Upgrading HK416 Handguard

Looking at upgrading my handguard to the lonkest boi possible. I found this 11", with 35cm inner/outer barrels.

Am I correct in assuming I can use the stock gasblock/hop-up, and outer barrel adapter that sits at the base/receiver end?

I’m not sure about the stock gas block as I never had one from the beginning, i use the one from monkee mods on mine


I’ve been told that the stock gasblock will fit with Crux handguard fine, however most other handguards will require the gasblock to be trimmed down to fit in. But yes, the adjustable outer barrel will screw onto the end of the stock gasblock

post pics when you put it together ! i have a geissele handguard coming early next week for my HK

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I’m still a bit confused… The stock gas block has the gas block rod in a fixed position, as shown in figure A

And the gas block itself is fitted onto the end of the outer barrel, with a stop within the block, preventing it from sliding down the outer barrel any further as shown in figure B

So overall my question is, how am I going to make a longer outer barrel fit if the gas block rod only fits to this specific stock size? I’m so confused as to how I’m going to make a longer handguard work. I haven’t seen any tutorials on YouTube, either. So trying to explain it all through text is hard :joy:

Hey mate! Mind showing me a picture from a down-barrel angle? Curious to see how you worked the gasblock, or what you did to the hollow end of the handguard so it’s not just completely empty.

the crux at 11in is only half and inch longer than the stock one. should end up just before the thread so you can stick a flash hider on.
the gstyle forends can get at 14.5in". the gas block stays where it is on both lengths. the crux it is wide enough you dont have to remove the sling mounts off the block though. you just add barrel extensions on the 14ccw thread where the flash hider was.

if you add on extension pieces you lose the internal hopup ability though with that setup. be hiding it in suppressor maybe?

Yeah it all clicked in my mind as I was reading your comment, haha!

I was planning on slapping on a suppressor to cover up the hop-up :slight_smile:

Which handguard at 14.5" is compatible with the HK’s higher top rail?

monkee mods not stock atm. it will state for 416 and be gstyle or giessele as this one.

Damn I wish MM had it instock! D:

that one doesnt come with barrel nut and i dont know if compatible with the one on yours

Ah well. I’ll probably stick to the CRUX for now, and l look at a bigger one down the line. Or Just do a Gen9 DMR as my lonk boi


i spent around $100 on that forend plus barrel nut from alliexpress and a longer warinterest outerbarrel from monkee mods plus shipping and the rail is lower than the hawkexe 416d receiver. oh well.

Yeah it’s a tricky thing, having the top rail height a bit different

did a thread on it.

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What size inner barrel are you running on this set up? Also what size barrel extension and suppressor?

Looking at putting a stainless 7.3mm inner barrel and external hop-up hidden under suppressor on mine and am just trying to work out all my lengths i require?

It’s currently running 7.5 but not happy with accuracy, going to go down to a 7.3 shortly, the suppressor on the front is a tracer so cant rum a hop up in there so running one in the outer barrel

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Did you modify your gasblock and run a whole new outer barrel through the gas block or is it just a outer barrel extension screwed into the gas block?