Is this common movie device actually a good idea, or are you more likely to get a ricocheted bullet in the gut for your effort? What about padlocks? Metal doors? Is there a safer and/or more effective angle to shoot from? Not that I have plans to shoot open any locks any time soon, I’m just curious.
It is possible to safely open a door with a gun, if you have the right equipment. Police SWAT teams use shotguns with specialized ammunition and stand-off devices.
A stand-off device is sort of like a dull bayonet which keeps the shotgun the proper distance from the door. Putting the muzzle directly on the lock to be blown is probably quite dangerous for a number of reasons which are easy to imagine - the pressures inside the barrel could be really; flying debris could damage the barrel; the barrel could move in unpredicatable directions. On the other hand, just aiming the gun at the lock could result in a miss; you probably want to keep your head away from the weapon itself, rather than aiming it like normal.
The ammunition is designed to disintegrate harmlessly a few feet on the othe side of the door. You never know if someone is vulnerable on the other side of the door, and could get hit by a penetrating bullet. I suppose debris from the lock itself could injure someone on the other side of the door, but the correct ammunition makes the whole operation as safe as possible, and blasting a lock isn’t a decision to be taken lightly in any case.
So basically, I’d say that door breaching can be done relatively safely (not that SWAT operations can be expected to be perfectly safe) but that as portrayed in fiction, blowin the lock off is anything but safe. (Then again, leaping from a helicopter onto a moving train while being shot at by a dozen gun-running white-slaver cyborgs is pretty dangerous as well.)
Pretty much what Boris said.
A lot depends on the lock.
A cheap padlock can be blown apart from a pistol, but the more expensive padlocks can definitely survive a bullet from a pistol (I have seen some).
As for the lock on a wooden door. Again, a lot depend on the lock itself and a little bit of luck. A decent deadbolt is unlikely to be dislodged by anything short of a breaching shot from a shotgun (see Boris’ post above). A lock which simply prevents the handle from turning could certainly be damaged from a pistol not so much by shooting the handle, but by damaging the area around the locking mechanism itself so that it can simply slide free.
As for metal doors. Again, a lot depends on the caliber and the bullet. Some bullets (full metal jackets for example) will be able to penetrate the metal. Others will be much less successful. Again alot depends on the weapon too. Many rifles can fire a projectile with enough force to penetrate an car (both sides), and would have little trouble shooting through a door. Clearly, a metal door is going to provide a lot more protection from deformation then a lock in a wooden door.
Master lock used to air a commercial that showed one of their locks being shot with a high-powered rifle (I believe a .308). After the shot, the lock had a hole drilled through it, but it still held.
A handgun round probably wouldn’t even penetrate a solidly built padlock. But you might be able to destroy the other parts of the lock mechanism, or enough of the door frame around the lock to pull it through.
But it would most definitely not be a guaranteed technique. That’s why SWAT teams use battering rams, or even go to the extreme of using det cord to make a NEW doorway.
I am a Mechanical Engineer, and (thought) I knew exactly how strong a Master padlock was. And how powerful a shotgun blast was.
An acquaintance once showed me how he was going to blast a brand-new Master lock off of a barn door that he had. He had lost the key, and I thought he was just being really macho. I was prepared to start laughing in open mockery as the shotgun scatched the finish on the lock, leaving it mostly unharmed.
That’s not what happened.
He shot the lock once with a 12-gauge, from about 6 inches away. This super-tough Master lock exploded into shrapnel. The largest piece I found was the hook (the U-shaped steel bar) - everything else was in small pieces.
I was, and still am, dumbfounded. I would have bet $1000 it would not have broken the lock - and to absolutely shatter it - I have no idea how, but I did witness it. I really cannot tell you how it did it - and yet, it did.
Maybe he was just playing with you. A guy I knew said he would just alternate Liquid nitrogen and a blowtorch to fatigue locks until he could break them with a hammer. Maybe your friend just grabbed the shotgun for extra effect. You would probably know better than me how fatigue resistant a lock would be. Anyway you have just given me a new project for some weekend. 
Not this guy - he was hazardous, but not smart enough or resourceful enough to do this. Plus, he just did not make any big deal about it at the time. I suppose it’s possible, but…I don’t know. I just don’t think so.
well the Master lock was shot with a bullet in the ad which is 1 single slug. A shotgun with some strong ammo shoots pellets which is the equivalent of a hundreds of little slugs. So there may be a arguement that shooting it with a shotgun is like blasting the lock over and over.
Of course, it depends on the ammo too. There are some brands of shotgun shells called “Shredders” and others that are absolutely capable of doing as they are named…namely shredding anything, including a lock.
Having used alternate means to gain access to secured places a time or few myself, here’s what I’ve learned:
First, padlocks, especially older models, aren’t nearly as tough as most people think. Many times on older locks all you need to do to open them is to rap them sharply on the bottom with a hammer or mallet. This leaves the lock completely intact, and you can resecure it when you leave. This trick used to work great on old forest service access roads, for example. I’ve also been witness to numerous incidents where Master locks tried to stand up to a Rawlings aluminum bat, and lost after a single whack; thereupon being reduced to (damaged) original components.
As far as deadbolts go (most other types of doorlocks are worthless), it depends a LOT on the manufacturer. In most cases, though, shooting just the lock will not be enough. The BOLT is what’s keeping the door closed, and that is what needs to be disabled. Many police agencies use a type of 12ga shotgun round called a “doorknocker” for this purpose. Essentially, this is just a standard round packed with a heavy load of #12 or smaller shot (basically lead dust for the firearms-impaired). The kinetic energy of each piece of shot is VERY small, and the effective range is therefore just a couple of meters, but the overall effect of hundreds of these very tiny pieces of lead hitting all at once will tear the lock/bolt combination from the door/frame quite nicely. High powered handgun rounds will also work, but they are harder to put precisely where you need them, and it usually takes succesive (2 or 3) rounds to work.
Does Hollywood exaggerate the effect and how often it’s used? Yes, without a doubt. Does it actually work in real life? Again, yes, but it is best left to the pros.
E-tools work better for padlocks anyway.
Leaving the realm of law enforcement, my infantry manual for combat in built-up areas (title freely translated) recommends 8-10 rifle rounds in a half-circle around the lock, followed by a swift kick, for an outer door. The rounds should be fired at an angle to prevent ricochets if one hits metal parts or the lock itself, but standing in front of the door is bad technique, anyway. I’ll admit that it sounded like serious overkill (it’s a lot of ammo to do without) to me, but they’d been doing tests.
S. Norman
If you really need to get a door open without a key, the best way to do this is with an oxy-acetyl torch, known in the trade as a “Victor Wrench”
I must respectfully disagree with this in some cases. A cordless Dremel rotary tool with cutting head can cut through the hook of a Master or any other brand hook-type lock in about 30-60 seconds, and causes no collateral damage at all to the door and surroundings. A very useful device, for cutting through virtually all metal - albeit slowly.