Combat rifle scopes and a backup plan
When you mount your rifle scope, please do some research on how to properly level and mount it. A properly mounted combat optic should not be over torqued and should have loctite on the screws. I have yet to see a mount come loose on a gun that used loctite. When you go out an spend $1000 on a combat rifle scope, ask yourself, what will you do and how will you remove the scope and aim it if the optic goes down. If one your Trijicon rifle scopes takes a bullet, are you going to be able to see through it and still be able to lay down effective fire if you can’t see through it? Even if you have a rifle scope that does not allow for co-witness, would it be a good idea to still attach flip up sights to the gun if there is room for them? Always have a backup plan for your defensive carbine.
The vast majority of M4 Carbines I see at the range have optics that are top of the line. Aimpoint and Eotech along with the Trijicon ACOG are probable the top 3. All of these are good for a certain purpose which is mostly for close up fighting. The Trijicon ACOG is more of a medium range combat optic depending on the type of reticle you choose. They do have a line of red dot or even green dot optic options, also. If you are are a weekend warrior and new to defensive shooting and tactical gear, I would suggest you think about this next statement, whenever you attach an accessory to your Carbine, think about what you would do if that accessory mount broke or the actual item failed.