I can't agree. My 450#2 conversion is on a 12G action and weighs 11 1/4lb.

I would be very cautious of using a circa 1895 gun for a 470NE conversion, for metalurgical reasons.

It would perhaps make a nice 577BPE conversion 577 21/2 etc.

Respectfully by the time you have done this and restocked it to a good standard from scratch, you can buy a double. (A 470NE Manton boxlock sold at Holts in june for $ 6000.00.) You will not get away lighter than this for a good conversion and when it is done it still will be worth next to nothing except to you.

Regards