I am working on a small cannon. The tube is the R-2 from SBR and I am attempting to make a field carriage for it. It will be 'in-the-style' of the split trail revelutionary war carriage, but not faithfully detailed. Do you guys have any suggestions for suppliers of trunnion caps? The trunnions should end up about 3/4" in diameter (if I can stop filing on them). I have no experience working metal and will need to buy them from someone. Question two is about the ball size. The bore size is .75 and I can buy balls that are either .710 or .735 - does it really make a difference? I have seen the windage formula on the board before but can't locate the posts and don't know if the .735 is really safe. Anyway, thanks for any help you can give a new guy.