Homer - I suggested something like that, in the .458 2", but in retrospect, that would require the barrel to be set back almost 4/10's inch for the 2", 3/10's for the .450's 2.1" case. The Marlin chamber has litterally no leade/freebore, and therefore the oal will be 2.55" to 2.6". My chamber allows me to crimp in the rear cannelures on bullets that have them- 350gr. RN hornady, 400gr. RP, etc - seated out as far as they can be. This litterally increases the case capacity to about that of a standard .45/90's 2.4" case. That is why my little 2" made over 2,050fps with 510gr. WW solids in the Mauser rifle's 22" bl. It's no slouch.