From what little I have gathered from open sources thus far…the .284 cartridge was born in 1963. The Winchester model 100 was born in 1961. So The first year of production has to be 1963 for a Model 100 chambered in .284. The production line lasted until 1973 with about 260,000 produced. Most are chambered in .308…the others in .243. 12 year run averages 22,000 per year total. Take 22,000 times 2 = 44,000 not in .284 in 1961 & 1962… leaves 216,000 total. Say 20% of those were chambered in .284. that leaves a total run of 43,200 for the .284 from 1963–1973. The 19″ carbine is the rarest… so say 10% of those are carbine .284’s leaves 4,320 carbines with a 19″ smooth stock without checkering, 38,880 in 22″ barrels. For the ten year run of the .284 chambering, that’s gonna be 432 per year for the carbines, 3,888 for the 22″ in .284…

So from my simple math skills learned from a crappy high school in the 1970’s…and lacking access to Winchester’s data base and records and me refusing to pay $250 for a shipping record… That means my 1963, 22′ .284 is a first year 1 of 3,888….i.e. rare for any Winchester or any gun whatsoever that has a brand name collectable firearm.

Jus sayin’…