In a way not surprising. Good way on Henry's part to minimize tooling costs. Keeping things common except for the bore. What seems odd though is lack of 'keying' studs to prevent interchangeability like this.
tractortad wrote:It gets a little more interesting. I just picked up another Henry Single in 357Mag and its barrel/forearm assmbly fits into the 45-70 and 44Mag receivers. In fact, all three are interchangeable with each other. It looks like the only difference in all three rifles is the diameter of their bores. The barrels all have the exact same length and outer dimensions...