Get Ready for the .20-Caliber

This new cartridge may be the ultimate varmint round.

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Oh, no! Not another new caliber. Don’t we have enough already? Well, maybe not. In recent times gun and ammo makers have kept gun writers dancing and readers dizzy with an unprecedented outpouring of new cartridges. Of course, any new cartridge is juicy grist for the gun writer’s mill, but let’s face it, we’ve milked that old cow until there’s not much cream left. Just count the new .30-caliber rounds introduced in the past few years and you’ll run out of fingers. And then there are all the 7mm’s, .33s, .375s and .416s being endlessly reborn in cartridge cases that are stretched, shrunk, fattened, and liposuctioned. Still, there remain only a handful of basic calibers.

There are a couple of reasons why truly new calibers come along so rarely. One is that gunmakers are as slow as a cat eating a grindstone when it comes to developing new bore sizes. The other is that we, the shooting public, are thoroughgoing Puritans about our calibers and tend to burn new ideas at the stake. But sometimes a completely new caliber offers such exciting possibilities that it can’t be ignored. So get readyhere comes the .20!

Why the .20?
Okay, your first question is: “What is the .20 for?” And next: “What does it do that existing calibers don’t?” Primarily the .20 is a varmint caliber, and what it does better than other calibers can be answered by comparing the best and worst features of calibers on either side of it: the .17 and .22 centerfires. Probably the most attractive feature of the .17 Remington and the various .17-caliber wildcat variations is that they are a delight to shoot. Recoil is so nearly nonexistent that if it were not for the mild muzzle blast you’d think you were pulling the trigger on an empty chamber. Since the rifle remains motionless, you see all the action through the scope, whether it’s holes appearing in a target, a coyote doing a nosedive or a prairie dog losing a grip on his parts. On the negative side, the .17 tends to be finicky about its ammo. Bore-fouling and subsequent loss of accuracy are ongoing problems with some rifles, and the little bullets are slaves to a wayward wind. Despite its 4040 feet per second (fps) muzzle velocity, the .17 Remington bullet gets carried nearly 8 inches sideways at 300 yards by a gentle 5 mph puff of crosswind. By comparison, a factory-loaded .22/250 bullet weighing 55 grains and pushed out the muzzle at only 3680 fps is nudged a tad over 5 inches by the same crosswind. That three-inch difference is vital to varmint shooters because it’s about the chest span of a standing prairie dog.

The various .22-caliber centerfires, most notably the .22/250 Rem. and .220 Swift, which are usually loaded with 50- or 55-grain bullets, are less sensitive to the wind. However, in launching these bullets at velocities of 3600 fps and faster, there is a considerable amount of rifle movementnot hard recoil, of course, but enough to jump the scope so you can’t enjoy the action. A few years ago I was determined to have a .22/250 heavy enough to lie still on a rest when fired and ended up with a pudgy 15-pounder.

When you total up the good features of .17s and .22s, and toss out the bad, you come to the conclusion that a bullet of some 33 to 36 grains of weight, moving at 3800 fps, or faster, would be about perfect. But a bullet in that weight range would be too heavy for a .17 and too light for a .22, meaning that a bore size about midway between the twoa .20 caliber–is, like Baby Bear’s bed in Goldilocks, just right!

So if the .20 is so logical, why hasn’t it already become the darling of varmint shooters? Explaining why gun people fall in love with one cartridge and snub another is as fruitless as trying to catch a falling star. But the main reason the .20 has yet to win the fancy of shooters is because it hasn’t been available. Actually, during the late 1960s, the .20 had 15 minutes of fame when Rington announced its 5mm rimfire. With a 38-grain bullet at 2100 fps, the Remington was a passable varmint round inside 200 yards and earned considerable respect among turkey hunters. The rifles weren’t much, however, and unsolvable problems prompted Remington to drop them, along with 5mm ammo (which now, by the way, sells for about $50 per box, if you can find it). [pagebreak] **A Star Is Born **
Following Remington’s ill-fated experience with the 5mm rimfire, the .20-caliber concept again faded into obscurity and likely would have remained there had the folks at Douglas Barrels not been once again bitten by the .20 bug. A.L.

|||||| |—|—|—|—|—| |.20 TNT Ballistics 33-grain Hornady T-Max bullet| | Range (yd.)| Velocity (fps)| Energy (ft.-lb.)| Trajectory (in.)| Wind Drift (in.)*| | 0| 3950| 1143| -1.5| 0| | 50| 3632| 966| 0.6| 0.1| | 100| 3336| 816| 2| 0.6| | 150| 3061| 686| 2.6| 1.4| | 200| 2802| 575| 2.3| 2.6| | 250| 2558| 479| 0.9| 4.1| | 300| 2326| 396| -1.8| 6.2 (* 5 mph crosswind)| Gardner, the longtime head man at Douglas, had championed the .20 caliber and considered it too good to be allowed to die. This ideal was passed along to his son, Tim, now president of Douglas, who passed the fever on to me some four years ago when he called with the news that Douglas was again making .20-caliber barrels. Not only that, but Walt and Eunice Berger, of benchrest bullet fame, were making pretty little .20-caliber bullets.

“What case would you use if you were designing a .20 wildcat?” Tim asked. A menu of possibilities flashed through my brain like numbers in a slot machine, then came to a stop on the .223 Remington. The powder capacity would yield at least 3800 fps with 36-grain bullets. There are plenty of actions already adapted to the .223 case, which would make building a rifle simple. And cheap .223 brass is available by the bushel. All in all, it was a wildcatter’s dream. “I’d go with the .223 case simply necked down to .20, with the shoulder angle and everything else left as is,” I told him.

Already I was getting excited by the project because hisnter” VALIGN=”Top”> 200 2802 575 2.3 2.6 250 2558 479 0.9 4.1 300 2326 396 -1.8 6.2
(* 5 mph crosswind) Gardner, the longtime head man at Douglas, had championed the .20 caliber and considered it too good to be allowed to die. This ideal was passed along to his son, Tim, now president of Douglas, who passed the fever on to me some four years ago when he called with the news that Douglas was again making .20-caliber barrels. Not only that, but Walt and Eunice Berger, of benchrest bullet fame, were making pretty little .20-caliber bullets.

“What case would you use if you were designing a .20 wildcat?” Tim asked. A menu of possibilities flashed through my brain like numbers in a slot machine, then came to a stop on the .223 Remington. The powder capacity would yield at least 3800 fps with 36-grain bullets. There are plenty of actions already adapted to the .223 case, which would make building a rifle simple. And cheap .223 brass is available by the bushel. All in all, it was a wildcatter’s dream. “I’d go with the .223 case simply necked down to .20, with the shoulder angle and everything else left as is,” I told him.

Already I was getting excited by the project because his

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