A long time ago, I machined an aluminum block that greatly facilitated the loading of a friend's ML shotgun with choke - a modern gun the brand of which I don't remember. The block was bored, based on this gun's measurements/dimensions, such that the block slipped over the barrels aand aligned bored chambers with the muzzles. The bored chambers were cyl tapering to the choke at muzzle. Thus, the wads were easily pushed into the muzzle and were correctly aligned with the bore. This gun shot well and kicked my butt two of three years in a ML Skeet competition. Not hard to do, but requires custom machining.
