For starters, I have not built this kit. Dixie rates it as a level 2 kit which is saying it is an intermediate skill level. To quote their catalog:
Stock:95% inletted. Will require some minor stock shaping and final fitting of metal to stock, final sanding and finish. Will require holes to be drilled.
Metal will require polishing and browning or bluing.
That being said, the biggest driver here is the fit of the breech with the stock. This must not have gaps in it. The rear of the barrel tang can have a small gap with the wood, and in fact a gap of 1/64 - 1/32 is preferred so that the shoulders of the breech transfer all of the recoil and the tang transfers none.
If the barrel won't fit because the barrel rib is hitting the wood, and this wood will be covered by the nosecap, then by all means, remove a little wood. As long as the nose cap will cover the area, you don't have to be too precise here.
When the barrel fits fully down into the barrel channel, I would then suggest temporarily installing the nose cap so that it seats out on the stock. Then, with the breech seated against the stock, lower the barrel into position.
When the barrel rib starts to hit something (as you say it does) then as you indicate, something has to go.
Because filing the front of the nose cap is a lot of work, my first feeling is the rib must be shortened but study the situation before commiting anything into chips. If that would solve the problem then measure how much interference it has, mark the offending end with a black permanent marker and remove the rib from the barrel. File off the correct amount.
While you have the rib removed, try placing the barrel in the stock to make sure it is going to fit. If the sides of the barrel fit tight, use a sanding block and widen the channel so the barrel fits in easily. You might also have to file the inside surfaces of the nose cap to clear the barrel.
If the barrel fits, now try reinstalling the rib with the barrel still in the stock/nose cap. You may find that a little more material must be removed from the rib. This joint doesn't have to be "tight". In fact, a little clearance here will make removing the barrel on the finished gun a little easier.
I am sure you can see where I am going with this so I won't go on, but this kind of hand fitting can be expected in several areas. The primary thing is to study the situation before making any chips.
Hope this helped.
PS: I am going to ask to have this post moved to the Builders Bench. Hope this is OK with you.
