Somewhere in Afghanistan
Sometime in the ‘90s

“That’s him.” the squad spotter said. “And, ah shit, he’s already inside. I think we’re going to need the special ammo for this one…”
“Golf 1 actual requesting permission to go Charlie-Bravo, over.” the squad leader sent over his radio. The squad of 8 operators were concealed in a dip behind the rocks after a day’s march from a helicopter insertion on the other side of the mountain. They were staring down another unassuming cave entrance through their weapon optics, having just confirmed the HVT’s presence. 

“Golf 1, this is Romeo Command, you are clear to go Charlie-bravo, authorization code Foxtrot-niner-alpha-bravo-delta-zero-echo. Do you copy?”
“Copy authorization foxtrot-niner-alpha-bravo-delta-zero-echo.” The squad leader punched the hexadecimal sequence into a safe on his weapons specialist’s rucksack.The entire safe was extremely cool to the touch- about 5 degrees Farenheit, making the squad leader regret taking off his gloves for this.  As he hit enter, the safe popped open, revealing a single magazine of 7.62x51mm NATO ammunition along with a dense fog as the cool air inside mixed with the warmer air outside. 

The weapons specialist removed  his current magazine and cleared his M110 SASS, a black-tipped cartridge plopping onto the dirt beside him. He carefully inspected the small 10-round  magazine of “special” ammo, making sure the temperature gauge set on its left side was firmly in the green, and then tapped the magazine’s rear firmly on his helmet to make sure the bright blue-tipped ammunition was set to the rear of the magazine to prevent any misfeeds. He slid in the small 10-round magazine and chambered a round, then took up a firing position.

“Distance to cave opening is 1 click.” his spotter said, a grenadier who’d been given a laser target designator. Meanwhile, knowing what was coming, the rest of the squad sealed up their uniforms and gloves, and finally put on their gas masks. 
“Thanks Bill. Everybody got their MOPP on?” A muffled chorus of affirmation came from the rest of the team. 
“Specialist, fire at will.”

The weapons specialist  sighted in on the cave opening through his scope and elevated his weapon so the black maw of the cavern just barely touched the bottom of the scope, compensating for the unusually heavy bullet’s rainbow trajectory. Finally, he flipped down his front scope cover, dimming his vision significantly, placed his left hand over his left eye, and fired.  The loud report echoed through the Afghani mountains before a globe of impossibly bright light exploded across the cave entrance, and vanished just as quickly. A miniature mushroom cloud began to form, concealing the damage done to the cave system, as the tremendous KABOOM reached the troops, louder than any artillery barrage, and dwarfed the reverb of the initial firing meandering across the mountains.

“Hell, they’ll probably hear that in Kabul.” one of the operators joked. After the smoke cleared, the weapons specialist confirmed the effect of the round- the cave entrance had been replaced with a large crater, and the rest of the cave behind it was collapsed in on itself. The specialist dropped his mag, cleared the chamber, reloaded the ejected round into the special magazine, and put it back in to the safe on his rucksack before locking it back up.