Full Length Forend


@Flogrown The photo gets a bit blurry when you blow it up so give us the details. It looks like you used the Gen 1 forend from before and have bridged the sides with picatinny rails and the bottom with a Magpul or similar grip all of which should help stabilize it and also help with your long reach. Other than that, how is the underlying forend piece itself secured?
Love the Punisher cover on the charging handle. :smile: Did you make it or buy it?


@JoeFridaySays ya so the gen1 stock forend piece is secure to the barrel using the stock hardware that came with the original handgaurd. I attached 2 7" pic rails on both sides to mount a flashlight, laser, or both. The punisher logo on the charging handle is a DIY paint job. Personal touch lol


So what is stopping the gen 2 from locking when folded with the 420? Is the rail not allowing it to hinge far enough or is there just no catch on the end of the rail as on the stock forend has?

And JoeFriday, the 420 is mounted in a lower than center position as seen here


@ValorSolo … No catch.

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I know on the redlion, you have to leave one face of the rail housing ( it is centered, not offset)empty, so its probably rail contact. think it is the section closest to the tube retainer. you could machine a section to fit, probably. but then that would defeat the purpose of putting a full rail on top…


the top rail is not long enough to reach the slide catch at the rear of the butt plate.
If top rail was extended about an inch or so and then machined correctly it would lock.


A clamp on catch would be an easy fix for that. Sounds like something MCarbo could look into.
But by the time you add the price of the catch with the price of the forend, you may as well just get the red lion.

I’m still curious about the 420, may have to get one and play with it.

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I gotta wonder why you are so attached to a working catch? I cut mine off and I haven’t missed it a bit. When folded, I can pick it up by the forend or the bolt tube without it unfolding itself - note I generally grab the forend/bolt tube combo. So, I’m wondering if I’m missing some use for a catch that I remember as requiring a fine motor skill be inserted in front of the swing it open until the trigger guard locks operation.


LoL. The catch is actually a pain in the rear and I’ve thought of removing it myself.
The only reason I’ve been going through the process of retaining it is to see if I can.
I’m having a great time fooling around with all this until I can go back to work Monday.
Boredom kills, brother.


Thanks. That’s what I suspected, but I have never actually seen a 420 and needed someone to confirm.

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Here is my offering slightly modified. Remember the 420 was designed for a GENI.
this is a GEN II I am waiting for Good weather to shoot at 100yds.

Here is 5 rounds LAXAMMO 180 gr. reloads in about 2.8 seconds using a 3x scope that belonged on aTAVOR ( just look@ group).

Here is one mounted on a gen II ( slightly modified). A HELL OF A CARBINE

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I guess you know the 420 was developed for the GEN I. NOT the GEN II. The OEM standard fore end is different.
But not to fret ! as long as you keep the front clamp of the 420 on the larger diameter of the barrel it might work.
I REALLY DO NOT CARE !! It shoots on the GEN II with NO issue.

See the thread on S2K Fore end and find my posts there.

I would almost feel proud to sat the S2K might come to rival the Thompson in versatility !!


I’ll probably just stay with the stock forend. I kinda got tired of looking at the 420 and RLP.
If I switched it would be purely for cosmetic reasons, but I like the way it looks now.

I was just drawing out a barrel nut mod that some free float hand guards could clamp to.
It would have been a two piece clamp that went over the S2K barrel nut offset 3/16" from the top.
Allowing the owner to choose a 2" hand guard in whatever length and style they wanted.
It could be a feasible idea if there was a standard size free float barrel nut OD diameter.
The one I was drawing was 1.46" in diameter, and guessing the diameter of the S2K at .75".


Go For IT !
If you have the capacity to design/Draw/Build a fore end here is my thoughts.
If I HAD the funds or brains to design the “best fore end for the GEN II”.
have a top rail long enough to provide for attachment on a PIC rail that locked to catch near the butt end of the “stock” of the S2K with a bottom rail the same length. SAD TO SAY i do not have the capacity to create that reality.

All fore ends are going to have the “PERFECT” solution. BUT WILL FAIL!!!
In the perfect world you would have a new S2K “receiver” that would anchor a light fore arm. REMEMBER the 420 waas designed to be located onto the front of the GEN I !
Very similar to the 420 built with better anchor attachments (for the GEN II)
The 420 is a GOOD DESIGN ! but can be redesigned easily to make a MUH BETTER design for the GEN II
With all metal design just upgraded to GEN II that would take the 420 to the modern day !.

I have run 100 rounds in about 4.5 minutes and it runs HTH ( hotter than hell) The above pictures are testimony to the basic “perfect” design of the S2K plus all the work involved in making it the jewel it can be.


Basically this

Take two of these. Add a couple screw holes in the thicker section.
Makes a clamp on block that the hand guard would then clamp on to.
There is a small ridge on the S2K barrel nut that a groove needs to be made for.

I may give it a try in TPU when I get my printer.

EDIT: Of course you would need to get proper dimensions from whichever hand guard you choose to use.


Just mounted the 420 to my Gen 2 and so far I like how it looks and feels. Just need to figure out a flip out mount for my red dot, so I can fold it.


I have my new printer. I’m running it right now. I’d like to share the STL files if anyone is interested.
This is a huge learning project for me. First time with CAD and first experience with 3D printing.

Maybe we should have a 3D thread all on it’s own. I’m sure there are a lot of great ideas out there.

Anyways, this is a two piece adapter that allows the use of free float handguards.
The inner part should remain the same, if I designed it correctly, for all 9MM.
The outer dimensions will need resizing depending on the inside diameter of the forend.
I’ll post the results in a few hours when it’s done and I’ve checked the fit and finish.


Can’t wait to see. If it works I would probably switch out my 420 to a free float.


So my design was slightly off, hence the gap in the bottom picture.
But that would actually work well for a clamp on hand guard.
I don’t currently have a spare clamp on hand guard to test it.
Nor do I feel like removing my front sight.

Great experience gained, however, so I’m happy with the results.
The print quality could have been better, but I had it set low for speed.
Still took an hour for each piece.



Amazing research and valiant effort to follow your dreams of building the perfect SUB-2000 for your own personal liking!!! Also the funds to follow one’s heart??? :+1::+1::+1: