Lawdog
The way i see it, the 45/70 will do anything a 450 Marlin will do with less pressures and cheaper, i have the 45/70 dies and 500 rounds of remington brass, also have a bullet mold.
I would have to buy the reloading dies for the 450 Marlin at $62.99, then the brass for the 450 is $46.88 per 100, brass for the 45/70 is $35.29 per 100.
When i buy a new rifle i like to buy at least 100 rds of ammo so i have the brass to reload, untill i can get set up to reload, i cant see buying 5 boxes of 450 ammo at $34.95 per box.
I was thinking that all we would have to do was remove the barrel and cut off 1/2 inch insert a 45/70 reamer and chamber, install and cut another extractor notch, no big deal for a friend of mine who is a retired machinest/ tool and die maker, all i would be out was a chamber reamer and a head space guage, he loves to tinker on guns so i was going to let him work on mine, the measurements i had and the measurements that were posted here were a lot different, as much as .10, no big deal, you know how it is when you get a brain storm that turns out to just be a brain fart, thanks everyone who came to my aid here with info and your 2 cents worth, its appreciated, now im going to see if i can find something in the medicene chest thats good for brain farts, WF.