. . before i found this forum, i watched a you tube video on breaking down a luger. the fella recommended giving the arms a thunk, and listening for a clear tone. it was supposed to indicate no cracks, i think.
. . so, even now, as my compulsory breakdowns have slowed to only about once an hour, mercifully, i give the arms a habitual thunk on my head and listen for the tone.
. . i think its about a d over middle c.
bill