MCR and WK - piston compatible handguards

[Morc]

For compatibility with the WK and MCR would the following be considered a reasonable rule of thumb as a starting point to determine if an AR15 handguard will be compatible.

- Handguards advertised as compatible with low profile gas blocks only are not compatible
- Handguards advertised as compatible with piston driven ARs have a high probability of being compatible (assuming no unusual barrel nut design)

 

[bleaches]

- Handguards advertised as compatible with low profile gas blocks only are not compatible

Not always the case.

- Handguards advertised as compatible with piston driven ARs have a high probability of being compatible (assuming no unusual barrel nut design)

99% of the time true. The other thing you have to consider is because the WK has a rectagular box of a upper receiver. If the handguard has two anti rotation nipples on the receiver side that indexes below the picatinny on the upper, you might need to grind those off.

Eg. DD RIS II has two tabs that pinch the upright face on the upper receiver just below the rail.

 

[Morc]

Interesting, thanks for the info.

I've been told that the BCM MCMR handguard is not compatible. It's stated as only compatible with low profile gas blocks so I made the assumption that was universally true. Sounds like not always.

Something like the Fortis Rev 2.0 rail has the clearance for the WK/MCR piston as it's advertised as being piston compatible but does appear to have the anti-rotation tabs like you mentioned.

 

[bleaches]

Interesting, thanks for the info.

I've been told that the BCM MCMR handguard is not compatible. It's stated as only compatible with low profile gas blocks so I made the assumption that was universally true. Sounds like not always.

Something like the Fortis Rev 2.0 rail has the clearance for the WK/MCR piston as it's advertised as being piston compatible but does appear to have the anti-rotation tabs like you mentioned.

The Fortis Rev 2.0 should work fine. You will probably have to dremel a bit of clearance for the piston rod on the barrel nut because the flanges are made to clear gas tube diameter only.

 

[bleaches]

I personally went with one on Aliexpress that appears to be the same as the ones TNA sells well before they started selling them. I thought. It's dirt cheap so why not. And it worked perfectly.