The .22 Hornet is the first true varmint cartridge. In 1922, the Army decided to build a quality .22 rimfire rifle for training, target competition, and for sale to encourage marksmanship. The rifle was built at Springfield Armory, using the same tooling and fixtures as the M1903 Springfield -- and many M1922 parts will interchange with the M1903.
Craftsmen at Springfield were among the first civilians to buy this new rifle. As anyone who has shot one can tell us, the M1922 was not just a good competition rifle for its day, it was also a good hunting rifle. The boys at Springfield tried it on game including woodchucks. And there they encountered problems. First of all, a 'chuck is a pretty hefty critter, weighing several pounds -- much bigger than a squirrel or rabbit. Second, 'chucks are usually found in pastures, and your average 40-acre pasture is a quarter mile square, 440 yards on a side. So shots at 'chucks tended to be long range -- too long for the .22 Long Rifle.
The boys at Springfield cast around for a better cartridge, and the found one, the .22 Winchester Central Fire (WCF). The .22 WCF was developed in the mid-1880s as a black powder cartridge. Apparently the intent was to produce something with more oomph than the .currently available rimfires and to be reloadable.
The black powder heritage is apparent when you look at the case. Black powder combustion products are from 40% to 60% solid (depending on composition) and that's what creates all that fouling. A small bore, plus a large charge makes for real fouling problems. The case is therefore tapered, with a sloping shoulder -- that makes it easier to extract from a badly fouled chamber. That same shape also makes for less than stellar accuracy. Especially when coupled with 19th Century standards in manufacturing -- a standard .22 WCF case is a pretty sloppy fit in a standard .22 WCF chamber.
The .22 WCF didn't set the world on fire, but it did hang on until the 1920s, when the boys at Springfield developed a smokeless powder load that better than doubled the velocity of the .22 Long Rifle, and with a 45 grain bullet, rather than a 40 grain bullet, which was more or less standard in the .22 LR. They then re-chambered M1922s for the .22 WCF, and modified the bolt, firing pin and extractor. The story is that when Colonel Townsend Whelen first shot the smokeless powder version of the .22 WCF he remarked, "Boy, that's a hornet!" and the name stuck.
The Hornet was adopted by Winchester, and was soon surpassed by other .22 centerfires, but it has seen occasional times of modest popularity. The general pattern is a new generation of shooters are intrigued by the idea behind the Hornet -- a little case, a little bit of powder, and a fairly mild report with very low recoil. But then reality sets in, the Hornet just isn't that accurate.
I admit to falling prey to the lure of the Hornet -- my Hornet is a Kimber M82, and I've had it for many years. Here in the Ozarks, it makes a fine crow and coyote rifle. Sharp-eyed people may note that Arkansas game laws specify "nothing larger than .22 rimfire" for crows. But there is an exception -- during coyote season. Coyote season runs from the First of July through the 28th of February, then starts again about a week or so later with the opening of Spring turkey season, and runs through the 13th of June. In other words, it's pert' near always coyote season in Arkansas, and you can use the Hornet on crows to your heart's content.
My M82 is a beautiful little rifle, but it just wasn't all that accurate. To me, the Hornet is like a red-headed woman -- alluring, frustrating, attractive and capricious. Being a rather stubborn type, I set out to master the Hornet, and eventually developed a load that will regularly shoot sub-inch groups at 100 yards. Here is the secret to the Hornet.
1. Fire form your brass. The case is a sloppy fit in the chamber, but once fired in your rifle, it is a perfect fit -- in your chamber.
2. Disturb the brass as little as possible. The standard reloading die puts a lot of stress on a case, and Hornet brass is thin. We have to remember that when neck resizing, all the force is transmitted from the head to the neck through the walls of the case. I use a Lee Collet Die, where the only stress is radial.
3. Don't resize the whole neck. The Lee Collet Die is designed to size the whole neck and activates when the base of the collet tube contacts the shell holder. You can't adjust it by screwing it in or out. I put a couple of washers on the shell holder, around the case. The collet tube contacts the washers and activates early. You can look at my neck-sized cases and see a line around the neck, about half way between mouth and shoulder. The unsized portion of the neck acts as a pilot, centering the neck in the chamber.
4. Use the right powder. I use Hodgdon's Li'l Gun. Li'l Gun has a lower but more prolonged peak than other powders. It is therefore able to achieve high velocities at lower pressure. Typically, a case full of Li'l Gun will develop about 28,000 CUP, and the Hornet's max is 40,000 CUP. I don't weigh my charges, I use the case itself as a dipper. I fill the case and strike it off (draw a straight edge across the case mouth to brush off any excess powder) then tap the case lightly to settle the powder a fraction of an inch. This load breaks 3,000 fps over my Shooting Chrony.
5. Use the right bullet. No rifle will shoot more accurately than the bullets it is fed. I use the 35 grain Hornady V-Max. It shoots accurately, and is deadly on everything from crows to coyotes. But it has one even more important characteristic. Hornets usually shoot best when the bullet is loaded close to the origin of the rifling. This usually results in an overall cartridge length that won't feed through the magazine. V-Max bullets in .22 caliber all have about the same shank length -- the weight differences comes in the length of the nose. The 35 grain looks like it started out to be a round-nose bullet, and changed its mind at the last minute. You can load the 35 grain V-Max out to where the shoulder of the bullet actually touches the origin of the rifling, and still have an OAL that will feed through the magazine.
Follow these five steps, and you will produce .22 Hornet ammunition that will shoot as accurately as any other varmint cartridge, and will bring out the full potential of this fine little round.