bronze antique key wanted

[sagitario]

bronze or steel 1 swg x 5 1/2 inch long key wanted for old church lock, must be a blank as it has to be cut to suit.

[Tom Gordon]

There is more variety to blanks than you realise. You also need to know if the bit (flat square part) is long enough and tall enough and the correct distance from the collar. The important length to measure is from the collar to the bow (handle). You are not going to get that in bronze and are likely to need a wedge shaped bit to allow the cast iron enough strength after you have cut a lot away. Have you thought about whether the cuts need to be made on the outside of the blank or from a central slot. You are going to have a hard time without a specialist keysaw if it is a "bridge warded" lock and have to make the cuts from the inside. Very often it is easier and better to get a locksmith to do it
Cheers
Tom