If you notice both the M-4 and the AR-15, there is one common difference. AR-15 Vs. M4 is one hot debate to look out for.The M-4 is a fully automatic weapon that is available for only the armed forces. When you compare both the AR-15 and the M-4, you can notice that the barrel size alone differs. Many people are seemingly interested in theAR-15 vs M-4 war.The AR-15 is known to use a 16-inch barrel. But when you see the M-4, it contains a 14.5-inch barrel.

So what are we trying to do here? This really feels like a bot... I’m in Mobile format, so is there a spam link in the signature line or what? Between this one and the SBR vs. pistol vs. rifle thread this week, I really feel like these are just bots... otherwise it’s information which can be found a thousand other places online, and in better detail with less ignorant half-truths.

M4’s, M4A1’s, Commandos, etc are standardized model designations which include specific components - like barrel length - but for the civilian AR-15, the sky is the limit. I’ve built and rebuilt over 600 AR’s and uppers in the last ~20 years, with barrels from 7” to 29”, in a couple dozen cartridges from 17 Remington to 50 Beowulf... the possibilities for the civilian AR-15 might not quite be endless, but it’s pretty damned close.

I'm thinking a bot or somebody who doesn't know very much about the 2 systems.

An M4 is just a specific type of M4.

The OP's question is honestly meaningless.