Here is the definitive answer regarding use of the .45 Colt in the Freedom Arms 454 cyl.. Post #20 from Bob Baker (owner of Freedom Arms) on Graybeard’s forum.
http://www.go2gbo.com/forums/index.php/topic,189645.msg1099239979.html#msg1099239979
Title: Re: using a 45LC in a 454
Post by: Bob Baker on January 13, 2011, 09:10:34 AM
The 45 Colt is .100 shorter than the 454 Casull. When shooting the 45C in 454 chambers, lead and powder residue is left in the chamber just ahead of the case. This build up of residue can restrict chambering the longer 454 cartridge and can cause excess pressure by not allowing the crimp of the 454 to easily open up to allow the bullet to exit the case.
Another potential problem is when the revolver is cooling down after firing it collects moisture. This moisture mixed with the lead and powder residue creates an acid which can etch the chamber underneath the lead and powder residue. With this condition, even if the residue is cleaned out of the chamber, the longer 454 case will now stick in the etched area of the chamber when fired and can be difficult to remove depending on the amount of etching. Over the years we have seen this problem more from guns in high humidity areas than from low humidity areas but it still occurs in the low humidity areas.
For some folks this seems to be an emotional issue and some folks even claim that all we are trying to do make extra money on extra cylinders. What we are actually trying to do is help our customers get the most trouble free life from their FA revolver as possible. I know of some customers that have shot thousands of 45C rounds in their 454 chambers with no problems but they thoroughly clean the gun when finished shooting. Other customers have ended up with one of the above problems fairly quick also. All we can do is put out the information, it is up to the individual what they do with the information."
FWIW,
Paul