After the qualification test, the training begins.

The officers fire "double taps," two shots in quick succession and change targets. Then they fire at different targets quickly, as instructors scream out which cut-outs are targets and which are innocent bystanders. At each stage, the instructors have the officers practice magazine changes.

"When you're engaged, with the adrenaline pumping, you can get so locked in that when you're magazine is empty it can really break your concentration," Green explains.

The day culminates in officer-to-officer combat. HUPD has each officer suit up in a facemask, neck protector and bullet-proof vest.

The range uses specially modified Glocks and "simunition" to simulate live-fire exercises. The Glocks fire small rubber bullets with paint-covered tips to mark where each round hits.

The officers practice suppression fire and face-to-face shootouts. The rounds leave large welts and blotches of orange paint where they hit but are not otherwise dangerous.

"It definitely adds a different perspective when your target is shooting back at you," Simas laughs grimly.

At the end of the long day, the exhausted officers reload their weapons with "street ammo."