Henry I.
My barrel break-in is simple and you find it in FAQ. Button rifle barrels like the Handi barrels are very smooth and need very little in the way of lapping.
Not cleaning a barrel is a crock of rubbish . Bench rest shooters that shoot bare bullets clean their barrel after every match, that is five shot plus a few sighters. Even with Moly plated bullets I clean every 25 Rounds in a match.
These barrels are very expensive (more than two Handi's) and if any body thought that they would ruin their barrel by cleaning they would not do it for sure.
Only clean barrels shoot accuratly. But if any body is only interestest in machine gun accuracy by all means forget about cleaning.
There are hundreds of cleaning cleaning supplies manufacturers, stressing the benefit of clean barrels and how well their products are working and without damaging barrels.
Ignorant thoughtless cleaning regiments is what's ruining barrels.