It may be do-able, depends on the gun. We have commissioned many 12 to 16's and several 20 to 28's but no 16 to 20's. The trick is finding someone happy to take on the issues of barrel alignment with the 16's breech centers but the 20's smaller muzzle diameters. Also the difference in OD of the barrel tubes at the point of joining. You will probably also have issues with forend wood fit with the smaller tubes and the loop may need altering to latch properly.
Keeping the same barrel length is not restricted by rib length as these can be extended be welding on a new section.
Price in the UK would probably be about 25% to 50% more expensive than same gauge sleeving.
You might need to have special tubes made if your 16 is unusually heavy in the joining area and this will further add to the cost.
Last edited by Toby Barclay; 03/12/17 04:50 AM.
