With rifle ammunition? I get the feeling he's got pretty bad aim.
No surprise here. Our society's fixation on physical appearance is actually pretty damning.
Kill count depends a lot on whether the targets have room to escape or not.
Take VT incident of Seung Hui Cho, he had 32 kills being armed with a 22LR and 9mm pistol. Why? His targets had little to no room to escape, their only choice is to beef up defense on the classroom doors and fight back (one military guy tried to fight back Cho but got beaten and killed)
Then there is the las Vegas concert shooting. It was a long range D day style attack with lots of open space. In theory there are lots of room to escape, but there's no real cover and it was a open session for the shooter to unleash his rifles. He has scored about 500 injuries and 50 dead. Guaranteed, its the highest shooting score ever but no doubt, the high injury to kill ratio is caused by "spray and pray" shooting and not precise targeting as in close quarters combat like many school shooters did. Furthermore, the dumbass concert runners ran away and turned on the floodlights, illuminating the concert goers making them easy pickings.
The Christchurch shooter scored 40 something kills on the Muslims, why? Because
1.targets had no room to escape.
2.it was close quarters so the shooter can Target and not just spray
3.the shooter repeatedly fired at 'corpses' to ensure they are dead
4.slow police response (due to lack of experience of shooting on NZ)
So to sum up, what causes high kill count?
1.Targets locked in hard to escape place, or have to run miles to escape
2.Repeatledly shooting 'corpses' on the killers part, both Cho and NZ shooter did that
3.A good planning, to ensure 1 is possible
4.Of course, physical fitness is important. Both NZ shooter and Cho was tackled but fought back and succeed.
5.Also delayed police response is SUPER IMPORTANT. As soon you have three stars on GTA V you're busted or wanted.
I do not endorse mass shooting. My above conclusion applies to the multiplayer game Minecraft and it's gun model version 1.84.24132.