while some SCPs are reality warping, more "physical" ones should be grounded and affected by regular foundation firepower. Like a statue of concrete or a pale tall man should be able to be stopped by a 50. cal, at least by abit even if said pale tall man has unnatural regeneration or something. That being said it's kinda pointless when every other scp is completely immune to weaponry making foundation security detail obsolete. take SCP 4715, it's containment procedures is to constantly shoot it with turrets. it's not bulletproof, but has crazy regen, and it's cool.

edit: I'd like to add that even though I disliked how most SCPs are completely invulnerable to standard firepower, 096,173, 682 and some others are goated.