Winchester's Custom Shop offers a neat .450 in its short action. Neat. Pricey. Probably would hold its value, though, since it's an odd, but desireable duck.
http://www.winchester-guns.com/prodinfo/catalog/cstmguns/short_action.htm
The .400 Whelen is based on the 30-06 bumped up to where there isn't much shoulder to headspace on.
There would probably be enough shoulder to headspace .450 sized case necked to .40 w/o the belt, though the belt might help boltguns feed.
The Gibbs would be my choice, except it seems that they do not want you shooting full zoot 45-70 loads, which are equivalent to .450 Marlin. So, the enfield's strength at the high end (.450 level) might be in question. Someone may supply additional facts on that.
http://www.winchester-guns.com/prodinfo/catalog/cstmguns/short_action.htm
The .400 Whelen is based on the 30-06 bumped up to where there isn't much shoulder to headspace on.
There would probably be enough shoulder to headspace .450 sized case necked to .40 w/o the belt, though the belt might help boltguns feed.
The Gibbs would be my choice, except it seems that they do not want you shooting full zoot 45-70 loads, which are equivalent to .450 Marlin. So, the enfield's strength at the high end (.450 level) might be in question. Someone may supply additional facts on that.