Yeah, old rimfire collecting is a chronic, incurable disease. It's kinda like love.
Yes, many old rimfires will accept Shorts, but I recommend they and CB caps not be used much, since they can erode the chamber, causing gases from long rifle shells to blow back past the shell if done to the extreme. Then, long rifle shells will be very difficult to extract because they expand to fit the eroded chamber.
I did it to a Rem 514 when a teenager; it wasn't pretty. I was buying shorts from Sears at 3 boxes for a dollar and I was a shootin' fool! I must have burned up three cases of the stuff through that rifle. It was my brother's, but he left it with me when he went to college. It sported a Mossberg scope with a rubber eyepiece in a side mount.
I wore it out and it was a mess when I traded it at Dakin's Sporting Goods in Waterville. They had a price on it that was higher than a new one and a Mossberg scope would cost. I think it was still in the store when it went out of business.
I don't feel too bad about trading it to them, since I bought almost a dozen guns, ammo, a set of golf clubs, fishing gear and other stuff from that store over several years. They treated me pretty good and my favorite salesman, Alex, taught me to reload and told me where to find woodchucks in the area.
Picher