The .44-40 up until the cowboy shooting craze was a basically dead
cartridge. .44 Magnum replaced it for rifle and pistol shooting and
it wasn't chambered in much of anything since before WWII. It's one
of the calibers that they do one run of during the off season,
hopefully a large enough run to last the rest of the year and that's
it. The original guns that it was chambered in have either worn out
or joined collections, original Winchesters and Colts in good enough
shape are mostly too valuble to shoot. The cowboy shooters have
revived that and several of the 'dash' calibers, but it's a specialty
caliber, don't expect to see it on any big boxes' shelves. Plenty of
outfits you can order it from, expect to pay upwards of a buck a
shot. Anything lower is a pretty good deal. What with current demand
for the "military" calibers, there's no off season and the obsolete
numbers will be waiting in the queue for production for quite awhile.
Get it while you can. Save your brass, new brass is pushing 40-50
cents a case.
If you want to pay less and shoot more, brass is available, dies are
available, bullets and molds are available. You can get into
reloading for it for the current price of two or three boxes of ammo.
Reloading for it is probably a lot less hazardous than going to a
mall, you aren't going to pick up any contagious diseases. Smokeless
powder is a flammable material, but so are a lot of household
materials and a lot more so. Primers require some respect in
handling, you have to be very careless, though, to get hurt handling
them. .44-40 bullets aren't the current standard .429-430" diameters,
they cost a little more if jacketed or can easily be made(by you) to
whatever size your barrel needs.