the list of RCBS list of rifle die sales. Last I heard the 7mm Rem Mag ranked 6th and the .280 Rem. 15th. So clearly there is something that has kept the .270 Win. among the top sellers.
The light recoil of the venerable .270 is of great importance since it allows it to be made up into a rifle that is portable, handy and reltively light, as the mountain hunter carries a rifle a lot more than he shoots it. Except for some hairychested gun writers, most of us shoot rifles of light recoil better than we do rifles of heavy recoil, and also because the mountain hunter often has to shoot from odd and uncomfortable positions from which he may be hammered by heavy recoil or even be kicked off a steep mountainside.
The ideal mountain rifle has a 550mm barrel, which although permitting fairly good ballistic performance with the .270 calibre, is much too short for small-calibre magnums.
Although recently, some of the .270 Winchester's thunder has been stolen by the new .270 WSM, which packs a slightly greater wallop, this oldtimer is still a terrific long range killer of deersize game - much better in my opinion than the newer 7mm-08, and .280 Rem.
So how does the .270 really compare with the new .270 WSM?
Let's forget all the bulldust and present an objective comparison of the two .270s. The new .270WSM looks to have a real edge with 200fps more velocity and 15 percent more energy than the standard .270 Winchester with all equivalent bullet loadings in a 12mm shorter case that will work through a short action. Of the four short magnums, the .270 WSM has gained the lion's share of attention from the shooting media. Undoubtably, this is because some of the original .270's popularity has rubbed off on it.
The .270 Win. is simply the .30-06 case necked down; ìthe other .270,' Roy Weatherby's .270 Magnum started life as wildcat in 1943 on a necked-down, sharp-shouldered .300 H&H case. The new .270 WSM is based on the original short, fat, beltless .300 WSM case and has the same abrupt 35 degree shoulder which provides precise headspacing. Moreover, the improved efficiency of propellant burn in the shorter-fatter case is what allows the WSM to achieve higher velocities with equivalent bullets than its longer case antecedent - with less powder mass. The .270 WSM is also credited with enhanced accuracy due to improved ignition and burn uniformity.
The .270 WSM is aso claimed to provide less absolute recoil from smaller powder charge weights. Just how this comes about puzzles me, since charges in my .270 Win. run from 55 to 60 grains of powder while in my .270 WSM they run from 62 to 68 grains! My shoulder tells me that there's very little difference. Calculations vindicate me with 18.5 ft/lb for the .270 WSM and 17.5 ft/lb for the .270 Winchester when both are loaded to top speed with 130gn bullets.
The three .270 calibre cartridges – L to R: .270 Winchester, .270 WSM and .270 Weatherby Magnum. Each one should be handloaded with a premium big game bullet for the best results.
While we are in the debunk stage, let's also deal with the supposed short-action advantage due to a speedier 12mm shorter bolt travel. Assuming the shooter works the bolt without taking the rifle down from his shoulder, he still has to recover from the recoil and adjust his aim before he can take a followup shot. Hence, I cannot see any practical advantage to having a 12mm shorter bolt throw. Nor are most of the short action rifles chambered in .270 WSM any lighter than their .270 Win. counterparts. My gut feeling says: make ëem lighter and you make ëem less effective.
I've been hunting with the .270 Win. much longer than the .270 WSM, but I've killed enough game in the past 5 years with my new Model 70 .270 WSM to know what to expect from it in the field. At the risk of upsetting some of those who have traded their old rifles in .270 Win. for a new rifle in .270 WSM, I darned if I can see any real difference in their performance. Everytime I landed a good bullet in the heart/lung area with either cartridge, it was all over bar the skinning.
Which raises the question: Is the .270 WSM as much fasterthan the .270 Win as the ballistic tables (and over enthusiastic gun writers) would have us believe?
My three .270 rifles - Win. WSM and Weatherby - all have 610mm barrels, but the effective barrel length of the .270 WSM is about 1/2 inch longer than in .270 Win. because of its shorter case. Likewise, my .270 Weatherby (a rechambered .270 Win) loses a bit of bullet travel because of the freeboring, but can take heavier loads. However, these are very minor differences. Maybe the additional 12mm of rifling may give the .270 WSM a slight edge of 25 fps, but I wouldn't bet on it. Several other factors enter into ballistic calculations.
Most comparisons are carried out using standard .270 Win. loads which give a 130gn bullet 3,060fps and a 150-grainer 2,850fps, but this is hardly fair as there are premium loads that show the original .270 to better advantage. Winchester Supreme ammo lists the 150gn Partition Gold at 2,930fps and that bullet is still travelling at 2,051 fps and delivering 1,402 ft/lbs at 400 yards. The .270 WSM 150gn Power Point bullet starts out at 3,150fps and has 2113 fps and 1,487 ft/lbs left at 400yds. Hardly an earthshaking difference, and the Partition Gold is far superior to the Power Point on big game. In adition, I've never chrono'd a .270 WSM factory load with the 150gn bullet at 3,150 fps and my handloads are struggling to attain 2,930fps!
Another instance: Hornady's Light Magnum load drives the 130gn Interbond bullet at a sizzling 3,215fps and still has 2,406 fps and 1,671 ft/lb at 400yds. By comparison, Winchester Supreme .270 WSM launches the 130gn Ballistic Silvertip at 3,275fps and at 400yds. has 2,408fps and 1,673 ft/lb. No difference at all! But in my experience the Interbond is far and away the better big game bullet.
In order to live up to published muzzle speeds, a .270 wSM needs a 610mm barrel since there is considerable loss in a shorter barrel. A rifle with a 550mm barrel I tested chrono'd at 3,150 fps with the Supreme 130gn BST and 3,055fps with the 130gn AccuBond.
Handloaders have struck difficulties with the .270 WSM too. A good many found that cases were difficult to chamber after once-firing factory loads racking up 63,000 PSI had been neck-sized only. Full length sizing doesn't always make cases easy to chamber either. For my own part, I am happy to settle for reloads that drive the 130gn bullet at 3,200fps, the 140gn at 3,150 and 150gn at 2,980fps. A very effective big-game load drives the 160gn Lapua Mega bullet at 2,940fps for hunters who want more bullet weight for their particular quarry. My reloads generate slightly less pressure than the factory fodder, but I still full-length resize my cases every time.
The .270 WSM bears the same relationship to the .270 Win. as the .300 WSM does to the long-action .300 Win Mag. - slightly more powerful and more ballistically efficient in a short-action rifle. No doubt but that the .270 WSM represents a major high power rifle ammunition development. But I wouldn't go so far as to say that its basic design parameters are likely to make the long-action .270 cartridges obsolete, because it cannot fullyequal the performance of the largest case when the heaviest bullets are used, which brings us to the ultimate .270 - the powerful .270 Weatherby Magnum.
With certain handloads this excellent cartridge actually outdoes some of the big 7mm Magnums with its heavier bullet loadings for long range wapiti shooting. With modern slow powders the .270 Weatherby is not overbore capacity and at extreme ranges is one of the finest calibres ever developed. Almost 10mm of freebore throating allows free bullet travel before the engraving process of the lands starts, dropping initial resistance and pressures, thus allowing more powder to be burned to give a slight velocity increase.
As far as medium big game is concerned, the .270 Weatherby Magnum is one of the finest long range cartridges ever designed. Consider the effectiveness of the .270 Winchester for this kind of shooting, then flatten the trajectory by adding another 200 fps or so for all bullet weights. The .270 Weatherby not only shoots flatter but has increased striking energy at long range. But where it really shines is with bullets weighing 150 and 160 grains.
Weatherby factory ammo drives a 100gn S.P bullet at 3,760fps; a 130gn Barnes TSX at 3,400fps; 130gn Partition at 3,375fps; 140gn Ballistic Silvertip at 3,300fps; 140gn AccuBond at 3,320fps; and 150gn Partition at 3,245fps. The 140gn and 150gn loads deliver around 2,000 ft/lbs of wapiti-killing energy at 400yds.
The .270 Weatherby is an easy cartridge to handload, having no hidden vices. Powders I've found most useful in it are AR2209 (3,572 fps with 110gn bullets), AR2213sc, Re-22, Re-25 (3,400fps with the 130gn), and AR2217 (3,050fps with the heavy 160 Lapua). Although most rifles for the .270 Weatherby have 650mm barrels my Model 70 Winchester has a 610mm length which I find handier in the hunting field.
When it was available as a component bullet I used the 150gn Partition Gold with great success on chamois, fallow bucks and a wapiti bull in N.Z Is the .270 Weatherby an African cartridge? My answer is an unequivocal yes - just as long as you use heavy, controlled-expansion bullets - tough ones such as Barnes TSX, Swift A-Frame, and Speer Trophy Bonded.
I took handloads to Namibia and with my Leupold 2.5-8x scope zeroed at 300yds, I used the 130gn TSx to cull seven springbok at very long ranges from 250 to over 400 yds. It also accounted for red hartebeest, gemsbok and blesbok at around 150yds, stopping each one dead in his tracks. Terminal performance on an adrenaline-charged black wildebeest at a good 300yds was equally as spectacular. Both bullets worked well, showing plenty of weight retention and deep penetration not only on side-on shots, but front-angled shots or rear-end raking shots. By my rule of thumb, the .270 Weatherby with strong 150 and 160gn bullets is adequate for Africa's largest antelopes including kudu and eland. It's not a dangerous game calibre, but would be lethal medicine for leopard shot from a blind.
Gemsbok and springbok in Namibia's Kalahari desert terrain are often along range proposition. On a plains game hunt the most versatile bullet weight is 150 grains loaded to top velocity, since there's no practical difference in trajectory between 130 and 150gn bullets of similar configuration. Having higher sectional density, the 150-grainer retains its velocity better over the long haul, making it just as flat shooting as the 130 and 140gn weights for all practical purposes. Zeroed for 300yds, the 130 and 150gn bullets land within 0.2 inches of each other at 300 and 400yds, which means there's no difference in trajectory.
A major difference, however, is that the 150-grainer delivers more energy and momentum at the longer ranges; therefore it hits harder and penetrates deeper, making it a better choice for the larger African antelopes.
This is the way I sum it up: if you like the .270 calibre and yearn for true magnum performance, the .270 Weatherby may not be the only choice, but no other shows flatter trajectory or is harder hitting over long ranges.
This article was first published in Sporting Shooter, May 2009.