[Andrew Rowe]

Here are the two for reference, the sleeve dia. appears to be the same, at about 31mm ( have not got my verniers at hand ) and the tube length is about 87mm on the 6pdr and 53mm on the 2pdr. from the face to ( that is the side that goes against the block ) is about 119mm overall length to end of firing pin and the 2pdr is about 98mm. The threads have about the same dia. at 40mm overall, so there you go, with a bit of rework you could quite easily fit a 6pdr into a 2pdr, as even the locating pins and safety mech are same dia. and in the same locations offset from the centre line the same, Cheers Andrew.