The other day I posted about boresnakes. Last weekend I went out to the range with a newly assembled upper. and I grab a new in package bore snake that I was going to run down the bores of the uppers I bought out so that I know they are clear of obstruction or debris before shooting.
That was an exercise in frustration.
This new boresnake was stamped with the caliber, very handy. Except that this stamping bent the end enough that it would not feed down the bore.