Back in the 1920's my dad said grandpaw had old 45-70 they would go to stoore and buy 410 bore shells in 2 1/2" and would shoot them in the old gun could this be true or just another old story told to me 70 years ago. thanks BE

They probably did just that, mainly because they probably only had the one gun and needed some diversity in loads such as shotshells. Probably not the best thing for the gun, but in limited use or survival the 45-70 action is way strong enough for a 410 shotshell.