Initial .22 centerfires were .226-.228 bores. Witness the .22WCF and Savage .22 High Power. Then in the late 20's when initial experimentation led to the introduction of the .22 Hornet, 1930-ish, the platform was the M1 Springfield .22 rimfire. That really started the ball rolling toward the use of "small" .22 bores. .224 barrels weren't readily available to experimenters/wildcatters but good .22 rimfire barrels were, so that's what got used. Winchester, Savage, and Springfield Armory .22 rimfire barrels got installed on many a single shot action in an effort to make use of the revolutionary new cartridge - the .22 Hornet. (Even though factory ammo became available in 1930-31, the first factory-made rifles didn't appear until two years or so later.) That early reliance on rimfire barrels is what set the tone for Hornet barrel dimensions and bullet diameters for years afterward. 

My personal theory about .223" bullets is that they were a compromise between the need to fit early rimfire barrel rifles and the .224 barrels that coincidentally were making their way into use. No big deal to shoot a .223" bullet in a .222" barrel, and no big deal to shoot the same bullet in a .224" barrel - it'll swage down or bump up as needs be.

I am not positve about this, but I believe Winchester was the first, or at least one of the first to offer the 22Hornet in 1933 in the model 54. They had .222 barrels (according to Rule) for quite some time, not sure when they started using .223 .224 Barrels in the Hornet. Savage had chambered the 22 hornet, with .223 barrels early on in their  model 23 and 219. I am sure .224 barrels were available to individuals some time before the large manufacturers switched to .224. Although when the Swift came out in 1937 they were fit with .224 barrels. Gnoahhh's theory is quite possible, but I would find it hard to imagine Winchester being too concerned with rifles with .222 barrels, although men like Whelen had considerable influence on companies like Winchester, especially given his role in the development of the Hornet. Besides, what's a few thousandths among friends. A lot to sort out, but my 54 Hornet slugged closer to .223. As Noahh pointed out, and is very often the case, Winchester introduced Hornet ammunition in 1930, but not the rifle till 1933. And as I have said, the hornet is one of my favorite cartridges, so sorting is sorta fun!!

gwahir, first off, need to correct my own spelling (mom was a teacher) stretching. Second, Have you tried .223 bullets, and did they shoot better or worse than the .224, in your experience?

gnoahhh,  Glad something did, it usually, read hopefully does. Do you happen to know how much earlier? The Savage that is. I like the 23, only one now is a 25-20, but had quite a few Hornets in the past. Always intrigued by the one piece barrel receiver.

rkba2nd wrote on Jan 14^th, 2021 at 6:05pm:


Savage M23D: 1932 (August, 1932 per Ken Waters)
Winchester M54 .22 Hornet: 1933 (according to David Bichrest, M54 historian) Hornet barrels exist with 1932 barrel dates but are on guns with 1933 serial numbers.

I have a late 54 .22 Hornet, 1935, with Targetspot Junior 8x, converted to K-Hornet by Lysle Killbourn himself . As much as I'm taken with single shots now, this one is such a sweetheart - kind of like an old girlfriend that keeps calling you after you're married. You keep her number tucked in a corner of your wallet, "just in case". Her sisters, the Lovell wildcats in Springfields, Krags, and a High Wall make it difficult to stay focused.

Life is good.