Anyone gotten or built theirs yet?
Anyone notice that mags seem a little loose in it? I've tried POF curved and HK straight mags and they don't seem to lock up very tight. Still waitibg on my side charger upper so haven't had a chance to shoot it.

I have the same issue. Mag is a little sloppy but I have not shot it yet to see if it is going to be an issue

I wonder what kind of mod would be necessary to hold the mag tighter? Maybe add material to the mag release pad?

Pics of build would be great, thanks

Update on my build. Even though the mags were a bit sloppy fitting in the receiver, it fed and functioned just fine

Glad its workin.. Got any pics?
I wonder if some extra coating in the magwell would tighten up the fit

Decided to tag this lower with one of my form 1 SBR tax stamps.

Haven't started milling the 80% billet yet, or received my barrel so this is just a mock up..

7" handguard
Side charging NFA C5 upper
80% C5 lower
Maxim buttstock
Magpul grip
A3 tactical modular foregrip with "grenade" grip
HK diopter sights

Will be putting a first gen Echo in it.

I have a CMMG Guard barrel/bolt (8") on order. I may have it cut and rethreaded. Maybe 4.25" not surr yet, but that length with a 6" can would be mighty handy.

If I cant get the Guard to run with the MP5 mags I will go a different route.

Anyways heres some pics

POF curved mag Attached File


HK straight mag
Attached File


Mags fit a little loose - NFA said they should fit snug once the coating is applied. Heres hoping.

does the rear sight work better backwards?

Looks great!  Love the curved mag look.  Hope they consider an EVO mag version.  Prices of EVO mags is much less expensive and MP5.

Love the MP5 but everything for it is just so expensive.

IDK I haven't tried it.. Ill let you know once I put some takedown pins in and can shoulder it.

What upper is that?

NFA C5 Side charger