I've been firing .223/5.56 cases loaded with "civilian" primers in rifles with floating firing pins for 42+ years. Never had a "slam-fire", accidental discharge or anything else that could be attributed to a floating firing pin touching the base of the primer.
It is easy to dream up scenarios where the shooter routinely get his/her rifle in mud and doesn't clean it so that the firing pin is so impacted by a combination of fouling and dirt that it is held forward and can contact the primer and set off the cartridge. But in a well-maintained civilian rifle, this will never happen.
Personally, I think the advice mentioned in the OP's article is so rare and so speculative as to be just this side of myths like "Brasso is bad for brass" or other "urban legends".
It is easy to dream up scenarios where the shooter routinely get his/her rifle in mud and doesn't clean it so that the firing pin is so impacted by a combination of fouling and dirt that it is held forward and can contact the primer and set off the cartridge. But in a well-maintained civilian rifle, this will never happen.
Personally, I think the advice mentioned in the OP's article is so rare and so speculative as to be just this side of myths like "Brasso is bad for brass" or other "urban legends".
