When Heckler & Koch produced the iconic G3 rifle, it was intended to be a parts of a complete small arms package. The G3 was the infantry rifle, and it was paired with the MP% submachine gun and the HK21 light machine gun for a complete set of weapons with the same manual of arms and disassembly/maintenance procedures. The first client for H&K was the West German Bundeswehr, and they were not interested in the HK21 – they had the MG3 already and were quite happy with it. Instead, Portugal would be the most significant early buyer of the HK21.
Mechanically, the HK21 shares all the same general principles of the G3. However, it has elements strengthened or modified to suit an LMG. These include a reinforced receiver, heavier recoil buffer, better long-range sights, and of course a quick-change barrel and a belt feed action. While an insert was made to allow use of G3 magazines in the original HK21, this was not a common practice. The receiver did not have the modular features that would come later on iterations like the HK21E; this was a gun really intended just for belt-fed use in 7.62x51mm NATO.
The HK21 was introduced in 1961, and Portugal adopted it as the m/968. Portugal actually purchased a license to produce the gun, and this particular example was one of many made at FMP in Portugal. The gun weighs 17.5 pounds (7.9 kg) and fires at 800-850 rpm. It is a relatively difficult gun to use well, with a comparatively harsh recoil for guns of its type. It did compete in the US LMG trials, but lost out to the FN Minimi.
Special thanks to Bear Arms in Scottsdale, AZ for providing access to this rifle for video!
Another big customer for the HK21 was the West German Border Guards (Now Federal Police), who for example used a stockless HK21 on their light armoured vehicles that replaced the Saladins in the 1960s/70s
In several West German states the HK21 was also purchased for the “Bereitschaftspolizei”, state level police units used for example for riot control and such. I doubt they were ever used in actual duty though…
German police leadership, always keen to show their political correctness to the
do-gooders, had the HK21 designator changed to G8 (Gewehr 8) and the stated purpose to precision rifle.
US Navy SEALs did use them a bit as well in Vietnam. Ive also seen pictures of the S African forces with them during the border war.
I’ve never heard any first-hand reports from the Portuguese about these.
I have heard first-hand user reports straight from the Special Forces weapons sergeant’s mouth, and they all universally described them as the biggest POS they had in their modern foreign weapons arms rooms. Why the hell that would have been, or what the provenance of the weapons they had experience was, I have no idea. I just know that they all hated them. If I remember what they said about it correctly, the root of the problem that they had with these weapons stemmed from the relatively tiny stud interface with the bolt that ran the belt feed system; the receivers were prone to stretching just enough that the bolt would override or the stud would pop out of the track, leaving you with a rather nasty jam. What I don’t remember was whether these HK21s that they had in their arms rooms were the early ones like this, or the later ones with the more modular receivers.
This is one of those lesser-known weapons whose reputation isn’t exactly certain, in my eye. You have a bunch of people who didn’t like it, it didn’t sell well, but… You aren’t certain you should trust what people are telling you about it, and you can’t just get one to take out and then wring out for yourself to learn whether or not what you’re being told is justified.
I have heard several people who thought they were great guns, but when I looked into their backgrounds, they were usually people who did more “carrying around with them than “using in combat”. If a Vietnam-vet SF weapons sergeant tells you something about a weapon he’s got a couple of thousand rounds through, well… You can usually take that to the bank. I understand that SF bought a bunch of these to evaluate, because that was back in “ye olde dayes” when the M60 was basically the only thing going for a ground-mount MG in the US military. The evaluation did not go well, from what was related to me: “Overpriced German junk” was the kindest thing said.
Again, no personal experience, just what I was told. Your mileage may vary, and all that…
FWIW, I fired one. once. Nkongo base, SWA. A Koevoet Callsign was passing through and they had one. I, being a gun guy, expressed an interest in it. A Koevoet NCO, with a certain taking the tenderfoot on a snipe hunt air about him set me up to shoot it. Two things stick out in memory. One, it was an exceptionally unpleasant firearm to shoot, like holding an air chisel to your shoulder unpleasant. Two,it had the exact same sights as a G3 rifle. I don’t care for those sights at the best of times and with an earthquake in your arms they became totally useless. They offered to trade it straight across for an MAG (Ha. fat chance!) or a case of beer so I gathered that it was an noninventory piece, but where they got it I cannot, at this date, recall.
That must have been a leftover from the Portuguese in Angola… Presumably.
I always thought that HK had a bit of madness going, in that they wanted to apply roller-delay to everything under the sun, without heed to whether or not it was really appropriate. They really carried it all out to the ridiculous extreme; you rather expect to run across HK roller-delay sewing machines and espresso makers.
It’s rather as if John Moses Browning decided to apply his parallel ruler mechanism for the original Colt pistols to everything from the 1911 to the BAR to the M1917… Some things just don’t work universally, I fear.
“(…)apply roller-delay to everything under the sun(…)”
I would not call this madness, but rather Einstellung, see https://en.wikipedia.org/wiki/Einstellung_effect
That’s funny, but I think it makes a lot more sense in context / chronological order.
HK went from trying roller-delay in its sensible original (intermediate) application, to being forced to apply it to the marginal / still-acceptable case (G3) by US NATO standardization. Their return to intermediate (5.56) cartridges was flawed but not unreasonable in light of previous experience. They found the system’s ideal niche (9mm) reasonably early in the process, then ran with that to produce the even more logical SD and K versions.
HK had its first design adopted 65 years ago and produced the “ridiculous extreme” HK21 just two years later, but came to focus and successfully iterate on their best product for the majority of the company’s history.
The same guys under a different management already experimented the roller delay mechanism both with intermediate and full power cartridge, and it would have surely been put into mass production had the war lasted a bit longer.
Roller delay is practically ideal for a full power cartridge GPMG. And infact the Swiss repeated the entire process, without having the original blueprints for the SIG MG710-3, that solved the two main problems of the MG42/MG3, weight (being more than 2kg lighter, under 10KG in total) and length (more than 8cm shorter for the same barrel length).
P9S, anyone…?
That was what I was thinking of, when saying that HK took the roller-delay a bit too far.
I’d also question anyone saying that the higher-pressure rounds like 7.62mm NATO and 5.56mm NATO do well with that operating system. I’ve always found the G3/HK91 to be a bit much of a muchness, with regards to recoil and general filth. If I had to pick an ideal operating system for that cartridge, I think that the various iterations on a theme that is the AR-10 would probably be the best I’ve handled so far.
I’d agree that the roller-delay thing is best implemented with an intermediate caliber of low pressure… 7.92X33 and 9X19 doing very well with it all.
Friend of mine has a cobbled-together HK93 clone that he managed to make work in 7.62X39, and he swears by it as the bestest thing ever… I suppose he might have a good thing going there, but I reserve judgment on the concept, given how long it took him to work it all up. I mean, I think he started in on it back when you could get cheap milsurp 7.62X39 by the boatload for relatively small change, and he only got it working after about 15 years of screwing around with it… By which time, the grounds for the idea had quite evaporated because the prices on ammo had gone through the roof.
@ Kirk
What I heard from people that visited some serious shithole is that the G3 is the AK47 of the western rifles. None likes its ergonomics but, battered, rusted, thrown under a truck, it’s the last gun that still works.
5.56 is notoriously picky, but I don’t see the problem in using the 7.62 with delayed blowback actions. The pressure is not even that much higher than 7.92 Mauser and, as said, also the Swiss used it (MG710-3 and SG510-4).
“(…)only got it working after about 15 years of screwing around with it(…)”
That itself does not say anything without knowing hours working spent.
“(…)7.62X39(…)”
According to http://modernfirearms.net/en/machineguns/germany-machineguns/hk-21-i-23-eng/
The HK 21 spawned a whole range of modifications and derivatives. Other than the basic 7.62mm NATO caliber, HK also offered its machine guns in(…)Soviet 7.62×39 chambering.(…)It must be noted that HK never manufactured weapons in 7.62x39Soviet in any significant numbers(…)
So they considering such weapon fit but there was little interest from potential customers.
“(…)question anyone saying that the higher-pressure rounds like 7.62mm NATO and 5.56mm NATO do well with that operating system.(…)”
If you want to use said operating system AND not use 7.62mm NATO AND not use 5.56mm NATO then use HK25 https://firearmcentral.fandom.com/wiki/HK25
Y’know… I’d forgotten about that one, Daweo. I’ve always wondered if that wasn’t a bit of a practical joke by HK, because that cartridge in something the size of an HK21 would have to be seriously damaging to just about anyone’s shoulder..
To me the madness (even if justified by the fact that there was a demand for it) was trying to turn an infantry rifle into a belt-fed MG. That the rifle was roller delayed is what made this operation even thinkable, since the system has some advantage, IE in recoil management. A belt-fed FAL would have not fared any better, and probably much worse.
FN FAL was not subjected to such treatment as far as I know, but AR-10 was
https://www.thefirearmblog.com/blog/2016/04/29/1950s-embodied-ar-10-converted-belt-feed/ by Artillerie-Inrichtingen but did not find customers.
I have read that the initial HK21 Metralhadora M968 MGs made at Fabrica BRAÇA de Prato/ FBP factory had considerable, erm, uh, well, “teething troubles” in actual service during the Guerra Colonial/ Guerra do Ultramar. Recall that when the “Estado Novo” doubled-down on colonialism after its use-by date, being largely unable to emulate the UK and France in assuring their interests after the hand-over to compradoor “home rule” regimes, the Portuguese armed forces had bolt-action 8mm rifles, some very dated 6.5mm rifles in African colonies, Metralhadora Madsen M/930s, Metralhadora “Dreyse” M/938s, the Breda M/938, and so on. The Estado Novo cagily threatened Nato access to the Azores Island bases to overcome most Western European and eventually, post-JFK, American resistance and with considerable assistance from West Germany, obtained the manufacturing rights and technological package from Hochler u. Keck in Oberndorf am Neckar to manufacture the Espingarda M/961–G3, and M/983 G3 with collapsible stock. They were also bequeathed the ex-G1 FAL as the M/962. The AR-10 was subject to arms cut-offs by less unscrupulous Nato nations, but was used by parachutists/ paratroopers, which, as in German practice, were part of the air force. The HK21 came much later in the wars.
As a matter of fact, I encountered FMBP marked G3 rifles during my Bundeswehr service. In my expercience they worked as flawlessly as the others. Bundeswehr G3 manufactured by Kongsberg and Rheinmetall (marked with the respective logos) were the same.
Wait… What? Portuguese- and Norwegian-produced G3 rifles were on issue in the Bundeswehr? Rheinmetall I knew about, but the other two?
Man, I’d almost demand documentation if someone else were telling me that. It sounds like, on the face of it, something like the old soldier’s story about Mattel M16 rifles…
I wonder how the hell that even happened, because I’ve never heard of such a thing, and the various HK documentation sites I’ve seen show no exports back to Germany from either Norway or Portugal.
I wonder if those might have been HK-produced weapons that didn’t get exported to the respective countries and which got shipped off to the Bundeswehr instead…?
Who knows? Perhaps things get confusing during particular Nato military exercises? My comments on unreliability referred specifically to FBP Portuguese-produced HK21s/ Metralhadora M638s, not the G3 rifle. Certainly some Portuguese G3s have gone to Ukraine.
I note that its Spanish CETME predecessor used a lower-pressure 7.62x51mm cartridge before Nato standardization, which may have entailed some kind of modification? And, also, the Japanese Howa Type 64 select-fire service rifle/ automatic rifle. The Japanese gun had a gas-setting for full-strength 7.62x51mm ammunition.
I believe many of the G3s transferred to El Salvador after the so-called Fútbol/Soccer War against Honduras were Portuguese, no? Rhodesia and SADF got some for sure. Certainly these were also made in Iran under the Shah and after, Greece, rival Turkey MKE, Saudi, POF Pakistan, SEDENA Mexico [the most I’ve seen “in the wild” so to speak], formerly Indumil Colombia, Kongsberg Norway, AK4 Sweden–going to Estonia these days, MAS and Manurhin in France?, Nigeria, and even Burma/Myanmar too…Maybe Thailand as well? Or is that just the HK33? I’m still startled on the Forgotten Weapons episode when the intrepid Mr. M’Collum revealed that Denmark *leased* its G3s from the Bundeswehr!
Kirk, you possibly know of the childhood method of making an image of a rough surface (coin, for example) buy laying a sheet of paper on it and then carefully rub a soft pencil over the paper?
This is what I did (during endless shifts on guard) with several G3s (HK made in 1/65, Rheinmetall 1/66, FMP 5/68 and Kongsberg 10/65) and the resulting sheet of paper is in from of me right now. I was in charge and nobody questioned the authority of a 2nd Louie.
I am not aware of any way to place an image here. But send an email to bkk14(at)jochempeelen.de and I will send you immages of the “pencil art”.
(Spammers relax, the above is not my everyday email address.)
It should have been: “the resulting sheet of paper is in front of me right now”
In view of German cold war machine gun philosophy (high rate of fire), the HK21 as well as the SIG710 suffered from only being able to achieve a much slower rate.
The so-called MG45 of WW2 also fell in this category, presumably because it could not achieve anything faster without burst cases.
WW2 military requirement for an MG42 successor remained “at least as fast as MG42” (Bundesarchiv document from late 1944). The MG42/MG3 family also uses rollers, but in a very different design, as locking elements of a short recoil mechanism.