Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian McCollum, and I am out at the range with an HK21.
This is the roller-delayed blowback system that is common to all of HK's early firearms,
the MP5, the G3, the HK33, the whole shebang.
And ... this is the belt-fed support machine gun version.
Now what's interesting about this is this was never a German Bundeswehr military weapon.
The Bundeswehr came out of the 1940s and 1950s with a magnificent support machine gun,
the MG 42 rebuilt in 7.62 NATO, and christened the MG3.
And the Bundeswehr never had any reason to get rid of that and replace it with anything else.
It was a great gun as it stood.
However, there were some other clients of HKs that didn't have MG3s or MG 42s
that did use the G3, namely Portugal.
Portugal is actually kind of instrumental in the development and the early marketing of this gun.
They had G3s and they wanted a support weapon that was based on the same platform.
So you get this. Early on the 5.56 and 7.62 guns were distinct and separate.
However, ... they put them together ... ultimately in an export version.
And what they did with that is they reinforced the receiver right up here,
and they made it a little bit longer than the 5.56 receiver.
And what they came up with was a universal modular receiver system.
So this receiver can be set up with either a magazine-feed assembly or a belt-feed assembly,
and it can get either of those in either 5.56 or 7.62.
So one receiver, you can swap out the feed unit, the barrel, the bolt, and the mainspring,
and have whatever configuration of gun you want in either cartridge.
So it makes for a really pretty cool modular system.
This does have a quick-change barrel, which is nice for an air-cooled gun like this.
We'll show you the barrel change system in a minute.
But beyond that you've got all the same controls as a standard G3 rifle.
You've got your charging handle up here, you got a fire control group, modular just like the rifle.
The standard on the export version of these guns
was a safe, semi, three round burst, and full-auto trigger group.
So we have mounted a pretty slick Trijicon VCOG on this guy,
and we're going to do some shooting with it.
So, loading procedure on this is actually kind of reversed from most machine guns
because in order to use the same style of stamped receiver as the G3 rifle,
this gun is kind of upside down compared to most.
And also of course to accommodate a magazine feed.
The feed is underneath the barrel, where on most machine guns you've got a top cover above the barrel.
So on most machine guns you want to see the top of the links when you load,
so that the brass is facing down into the action.
These guys are the reverse, so I have the brass facing up.
We're going to go ahead and feed that tab through, snap it through, there we go, two clicks.
The typical recommended thing to do is feed that through, and then charge it twice.
Basically charge it until you see a case spit out the empty side
to ensure that you've got a round chambered.
Yep. Alright, we are hot and good to go, let's give it a shot.
Everyone have ears?
We'll start with semi-auto, and see if I can hit anything.
Oh yeah, this is pretty easy to hit with. Let's try three round burst.
The thing kicks a bit, it's not quite as comfortable as something like a PKM.
... Well, it is a roller delayed gun.
So just like the G3 kind of has a reputation for being a bit harsh in recoil,
same thing with these guys and for the exact same reasons.
It's extracting and ejecting under relatively high pressure.
However, the side benefit of that is this is an extremely reliable system.
Let me go to full-auto unlimited. That's it, there we go.
Knocked my hat clean off.
Like the G3 rifle, these HK machine guns have really become a long-term staple weapon
with the military forces that choose to use them.
They have the same sort of incredible durability and reliability.
These are the sorts of guns that can be really sold to untrained, poverty-ridden conscript armies,
and continue to run reliably for decades despite horribly poor maintenance and care.
And because they have that same roller delayed blowback action of the G3 rifle,
they just keep running, and running, and running.
Does throw up a little bit of dust, doesn't it.
Knocked my hat off again.
Alright, that is a fair bit of ammo and that barrel's smoking pretty good,
so let's take a quick look at how we swap the barrel out.
Alright, now that we have got this barrel nice and toasty hot,
in order to change it, couple steps we're going to do.
First, we're going to hit the button here and drop the feed tray.
That just ensures that you don't have a round in the feed tray.
Then we're going to go ahead and lock the bolt open.
That of course ensures that you don't have a round in the chamber.
This is a closed bolt firing gun,
so when you stop shooting if it's ... not completely empty there will be a round in the chamber.
Then, being very careful not to touch this excruciatingly hot barrel,
we're going to push this button, rotate this up, and pull the barrel back and out of the action.
That, that, and forward, and out she comes.
Then, if I had a spare barrel here, I would slide it in, back, lock it down,
and then you're good to reload and continue firing.
So by the way, official HK doctrine is, unless you have a reason otherwise,
in order to charge these guns you slap that charging handle with all appropriate force.
The idea that you're not supposed to slap the charging handle on an HK,
that you have to be gentle with it,
that's urban legend from people who are a little too careful with their guns.
More so than necessary anyway.
Military doctrine is: smack that thing!
However, should you be in a situation where perhaps you are setting up an ambush and want to be quiet,
instead you ride the charging handle forward.
The problem with the roller-delayed system is when you do that, it doesn't tend to go fully into battery.
That is why HK has what appears to be a forward assist.
They don't call it a forward assist, and it's not on there like
you might have on an M16 to clear malfunctions (or to make them worse).
It's on there so that you can more quietly push the bolt that last bit into battery,
because of the mechanics of the roller-locking system.
But I don't have anyone that I need to worry about hearing me,
so wham!
Let's put some more rounds downrange.
I hope you guys enjoyed the video.
A big thank you to HK for letting me bring out one of their awesome
belt-fed 7.62 NATO machine guns to do some playing with.
Also a big thanks to Trijicon for giving us access to their range,
and use of one of their super high-end awesome VCOG scopes on this guy.
Thanks for watching, hope you guys enjoyed it.