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Dogman
18th August 2011, 12:16 PM
One of America’s most popular cartridges is the .243 Win., however, the 6 mm Rem. and .240 Wby. Mag. actually deliver better ballistics.

By John Barsness

http://www.americanrifleman.org/Webcontent/images/2011-8/20118994724-201183113920-ar-6mms-2_m_2.jpg

While the number of commercial center-fire rifle cartridges continues to grow, the line-up of the most popular ones, chambered by just about every manufacturer, has remained static since the 1960s. That list includes the .223 Rem., the .22-.250 Rem. (http://www.americanrifleman.org/articles/handloading-22-250-rem/), the .243 Win., the .270 Win., the 7 mm Rem. Mag., the .308 Win., the .30-’06 Sprg. and the .300 Win. Mag (http://www.americanrifleman.org/ArticlePage.aspx?id=1767&cid=31).

With one exception, the cartridges on the list fall into three categories: ancient standbys that never allowed another other cartridge to play in their house (the .270 Win.); commercial consolidations of old ideas (the .22-.250 Rem., 7 mm Rem. Mag. and .300 Win. Mag.); or ex-military numbers that work darn well for sporting purposes (the .223 Rem., .308 Win. and .30-’06 Sprg.). The .243 Win. is none of the above.

Before the .243 Winchester’s appearance in 1955, the niche of “varmint/deer cartridge” was filled by the .250 Savage and .257 Roberts. They will do anything the .243 can, plus shoot bullets up to 120 grains, rather than the 105 grains or so possible with the .243. Those 15 grains of bullet weight are why daring rifle manufacturers sometimes still chamber the .250 Savage or .257 Roberts, at least for now. It doesn’t take long to fill the limited demand of geezers and obsessive-compulsives. The typical shooter just buys a .243 Win. rifle.

This is true from America to Africa. I’ve seen .243s in the hands of Inuits in the Arctic—who carry one as their “big” rifle when after polar bear and the larger seals—and South African biltong hunters, those who cull antelope from springbok to kudu for the commercial jerky market. In my native Montana the .243 Win. is the number-one choice for a first big-game rifle, the cartridge kids use on pronghorn and deer (and sometimes elk) before they matriculate to really “big” ones such as the .270 Win.

I have a soft spot for the .243 Win., since the little cartridge cured a cringing flinch caused by the aluminum buttplate on a Savage 99 chambered for the “mild” .308 Win. As John Wayne observed about Glenn Campbell’s Sharps in “True Grit,” that 99 was “too much gun” for a skinny 14-year-old. A few years later a .243 Win. finally put the flinch to rest.

Still, the only reason the .243 Win. made the list is because of Warren Page, the long-time shooting columnist for Field & Stream magazine. Page went on a 6 mm binge in the early 1950s, using his .24-cal. wildcats to kill many game animals worldwide. Afterward he wrote about how the 6 mms simply worked better than those plodding, old .25s.

There were far fewer hunting and shooting magazines in those days, and Field & Stream was the biggest. A lot of people bought Page’s line, including some decision-makers at Remington and Winchester. In 1955 Remington introduced the .244 and Winchester the .243.

The .244 Rem. was essentially the .257 Roberts necked down, and the .243 Win. was the .308 Win. necked down. The .244 featured a 75-grain bullet at 3,500 fps and a 90-grain bullet at 3,200 fps, while the .243 featured an 80-grain bullet at 3,500 fps and a 100-grain at 3,070 fps. They were like fraternal twins who graduated from different high schools.

The .243 Win. soon took the lead in the battle of the 6 mms. Most theorists suggested this was due to the 90-grain “heavy” bullet of the .244. As so many claimed they “knew,” bullets weighing less than 100 grains didn’t work on deer. (Some real old-timers claimed the original 87-grain load for the .250 Savage worked like a death-ray.)

Consequently, in the early 1960s Remington changed the .244’s name to the 6 mm Rem. and started loading a 100-grain bullet at a reported 3,190 fps, more than 100 fps faster than the 100-grain, .243 Win. The 6 mm Rem. sold well at first, partly because Remington had just revamped its homely Model 721/722 rifle into the modern Model 700.

Shortly thereafter Winchester reworked the Model 70, and many shooters didn’t like it. Even then the .243 Win. had such a big head-start that the 6 mm Rem. never could catch up. Today almost nobody chambers the 6 mm Rem., while its counterpart is a world standard.

An unfortunate aspect of the modern capitalistic system is that the best dog doesn’t always win. Sometimes it’s the dog with the best marketing strategy, whether deliberate or accidental. The entire 6 mm phenomenon of the 1950s displaced two perfectly fine .25-cal. cartridges—and then, according to many experts, the wrong .24 cal. won.

To those men who obsess over microscopic details, the 6 mm Rem. is plainly superior to the .243 Win. The 6 mm Rem. holds about two grains more propellant and has a longer neck and sharper shoulder, all considered advantages in the nit-picky world of cartridge design.

The deficiencies of the .243 Win.’s sloping shoulder and short neck are real. My first .243 Win. was a cross-breed of the .24 wars, a Remington Model 700 BDL. Not long after I started handloading for the 700, my reloads started showing signs of pressure-distress, despite my using a load that worked fine at first. Eventually I traced the cause to the case necks thickening through several loadings and cured it with an inside-neck reamer. This happens quite a bit with .243 Win. brass, but isn’t a problem in the 6 mm Rem.

Eventually many laboratory ballisticians also found the .243 Win. to be somewhat quirky, a discovery made when the industry started switching from copper-crusher to piezoelectric pressure-testing equipment during the 1970s and ’80s. Copper-crusher testing provides only a maximum pressure, though other information can be extrapolated from the result. Piezoelectric equipment provides a moment-by-moment look at the pressure curve.

Piezoelectric testing revealed that certain cartridges and loads resulted in rather strange pressure curves, often with unexpected detours. The .243 Win. was one of these oddballs. I’ve visited several ballistics labs and interviewed their technicians through the years. Many have volunteered information about the cartridge’s quirkiness, particularly with bullets in the 100-grain range, and especially after the chamber throat gets slightly worn.

During this same period, test-barrels were shortened. For decades the standard length was 26 inches, but by the 1960s few commercial rifles had barrels that long—and the trend was downward. Both the .243’s pressure quirks and shorter barrels resulted in a severe drop in the listed muzzle velocity of the 100-grain factory load, from 3,070 fps in 1955 to 2,960 fps. in 1980, both chronographed from a 24-inch barrel.

Since most .243 Wins. now have 22-inch barrels, factory loads usually chronograph around 2,900 fps. This is slower than the 100-grain factory load in the 6 mm Rem., the same velocity as the (now dead) 100-grain, .257 Roberts factory load, and almost as slow as 100-grain, .250 Savage factory loads. The Wonder Cartridge that supplanted the .25s now has essentially the same ballistics.

None of this is obvious to the average shooter, and it shouldn’t be. Even those handloaders sensitive to every nuance of a brass case can’t perceive the pressure quirks that piezoelectric pressure machines pick up. And there’s really no difference in how the .243 Win., 6 mm Rem., .250 Savage and .257 Roberts kill varmints or deer. Some might argue the point. Go ahead, talk to a sheet of paper—but I’ve taken dozens of deer with those four cartridges. As a result, the .243 Win. continues blithely onward, the hottest-selling factory cartridge between the .22-.250 Rem. and .270 Win.

http://www.americanrifleman.org/articles/other-6-mm-ammunition-2/

Gaillo
20th August 2011, 09:53 AM
I've done a lot of work with the .243 Win, and in my opinion it really is a magnum-class cartridge. Ballistically, it's one of the flattest shooting, if not THE flattest shooting intermediate cartridges, although it doesn't buck the wind as well as larger bore 6.5mm and 7mm cartridges of similar size.

Oh... and as to the claim that you need 100+ grain bullets for deer, that is COMPLETE BS... 85 grain Gamekings from a .243 is one deer-slaying mofo! ;)

As for the .243 Weatherby Magnum... no thanks. I don't like buying barrels THAT much! ;D

My favorite 6mm option, and very definitely the next gun I'll be buying, is something called the 6X45... basically a .223 Rem. necked up to 6mm. Relatively unknown in America, it's EXTREMELY popular among African bush hunters... light recoil, long barrel life, plentiful brass, miserly powder usage, and lightweight short-action rifle options make it a real winner in my opinion. Plus, you can re-barrel your AR poodle-shooter with it and use the same bolt, magazines, and action!

SWRichmond
25th August 2011, 01:57 PM
But then, on the other hand, a .308 210 Berger VLD at 2800 fps muzzle still has over 1100 ft-lbs of energy at 1000 yards. Why screw around with this little stuff?

Gaillo
25th August 2011, 09:11 PM
But then, on the other hand, a .308 210 Berger VLD at 2800 fps muzzle still has over 1100 ft-lbs of energy at 1000 yards. Why screw around with this little stuff?

Uhhh... resistance to wind drift (THE hardest factor to compensate for among long-distance shooters...), and FLAT trajectory (not as affected by minor variations in powder charge, bullet weight/diameter/bearing surface length, case volume differences, etc. etc. etc.)

SWRichmond... exactly HOW much long-distance shooting have you actually done? I'm not aware of a SINGLE serious competition long-range shooter (other than military nostalgia "camp X" meatheads...) currently using a .30 Caliber ANYTHING - they've pretty much ALL moved to 6mm, 6.5mm, or 7mm variants.

6mm is no slouch... although I personally am of the opinion that something between 6.5mm or 7mm is the ULTIMATE for intermediate military-tasked cartridges, so don't assume I'm in love with the 6! However, at the same time, please don't make the mistake in thinking the .243 Win. is "Grandma's deer rifle" - plenty of NWO thugs will fall to its superior ballistics before this thing is through - of that I have no doubt at all!

If I could pick ONE currently available semi-common cartridge to fulfill the long-distance military role I'm speaking of, it would be the .260 Rem... probably THE pinnacle of .308 Win. cartridge variant design, and the ballistic twin to the famous (and rightly so...) 6.5x55 Swedish Mauser. For those seeking an ARPoodleShooterCompatible(TM) cartridge option (important to some, not so much to me...) I would suggest that the best thing currently out there is the very impressive 6.5 Grendel.

SWRichmond
26th August 2011, 05:08 PM
"I'm not aware of a SINGLE serious competition long-range shooter (other than military nostalgia "camp X" meatheads...) currently using a .30 Caliber ANYTHING"

Perhaps you are referring to "service rifle"? Do me a favor, go to a service rifle match, or better yet to an Appleseed match, and tell them you think they're meatheads, or even more fun, "not serious."

Obviously, you have never heard of "F-T/R," which is almost exclusively shot with .308 Win, and which is a very very popular long range discipline in which thousands of very serious competitors participate. I can almost guarantee you that they're not meatheads (well, most of them). I shoot F-T/R, and F-Open with a .300. I don't mind the recoil, nor do I find it tiring. I am finicky about my equipment in keeping it practical. The .260 Rem is ballistically attractive. I don't have time for a third long range rifle.

Based on your lack of knowledge, maybe I should ask you how much long range YOU'VE shot? Blowhard.

Edit: I came back to pile on a little more. Obviously, you have never heard of Palma, which is shot almost exclusively with iron-sighted .308 Win. rifles at 800, 900, and 1,000 yards, another very serious international long range rifle discipline that you've apparently never heard of.

NRA Fullbore Prone Rifle is also shot almost exclusively with .308 Win. and is shot at long range.

And then there's this, from the NRA highpower rulebook: "6.4 Distances—Matches are commonly fired at ranges of 100, 200, 300, 500, 600, 800, 900 and 1000 yards."

Can you be any blow-hardier than you just were?

Gaillo
27th August 2011, 11:57 AM
So... you blew hard about the "small stuff" that F-Class shooters, people like Dave Tubbs, Zedicker, etc. use. after having abandoned .30 cartridges.
I returned the blow hard about the .30's, throwing in a meathead comment.

Who's the bigger "blow hard" here? Who knows... we're both obviously opinionated, and blowhardiness has been committed by us both.

Let's forget it and move on... it's getting downright uncivil! :(

SWRichmond
19th September 2011, 08:52 AM
Like I said, at 1,000 yards my .300 still has over 1,000 ft-lbs of sinew-penetrating, organ-destroying, life-ending energy. Let me see you do this with a stupid whimpy-ass 6mm pussy gun:

http://www.youtube.com/watch?v=L48Eok5hQZo

Dogman
19th September 2011, 09:05 AM
So... you blew hard about the "small stuff" that F-Class shooters, people like Dave Tubbs, Zedicker, etc. use. after having abandoned .30 cartridges.
I returned the blow hard about the .30's, throwing in a meathead comment.

Who's the bigger "blow hard" here? Who knows... we're both obviously opinionated, and blowhardiness has been committed by us both.

Let's forget it and move on... it's getting downright uncivil! :(


Like I said, at 1,000 yards my .300 still has over 1,000 ft-lbs of sinew-penetrating, organ-destroying, life-ending energy. Let me see you do this with a stupid whimpy-ass 6mm pussy gun:

http://www.youtube.com/watch?v=L48Eok5hQZo

Got to love these gun dis-cussing exchanges!

1088

1089

undgrd
19th September 2011, 09:52 AM
300 Blackout making a lot of noise recently. Should check out that cartridge.

http://www.300aacblackout.com/
http://www.300aacblackout.com/images/300BLK-556Pic2.jpg

Barrel
9 in (230 mm) barrel
16 in (410 mm) barrel

Cartridge
300 AAC Blackout, 123 gr MC 2,130 ft/s (650 m/s)
300 AAC Blackout, 123 gr MC 2,280 ft/s (690 m/s)

Velocity
2,130 ft/s (650 m/s)
2,280 ft/s (690 m/s)

Energy
1,238 ft·lbf (1,679 J)
1,420 ft (430 m)-lb

SWRichmond
19th September 2011, 01:09 PM
I'll break up this urinating olympiad contest and add that I have a .243WSSM in a Win model. It's a real killer. I was a wally-world one day and they had the ammo on clearance for 10.00 a box and bought nearly 500 rnds for it. Here's some more info on it here..http://en.wikipedia.org/wiki/.243_Winchester_Super_Short_Magnum

That's probably about how much barrel life you'll get...I wouldn't bother buying reloading dies.