I have heard the phrase many times, but I have never understood precisely what it meant.
So I turned to the magic of Google to do some research.
To my surprise, I found a range of meanings. Here is a sample:

"Lock and load" refers to “the procedure used for readying an empty M1 Garand for action, not because he said it backwards.
In order to prepare the weapon for firing, the bolt must first be ‘locked’ back to the rear so that the en bloc clip can be ‘loaded’ into the fixed magazine.
Once the clip is inserted, the bolt snaps forward on its own as soon as thumb pressure is released from the top round of the clip, chambering a round and leaving it ready to fire.”

“Locked and loaded” means “locking the magazine or cartridge into the gun and loading the ammunition into the gun’s chamber.”

“Lock and load” means “lock your safety and load a magazine into your weapon.”

“Lock and load” is “a military command to open the bolt of a machine gun (Lock Open) and load it.”

Urban Dictionary provides a definition that is mildly not safe for work and is in bad taste in any event.

https://www.lawfareblog.com/what-exactly-does-locked-and-loaded-mean

In the days before the M1 the command was, "Load and lock".

One had to load a bolt action rifle before the safety could be applied.

Attached File

I've always understood it as: "Engage the safety and chamber a cartridge."

I've understood it as WWII, Garand related; as in:  

It also is in reference to a Thompson M1 or M28?

Fires from an open bolt and to insert a drum (may apply to stick mags too) the bolt must be in the (cocked) locked back position. So Lock & Load.

I always thought it to mean to lock a magazine into the mag well then work the bolt carrier as to load a round into the chamber.

I thought it referred to carrying condition 0

With the rounds loaded wrong in the clips......

Lock your bolt to the rear, load a magazine/chamber a round. Seems simple to me.

Top round right!


I actually thought it might go back to muzzle loaders and other firearms that required the "lock" to be worked to get the gun ready to fire.  I.e. lock the flint lock back to half cock and load the primer charge and make ready to fire.   Sort of like where the saying "going off half cocked" came from.

This will bring forth the Sperglords.

Sho nuff.

It's what I tell the GF when I'm not using a condom

Today's meaning simply means ready to fire, or ready to go off.

Of course it is taken from many, many versions going back to the time of flintlocks. It's been around a long time, as long as we've had guns that must be loaded, and a firing mechanism with a locked position prior to being fired.