Tim,
Thanks for sharing that wealth of information. I called H&R about
the 280 REM barrel, and they are out of stock.
Tonight I held a 7x57 Ruger #1 and I may just buy it instead. That
is my Dream Rifle.
Why don't you put up a WTB ad for a .280 barrel. I know that there was one for sale in the classifieds (don't remember when), try browsing thru the older ads, you might find one, there is also the ebay option, but that is a little more pricey.
I would also suggest one of the older calibers like the 30-30 or 45-70, both of these calibers seem to be super accurate out of Handi's. If your heart is set on something in the .28cal range, how about the 7-08mm? H&R has them in stock, ammo is easy to come by, so is brass (can be easily made from .308/7.62x51 brass).
FWIW, I own a 7x57 Ruger #1, (I also own or have owned most of the different model Ruger rifles, and some of their pistols over the years) and I love the way it handles, but truth be told, it's not the most accurate rifle I own, as a matter of fact, and I know most Ruger lovers are going to jump on me for saying this, but Rugers are: rugged excellent utilitarian rifles, good for what they were designed for; hunting, with pie plate accuracy, but not really super accurate rifles. If your looking for minute of angle accuracy, get a Savage, Remington, or even a push feed Winchester bolt gun, not a Ruger.