Not as long as they're adequately crimped to prevent recoil from allowing them to move. Especially if they're being run out of an AirLite gun like my Wife's 342. I figure if it's good enough for these folks to do
Standard Pressure Short Barrel Low Flash Heavy .38 Special Pistol & Handgun Ammunition
(hit the view larger image)
it's good enough for my reloads, too!
I never thought to use it as a method to ID the rounds though?
Thanks!