When you abolutely positively have to kill it first time, or with the rest of the mag....
HK51K - 7.62x51 NATO (.308 Win) - my personal favourite,
7.62 only requires 108fps of energy to kill.
or it's little brother
HK53K - 5.56x45 NATO (.223 Rem)
Capitalises on HK's roller-locking mechanism, compact firearm, without losing the stability of a stock, & the hitting power simply not available to most pistola rounds.
This weapon is small enought to fit in the cockpit, & more importantly to tote when out of it, no point going to all the trouble of getting the permission to carry , if when you encounter the situation where you need it, you've left it in the cockpit because you were too lazy to take it out before going for a whizz in the scrub.
Penetration enough to cut a hole through a brick wall.
A slight modification of standard rounds , or purchase the more expensive nylon tip rounds, (these will open up the back of anything you hit) increase lethality, whilst losing some accuracy, but at the ranges we are porbalby talikng this is neglible.
The 51K was/is the weapon of choice by some of my previous colleagues who have gone on to better things, but more recent advances have seen some of them move on to new technologies, some however have remained loyal to the (tried & proven) above.
however whilst your gunlaws probably bite the big one almost as much as ours...this was my baby before little johnny & his team of hairy-lesbian-do-gooders took her away from me. (alas; now only criminals have guns)
Mossberg 590, 8 in the tube, 4 in the (compoiste) stock recess, heat shroud for when things get real busy, even a bayonet lug should things get very desperate (mil spec'd shotty, personally never did need it though).
