Virtually all experts agree that for self-defense, the 1911 should be carried cocked and locked — that is, hammer back and thumb safety engaged with a round in the chamber and a full magazine. (If the hammer is not cocked, the safety on these single-action pistols will not engage; it is “locked off,” so to speak.)
Firing pin is shorter than the firing pin channel and it has a firing pin spring, it is nearly impossible to hit the hammer with enough force while it is down to make the firing pin detonate a primer. Id say completely impossible but theres that 1 in a million chance.
Inside-the-Waistband (IWB)
For me this is the most comfortable and concealable way to carry a 1911. With 3/4s of the pistol tucked inside your pants, all you need is an un-tucked shirt for complete concealment.
Hammer down on a live cartridge introduces a substantial degree of risk while giving very little in return. With cocked and locked, or empty chamber carry, there's never a need to lower or cock the hammer over a live round. In fact there's hardly any need to touch the hammer at all.
A lightweight firing pin, and/or heavier firing pin spring, make the 1911 inherently drop safe. This is the approach Springfield Armory has taken successfully to its broad line of 1911 pistols. Adding a mechanical firing pin block safety can also work, and some other 1911 manufacturers have taken this approach.
This is because of how well most 1911s are balanced. When you've had a little practice with a 1911, the sights seem to just fall into place while the gun is in your hand, which is exactly what you want from your concealed carry self-defense pistol.
It's Easy to Disassemble/Reassemble
One of the best aspects of the 1911 is the ease of disassembling the gun. A simple field-strip or complete disassembly can be performed relatively quickly. Hopefully, the only time you'll need to disassemble your gun is during cleaning. The most important part to clean is the barrel.
In general 1911 was designed as a SERVICE gun (ie for police/military open carry). Its fine in that role, but it not a small pistol, weights fully 2.5lbs (ie 'half a brick') and I think most who want to carry concealed want smaller/lighter guns.
One particularly well-known technique of the IDF is carrying a defensive pistol with a full magazine but no round chambered. We call this empty chamber carry or “Israeli carry”.
The bottom line — a quality 1911 pistol with service-grade magazines and ammunition is as reliable as any handgun, more reliable than most, and more rugged than any I am aware. Other advantages include the speed into action of a cocked-and-locked handgun.
When seconds count, and you're in a home-defense situation, this is exactly what you want—especially considering the 1911's relatively limited magazine. The good news is that the 1911's 45 ACP rounds are renowned for their stopping power. If you hit your target, one is probably going to do the job.
Playing Favorites. The hammer-fired fans have as many reasons for their preference as there are options. The single-action fans have the short trigger stroke that can be adjusted to an even lighter pull weight than the striker-fired pistols, if desired, and a short trigger reset.
Hammer-Fired can Have a Loaded Chamber Without Being Cocked
With the hammer down, it's considered safe. Really, it gives peace of mind. carrying a pistol with a loaded chamber is becoming widely recommended by self-defense instructors and security professionals.
The 1911 is big. It almost always fires a big round, is made of metal, and was designed as a military pistol more than a century ago. And because of these things, it's also relatively heavy. Sure, a lightweight pistol can be easier to pack, and carrying a gun cocked-and-locked can scare off some EDC users.
Maybe the notion that the 1911 is the professional's pistol isn't deceitful. After all, many experts and professionals choose it. Regardless, what's blatantly false is that the 1911 isn't for beginners. If your firearms instructor tells you as much, find another one.
Accuracy. There's a reason why the 100-plus-year-old design continues to dominate competitive pistol shooting, and it's not its striking good looks. Among the most accurate pistols available, a match-grade Kimber, Dan Wesson or Colt 1911 easily print 2.5-inch, five-shot groups at 25 yards from the box, if not better.
You are right to be concerned about such things -- the 1911 is notorious for jamming frequently. Specifically the ejector mechanism; if the gun is not held steady after firing, the spent cartridge tends to get jammed between the barrel and the slide.
While you can always upgrade your trigger (and many Glock owners do), the stock trigger on a 1911 is consistently crisp and works slightly better for precision shooting than the Glock's. However, both triggers are accurate enough for close-quarters shooting, which is what you need in a self-defense weapon.
Magazine capacities
Standard (not extended) single-stack magazines, pistols based on the 1911 design commonly hold eight rounds or fewer. Many modern pistols have adapted the cartridge into double-stacked magazine designs to increase ammo capacity, though this increases the pistol's handle girth, but not width.
PROS: The 1911 Classic Features
Features like the grip safety (you have to be holding it properly for the trigger to operate) and the slide lock safety provided soldiers with quality guns that wouldn't accidentally go off and shoot their friends while moving through the trenches and in other battle scenarios.
Modern pistol designs have made the 1911 obsolete in its role as a combat sidearm. It's finicky and demands constant attention that a warfighter can't afford to offer. But when it's tuned and running well, it's the most accurate pistol out there. Warnings aside, the pistol's appeal is strong and romantic.