K-Hornet is Old and Improved
    by Rocky Raab

    (Originally published in the January, 1993 issue of The Varmint Hunter Magazine. Edited and updated , June 2000.)

    The prairie dog sat motionless in the early morning sun, alert for danger but seemingly unconcerned by the strange shape that loomed over a rock 150 yards away. Peering through my scoped Contender from atop that rock, my finger started to squeeze. The pistol barked, and in the scope I saw the range-devouring little rodent abruptly disappear in a cloud of dust.

    Here to keep these pests thinned for a rancher friend, I reached for another diminutive .22 K-Hornet round as two more 'dogs popped up. As the sun arced upwards, more than 200 doses of 45-grain jacketed medicine followed that first one down the T/C Contender's 10-inch barrel. The cartridge that ushered in the modern concept of varminting nearly a century ago is still thumping them as well as ever. In fact, it's even better.

    Rocky's Contender 22 K-Hornet
    A bull-barrelled Contender in 22 K-Hornet is an accurate and fun varminter out to about 175 yards, where this ground squirrel was taken by the author.

    The credit for developing the .22 Hornet may be awarded to numerous individuals, starting at least as far back as 1888. Way back then, the legendary A.O. Niedner was attempting to soup up the anemic .22 Winchester Center Fire. Limited to black powder, Niedner was unable to push the round's 46-grain lead bullet much past 1,500 fps. At about the same time, however, a Massachusetts gunsmith and experimenter named Reuben Harwood was also tinkering with small rifle cases, but using Dupont No.1 Smokeless Powder, which had just been released. Using a 60-grain bullet and cases necked down from either the .25-20 Maynard or the .25-20 Winchester Single Shot (some historians disagree on which) Harwood was able to reach a claimed 2,000 fps. He called his development the Harwood Hornet. If there had been suitable rifles built to handle the hot little cartridge, and if Harwood had not stopped promoting his round due to a serious illness, the sport of varminting and the .22 Hornet might have been born ten years shy of the 20th century.

    Instead, the concept languished for 35 years. In that time, companies like Savage and individuals like Niedner, Charles Newton and others developed rounds like the .22 Newton and .22 Savage High Power. Then in 1930, Army Captain Grosvener L. Wotkyns published an article that resurrected the modified .22 Winchester Center Fire. The "new" cartridge was immediately and loudly championed by Colonel Townsend Whelen, who called it the .22 Hornet.

    Whelen, Al Woodworth of the Springfield Armory and ballistician Captain George Woody soon had the insight to meld the modified .22 WCF case, DuPont 1204 smokeless powder and jacketed bullets they literally pulled from a pipsqueak revolver round called the 5.5mm Velo Dog. (The curious name stems from the fact that the gun was actually intended to protect cyclists on their velocipedes from angry dogs!) The combination of case, powder and jacketed bullet was a winner and the shooting world hasn't looked back since. But even a terrific round like the .22 Hornet can be improved, and that is exactly what happened not long afterward.

    For the uninitiated, "improving" a rifle round generally means increasing the powder capacity of a case by reducing the taper of the case walls, steepening the angle of the shoulder, moving the shoulder forward, or combinations of all three. The added case capacity allows a handloader to use a few grains more powder and thus gain more velocity, sometimes a goodly amount more. Such improved rounds are not, technically speaking, wildcat cartridges, because they can be formed by firing normal factory rounds in the gun's modified chambers. True wildcats use cases that must be formed or altered outside the gun, and no factory round can be fired in a wildcat chamber. Gun guru P.O. Ackley was the undisputed king of improved cartridges, but the "improved" .22 K-Hornet is the creation of yet another firearms experimenter, Lysle Kilbourne. The K in the improved Hornet's name is a tribute to Kilbourne.

    As good as the Hornet was, and still is, the blown-out Kilbourne version is significantly better for several reasons. First and most obvious is velocity. In rifles, the regular Hornet gets around 2,700 fps with 46-grain factory ammo. The K-Hornet often adds 200 fps to that, and some rifles can get as much as 3,000 fps. That's right: Kilbourne's Hornet churns up exactly double the velocity of Niedner's original creation.

    Another benefit of Kilbourne's improvement is a much-reduced tendency to stretch cases. The original Hornet headspaces on the rim, as do all rimmed rounds. But it couldn't have been otherwise, for it is impossible to headspace on the Hornet's extremely shallow five degree shoulder. Also, because the long, sloping case usually fails to fill the chamber completely, the Hornet case stretches forward appreciably every time it's fired. It's all too easy to set the shoulder back too far when resizing. Continued firing and excess sizing leads to yet more brass flow, case stretching and eventual case separation. Even a careful reloader finds he must trim Hornet cases often because brass flows all too readily up into the neck.

    The blown-out K-Hornet, on the other hand, can and should be sized to headspace on its sharp, 35-degree shoulder. So sized, its minimum taper body and sharply angled shoulder reduce case stretching and contribute to case life, as Ackley claimed for most improved cartridges. And in fact, properly sized K cases grow hardly at all. Case life is long with its tiny charges of powder and relatively mild pressures. I had one batch of K-Hornet cases that had contentedly gone through seven firings with no discernable case growth, and would have undoubtedly gone on longer. But at that point I washed the dirty cases in a detergent solution that, unknown to me, contained ammonia. The ammonia embrittled the cases so much that nearly half showed splits on the next firing and I discarded them all. Chamber-matched sizing also contributes to greater accuracy, because the case is more nearly concentric to the bore. Bench rest shooters have conclusively proven this.

    Much more difficult to demonstrate are some other claims by improvement aficionados. Sharply angled shoulders, some claim, allow for more efficient burning of the powder with less barrel erosion. This is based on the theory that powder kernels in a tapered, sloping case are blown out of the brass at high velocity. The effect on the first inch of rifling is much like sandblasting. In contrast, say the theorists, cases with sharply angled shoulders either retain most of the kernels within the case, slow them significantly, or deflect the kernels enough that they strike the inside of the case neck instead of that critical first inch of rifling.

          More Than a Rifle Round
    Although the Hornet and K-Hornet are best known as rifle rounds, their tiny diet of fast-burning powder also makes them truly spectacular pistol rounds. In fact, the .22 Hornet was the first cartridge chambered in the revolutionary Thompson Center Contender. Warren Thompson said it was his Contender's most accurate round; in many Contenders since, that continues to be the case. With its favorite load, and on my best days, my 10-inch K-Hornet barrel regularly shoots 1.2" groups at 100 yards. That may not be as good as the great Bob Milek could get from a Remington XP-100 in .223, but it's not too shabby for the likes of me, and it could possibly be improved a bit with a scope of more than 4X.

    A 10-inch K-Hornet barrel doesn't give away much in the way of velocity, either. With top loads of WW296 powders, I get 2600 fps over my Oehler Model 35P chronograph. Speaking of powders, until recently there simply weren't many that were suitable for either version of the Hornet. But today, the situation is much improved. In addition to WW296, H110, Accurate Arms 1680, IMR or Hodgdon 4227, AA-9 and WW680 all work well. Both IMR and H4198 seem to be just a tad too slow, especially in pistol barrels, giving about 150-200 fps less velocity even with compressed loads. By the way, I find that many of the reported loads from the 1950s using Alliant 2400 are dangerously hot with modern components. For that reason, I no longer recommend 2400 in any Hornet or K-Hornet load. More than taking up the slack, however is Hodgdon's Lil' Gun powder. By far the best powder ever for either version of the Hornet, it gives higher velocity at lower pressures than any other offering. At its best with bullets of 40 or 45 grains, it's my new standard.

    Ideal Hornet Powders
    Ideal powders for the K-Hornet include Hodgdon Lil' Gun, AA 1680 and Hodgdon or IMR 4227.

    A few powders that I haven't tried yet also have promise, such as Norma R-123 or N-200, or Vihta Vouri N110. Loads using these powders are listed in several manuals, but since I started using Lil Gun, I see no reason to experiment further. For the record, this is place for me to make the usual disclaimer: neither I nor this magazine accept any responsibility for the use of published reloading data in your firearms.

    To fireform cases to my K-Hornet chamber, I used to load cheap military 55-grain FMJ bullets over 3.5 grains of Bullseye and simply fire them in my Contender. This load gives velocities about like a .22 WMR, and I suspect it might make a good turkey load if it stabilizes in your gun. But it sure seemed like a waste of components and effort.

    So now I simply load virgin Hornet brass with a factory-equivalent Hornet load consisting of either 9.0 grains of AA9, 12.0 grains of W296 or 13.0 grains of either AA1680 or Lil' Gun under a 45 grain bullet. Because of the K-Hornet's enlarged chamber, these loads give a slightly reduced velocity. But out to about 100 yards they strike at nearly the same point of impact as my full-bore K-Hornet loads. On varmints, the impact results are practically indistinguishable. For ranges out to 150 yards, full K-Hornet loads at 2500 fps or more are better.

    This may not seem like sagebrush-burning velocity when compared to a .22-250 or even a .223, but the extremely fragile bullets designed for the Hornet are almost explosive in their effects. A varmint hit with one is well and truly "Contenderized." Suitable bullets are generally found from 35 to 45 grain weights and .223 or .224 diameters. Bullets heavier than 45 grains are a poor choice, however. Those are designed for use at .223 Rem. through .220 Swift velocities and won't expand from the K-Hornet.

    Very early Hornet rifles came with .223-inch bores, but any made in the last 50 years are bored to .224. Most guns will shoot both size bullets about the same. The 45 grain types have a slightly better ballistic coefficient and sectional density, which would seem to make them a better choice than 40 grainers, but in practical use there isn't much difference at ranges under 200 yards. Nor is there a clear-cut choice between hollow-point and soft-point bullet designs. But don't forget to try the new Hornady 35- and 40-grain Vmax and the Nosler 40-grain Ballistic Tip. With any of these bullet options, just use whatever your gun shoots best. It's fun to experiment, so go ahead.

          The Word is...Fun
    Fun, in fact, may be the most appropriate word to apply to the K-Hornet. Recoil is so light that with a firm hold, you can see the bullet strike even through a scoped Contender. Muzzle blast can be sharp, necessitating good ear protection, but it's less than the crack of a .223. Farmers and neighbors may make distinct objections about the bang of a .22-250 in their back 40, but they hardly ever object to a mild-mannered Hornet. Quite the opposite, the Hornet seems to draw attention.

    I can't count the number of times shooters have come up to me on the range or afield and asked what the heck was shooting. When I show them the rakish, scoped Contender and its sexy little K-Hornet rounds, they almost always beg to try it. I have yet to see anything but an ear-to-ear grin after their first shot. Most beg for another and y t another shot. Many have gone away saying they absolutely MUST have one just like it.

    And that's not terribly difficult to do. Although K-Hornet rifles are somewhat rare on the used market, regu ar Hornet rifles are fairly easy to find, and any competent gunsmith can obtain a K-Hornet reamer for rechambering. ornet barrels in 10-inch bull configuration are still listed as a regular item for the Contender, and a variety of Ho net and K-Hornet barrels can be had from Fox Ridge Outfitters, T/C's official custom shop. I found my early-producti n octagon K barrel for a give-away price at a gun show. With the Contender, you can even bridge both worlds by obtai ing a carbine-length barrel and carbine shoulder/forearm stocks. As an unabashed T/C fan, I might also mention that he T/C line of scopes and mounts make ideal complements to either the pistol or carbine setup.

    With either rifle or pistol, I think that the K-Hornet version is the way to go. With the K, you gain a significant velocity increase with only a negligible increase in powder charge. You also gain much increased case life and more inherent accuracy. You give up nothing in the way of flexibility, as factory Hornet ammunition works perfectly in any K-Hornet firearm. To shoot the K-Hornet version, of course, you must handload. Here's where you discover its real flexibility. The K can be handloaded to duplicate the performance of everything from the .22 WMR to nearly the .222 Rem. That makes it fit for everything from tin can plinking and squirrels up to coyotes.

    Yet, compared to the combined costs of a small game/plinking gun plus a dedicated varminting rig, a K-Hornet can not only be bought but fed for a mere fraction of the expense. Reloading costs are extremely low. Dies are readily available from Lee, Hornady, RCBS and others, and components are among the cheapest available. Bought in bulk from outfits such as Midway, brass costs as little as $10 per hundred and bullets can be had for about $7 per 100. Regular strength small rifle primers are all that's needed in this tiny case, even for ball powders; another slight cost savings. A single pound of powder can produce as many as 600 full-power loads. All together, the Hornet is probably the least expensive center-fire rifle round on the market. By way of comparison, reloaded .30-06 ammo will cost at least 30 cents a trigger squeeze. Ten bucks gets you about 33 shots. For the K-Hornet reloader, $10 produces 100 rounds of K-Hornet ammo. That's only a dime a pop. At that price, almost anyone can afford to shoot the K-Hornet a lot. Furthermore, the K's negligible recoil and milder muzzle blast make it a lot more than three times the fun of plinking with an ought-six.

    K-Hornet Bullets
    The K-Hornet can handle bullets ranging from 35 to 50 grains, although best performance is with 40 and 45 grain.

    But for all its economy, the K-Hornet is by no means a cheap compromise. On fox, coyote and other game where undamaged fur is the valuable goal, the K-Hornet usually provides complete within-the-animal bullet fragmentation with its lightest, most fragile bullets at maximum velocities. For those who prefer to take fur-bearers or turkey with through-the-animal penetration and no expansion, no better round could be imagined than the K-Hornet loaded to about 2,000 fps with a 55-grain full-jacketed bullet. As far as range is concerned, the K-Hornet is at its best from plinking distance out to about 175 yards. And let's face it, many of those 400-yard prairie dog shots we read about were made with a high-powered keyboard. Oh, I'll give some shooters the benefit of doubt and admit that such shots can be made. But I'd wager that the vast majority of all kinds of shots are made at 200 yards and under. And within those limits, the K-Hornet is about as perfect a round as could be designed.

    For a cartridge whose genealogy stretches back more than a century, the K-Hornet is a spry and useful little fellow indeed. For the fun shooter, average varminter, small game hunter, turkey hunter or fur collector, there's no doubt that Harwood, Wotkyns, Whelen and Kilbourne were right. For small game, varmints and just plain fun, the improved Hornet is "Oh, K!"

    All loads, especially those listed as Max, should be approached very carefully using standard reloading procedures.

    Author's Pet Loads .22 K-Hornet, T/C Contender 10"

    VELOCITY (fps)

    WW296 11.5 Sierra 45 Soft Point 2650 2.1" groups. Max load.
    AA1680 13.3 Sierra 45 Soft Point 2525 1.2" Moderate load
    H4227 11.4 Hornady 45 Soft Point 2500 2" groups. Mild.
    Lil' Gun 14.0 Hornady 40 VMax 2875 1.25" Best load*
    AA-9 9.0 Hornady 45 Soft Point 2375 Fire forming, short range load
    Bullseye 3.5 Any 40-55 1600 Plink, small game

    Note: All loads used Winchester brass, Winchester small rifle primers and ..224" bullets. All were fired over an Oehler Model 35P chronograph placed 10 feet from the muzzle. Five-shot groups at 100 yards, 4x scope. Velocity rounded to nearest 25 fps. *This load not tested in original barrel in 1993.

    Manufacturers referenced in article:

    Thompson Center Arms
    PO Box 5002
    Rochester, NH 03867
    (Catalog; Contender pistol, carbine; scopes, etc.)

    Fox Ridge Outfitters
    400 N. Main St.
    PO Box 1700
    Rochester, NH 03867
    (Catalog; T/C custom items)

    Hodgdon Powder Co. Inc.
    Shawnee Mission, KS 66202
    (Powder, load data)

    Scot Powder Company of Ohio, Inc.
    430 Powder Plant Road
    McArthur, OH 45651
    (Powder, load data)

    Accurate Arms Company, Inc.
    McEwen, TN 37101
    (Powder, load data)

    5875-D W. Van Horn Tavern Rd.
    Columbia, MO 65203
    (Monthly catalog, reloading supplies, tools)