What are the firing modes of these weapons?
As long as I know the M4s is safe/semi/burst. If this is true, what happens if I pull the trigger and not letting it ago?
And the M4A1's safe/semi/full auto, am I right?
I'm not sure how the M4 series is set up now, last time I checked they were usually full auto, with the standard M16 rifle version having the burst fire system.
The burst system has a "cog" counter device in it.
When the trigger is pulled, the weapon fires 3 rounds in a burst.
If you just pull and hold the trigger, the weapon fires 3 rounds and stops.
You have to release the trigger and pull it again to fire the next burst.
One "oddity" of the cog wheel burst system is, if you release the trigger BEFORE all 3 rounds are fired, the weapon will fire 1 or 2 rounds.
When the trigger is pulled it will fire the remaining rounds.
In other words, if the weapon fires 2 shots and you release the trigger, when you pull the trigger the next time, it will fire 1 shot.