M4A1/CQB Upper - Block I vs Block II Rails

[Son of Dorn]

Those of you who have M4 and/or Mk 18/CQB clones, which do you like better? "Classic" Block I with the KAC rail, or the newer Block II with the full-length Daniel Defense rail and the low-profile gas block? Or do you like the DDM4 rail with the front sight cutout like the interim versions, or what? And most importantly, why?

 

[nn8734]

Those of you who have M4 and/or Mk 18/CQB clones, which do you like better? "Classic" Block I with the KAC rail, or the newer Block II with the full-length Daniel Defense rail and the low-profile gas block? Or do you like the DDM4 rail with the front sight cutout like the interim versions, or what? And most importantly, why?

I’ve had clones with both KAC RAS and DD RIS and turned my mk18 Mod 0 into a Mod 1 with the DD RIS II rail and DD 10.3” mk18 barrel. I much prefer the low profile gas block out of the way and additional rail space the Block II/Mod 1 style rails provide. No front sight post in the way of my optic (flip up front sight is there if I need/want it). Can extend my support arm a bit further which is more comfortable for me. Same goes for my DD M4A1 Block II. Lastly, aesthetically speaking, the block 2 DD rails just look better to me.

 

[Son of Dorn]

I’ve had clones with both KAC RAS and DD RIS and turned my mk18 Mod 0 into a Mod 1 with the DD RIS II rail and DD 10.3” mk18 barrel. I much prefer the low profile gas block out of the way and additional rail space the Block II/Mod 1 style rails provide. No front sight post in the way of my optic (flip up front sight is there if I need/want it). Can extend my support arm a bit further which is more comfortable for me. Same goes for my DD M4A1 Block II. Lastly, aesthetically speaking, the block 2 DD rails just look better to me.

The DD rails do look nice and I like the extra real estate. But I also like the front sight post for some reason. Maybe not having to worry about it getting lost, maybe it just sets the carbine apart from the myriad other ones without them, maybe I'm just too much of a traditionalist that I want to keep it.

 

[nn8734]

The DD rails do look nice and I like the extra real estate. But I also like the front sight post for some reason. Maybe not having to worry about it getting lost, maybe it just sets the carbine apart from the myriad other ones without them, maybe I'm just too much of a traditionalist that I want to keep it.

Yea, irons are definitely more of a personal choice. I occasionally use mine just to challenge myself and keep up with them but for the most part, I like the ability to fold them out of the way and keep sight pic through the optic unencumbered.

What sort of optic will you be running? I know with LPVOs the fsp appears as a sort of smudge or streak in the sight picture while the front post can be used in conjunction with the rear sight to effectively co witness with the non-magnified stuff.

 

[Son of Dorn]

Yea, irons are definitely more of a personal choice. I occasionally use mine just to challenge myself and keep up with them but for the most part, I like the ability to fold them out of the way and keep sight pic through the optic unencumbered.

What sort of optic will you be running? I know with LPVOs the fsp appears as a sort of smudge or streak in the sight picture while the front post can be used in conjunction with the rear sight to effectively co witness with the non-magnified stuff.

Flip-flopping between an Aimpoint of some sort or another (M3, PRO, M4) and an Eotech, maybe with a magnifier.

 

[Jackalope]

I like a fixed front sight base with a RAS. It’s a time tested setup that’s pretty much indestructible. You also get the option to retain a full set of irons. I don’t even notice the front sight when shoot through the eotech.