IMO some of the best 'combat' hand guns are still based upon the .45 caliber 1911. Springfield and Sig have some nice .45 calibers along with Kimber. H&K have some excellent .40 caliber models. Street cannons such as the desert eagle .50 cal. are certainly impressive weapons. Considering that we are talking combat weapon which will be utilized in Close Quarters Battle (CQB) the bigger calibers are somewhat unwieldy. The weight of the .50 Cal, the magazine and ammo itself are to be considered in a combat load. Also if you are covering an area for an extended time you will fatigue much faster.
Firing the bigger caliber handguns with one hand can be a disadvantage for quick accurate follow up shots. You can and will find yourself shooting one handed because you are doing things such as holding flashlights, grasping things, pushing/pulling things before and sometimes during an engagement.
The .45 and .40 caliber handguns dont have devastating terminal ballistics of the .50 caliber but they are more nimble, faster to bring on target (and stay there), and lighter. Usually the outcome is the same whether you shoot someone in the chest area or head with either caliber. It all comes down to what works best for the individual depending upon their mission/threat and skill level. Have a great day.
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