“Are police-grade sniper rifles more deadly than assault weapons or High-powered rifles?”
450 rounds of .50 Cal - I should say yes
Since when does quantity = lethality? 450 rounds is nothing. A reloader may do that many in a single sitting. I personally reload about 10x more ammo then I shoot because I enjoy reloading as much, if not slightly more than shooting. As a result I guess I have a “stockpile.”
There is no law limiting the amount of ammo or firearms a person may own.