Something that will get you through anything and always be there to fire. Something you can always count on, no matter what. Cold, heat, wet, dirt, mud, drops, falls, bites, claws.
Is there anything in your mind, that you trust to take all that and keep on tickin’?
The fewer moving parts, and fewer automatically cycling parts, the more reliable.
I’d reckon that mechanically a fixed pin, single loaded slamfire shotgun is going to be nearly 100% reliable. The only malfunctions being user error or bad ammunition.
Of things in the realm of reason, a bolt action rifle chambered in a rimless cartridge will be very reliable.
That said most big name, widespread firearms are can be very reliable. Each design has certain specifical makes/models that will be better, and points more likely to fail and certain types of jams, but on mature designs they can usually be easily cleared.
Would you be willing to take a slamfire shotgun over something magazine fed? Is the reliablity difference that big of a factor to sacrifice so much else? Most people say usually not.
I’ve heard of a HK USP lasting 200k rounds without parts change
It really depends on what your use case is. Are you an author looking for a gun for your post apocalyptic character or are you someone looking for a carry handgun?
I don’t think I’ve ever heard of a Ruger No. 1 malfunctioning.
If you had to survive with one gun for the rest of your life, would you chose this?
Survive what? Survive where?
Survive when?
The year is 1997, you’re living in an alternate timeline where mars has been colonized for decades. You’re in Habitat 77, isolated from the rest of the habitats. G-raptors, genetically modified dinosaurs breed to survive on mars prowl the halls. What modern firearm do you choose?
Then no, not that single shot Ruger. I want a belt fed M60 machine gun with an ammo belt attachment.
Potentially anything, potentially anywhere.
I reject the premise of the question. Different situations call for drastically different equipment:
- A summer in the woods in Alaska poaching small game for food: bolt-action .22, maybe a CZ 457.
- A winter in the woods in Alaska poaching small game for food: forget it. You’re going to die if you’re asking questions like this.
- A desert island: flare gun.
- Urban area, breakdown in social order in which you have gunfights with your neighbors over a rapidly dwindling supply of resources: Lincoln’s Repeater.
Rifles:
AK47, Garand M1, Lee Enfield No4 Mk1, SKS
Pistols:
Glock 19, CZ 75B
Shotgun:
Mossberg 500
Pump action Remington 870