mad man,

There is (was ? as this was some years go) a very celebrated rimfire gunsmith in the USA (cannot remember his name), who slugged all barrels on guns he was working on.

Most had various 'tighter' / 'looser' sections as you went down the barrel.

He would cut at one of the 'tighter' spots, as cutting at a 'looser' spot would give less good accuracy.

He was of the opinion that a 'choke' was not needed on a barrel, providing that the crown was not on a 'loose' section.

Have fun & a good Sunday

Best regards

Russ