Will a Daniel Defense low profile gas block fit under a Geissele Mk4/8 rail?

[Skyyr]

As the title states. This is regarding the set-screw Mk12 version, not the clamp on.

Bonus question: What about an VLTOR low-pro block? Will it fit?

[Iraqgunz]

Almost anything will fit under those rails. I have a Geissele block under my MK4. BCM works, as does Vltor, etc..

[Waylander]

The DD MK12 is known not to fit under certain rails. I'm not saying it won't fit under this rail but to be safe I would get the Vltor or BCM.

[ncmavro]

Not sure, but something to consider is that the mk4/mk8 ships with a geissele lo pro block if you buy it new from a retailer, not sure if that applies in this case though.

[TNW]

Not sure, but something to consider is that the mk4/mk8 ships with a geissele lo pro block if you buy it new from a retailer, not sure if that applies in this case though.

I had a MK4 on a DD MK18 upper and it was good to go.

[Iraqgunz]

The MK12 block is a low profile design and smaller than a Geissele block. The MK4 and MK8 internally are like the Carlsbad caverns.

The DD MK12 is known not to fit under certain rails. I'm not saying it won't fit under this rail but to be safe I would get the Vltor or BCM.

[Waylander]

The MK12 block is a low profile design and smaller than a Geissele block. The MK4 and MK8 internally are like the Carlsbad caverns.

That's fine but the MK12 is larger than many standard low pro gas blocks. If OP is sure he wants to stick with this rail no problem. I would just get the Vltor or BCM and be done with it.

I know from first hand experience with it not fitting under a URX 3 rail and this.

https://www.m4carbine.net/showthread...veske-NSR-rail

You are absolutely correct and we do build it per the TDP specifications. We are currently a supplier of the MK12 LPG to the military as well as offer them commercially. Because of the wide flat bottom of the block, it won't fit under a lot of free float handguards. Ours included. On our RIS II rail system, we machined slots in the bottom rail to accommodate the block when installed on a carbine length gas system barrel.

For anyone who's interested, we do offer a clamp on style gas block as well. It fits under most handguards on the market.

S/F
Joe