eli5: How does a gun backfire? isn’t there any mechanism in place to prevent it from happening?

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eli5: How does a gun backfire? isn’t there any mechanism in place to prevent it from happening?

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“for every reaction there’s an equal opposite reaction” meaning that when the bullet travels at those high speeds u are also getting the shock from it in the opposite directions, in theory u could say u are “getting a gun shot” also most of the times u still have gunpowder in the cannon and with the heat and/or speed of the bullet these can sometimes ignites making a second explotions inside the cannon.

Guns don’t really backfire, what they can do is fire out of battery which means the chamber is not closed all the way. Also if a bullet is manufactured incorrectly and too much gunpowder is added then the explosion can generate more force than the gun can take, this failure is more common in reloaded bullets and antique firearms.

What would you propose. Gun fires are chemical reactions which you can’t do much about. You don’t want anything that can fail and make the gun less reliable. Honestly the best thing to prevent backfiring is to make sure the gun is kept in good working order and jamming won’t happen.

A “backfire” is a car thing, where the spark is mistimed and so the force of combustion pushes the piston in the wrong direction… backwards. Backfire.

A firearm can have a number of failures, but I assume you’re talking about a catastrophic misfire, where the gun basically explodes in the face of the shooter.

A modern rifle cartridge generates pressures around 50,000-60,000 psi in the barrel. The firearm usually cannot handle these pressures for very long, which is convenient because the thing stopping the pressure from venting **is the bullet, and the bullet is moving very quickly to exit the barrel and let the excess pressure escape**. If the bullet cannot leave the barrel, that pressure stays in the barrel and typically does some kind of irreparable harm to the gun.

There’s a lot of pressure in there, and if it can’t find a hole, it’ll make one if any of the materials snap under the pressure.

When a gun is loaded, a cartridge (round of ammunition- bullet attached to shell casing full of powder) is inserted into the *chamber* (rear end of the barrel). It’s held in place in the front by the shape of the barrel, and in the rear by a part called the bolt. The bolt has to be snug against the back of the shell casing because when the powder explodes, it will push the bullet forward but also push the shell casing backwards.

The thin brass shell casing itself isn’t strong enough to contain the pressure of the exploding powder. The thick steel barrel which is snug around the casing and the thick steel bolt which is snug behind it reinforce the shell casing and keep the high pressure of the exploding powder contained. Only the bullet is able to move, and move it does.

However if the loading malfunctions, the cartridge can be loaded with the bolt *out of battery*. That means the bolt is not fully locked in behind the cartridge. So when the powder starts to burn, it will push the bolt back and push the shell casing out of the barrel. That leaves only the thin brass containing the high pressure (35,000 PSI or more), and the thin brass isn’t up to that task. Thus the brass breaks open, and you get a boom facing sideways or backwards. Or, the bolt is pushed backwards with great force and the rest of the gun shreds itself.