So, this is something I have been wondering about since the Alpha. Why does the Security Forces use a cellphone when destroying weapon caches, while the Insurgents use an actual detonator? It's as if the Security Forces are using IED's, while the Insurgents are using proper explosives. I don't know if its just me, but I feel like it should be the other way around. Unless the devs accidentally did this or I'm an idiot, I don't know. Regardless, it's not game breaking.
It is because they scavenge the explosives from the enemy's weapon cache and DIY/rig the explosive. It is logical.
I asked about this a while too and it's not been changed.
I've since realized that idea may be that you're rigging the opponent's cache to explode using equipment found in that cache, which would explain the switch.
I guess that would make more sense then. I had thought it was being rigged by the "teams" explosives, not the "enemies" explosives, like how it is in most games. Actually, that makes it seem more interesting.
Friendly demo classes can blow up caches using their own explosives, rockets and grenades can work too, so rigging the cache is really more of an option of not having anything else on hand.
It's a great feature - a spent few too many times in that last game as the last one standing trying to blow a cache without anything to blow it up with, doing the run around to find something a bot dropped I could use.