The M60 light machine gun is something of a contentious subject. Many veterans who used it in combat in Vietnam remember it very fondly despite its design defects, while many more recent users detest it. I think I know why – because many of the M60s flaws were related to its long-term durability, so that newly made guns in the 1960s performed well, and the problems didn’t start to crop up until the guns had seen years or decades of hard service.
With that in mind, today we’re taking a look at a modern updated M60E3 at the range, courtesy of Scott at Hydro Print Services. He also shows us how to properly shoot it, after I demonstrate my impressive inability to hit the targets. 
Exciting reactive target provided by In The Red Exploding Targets. Check em out – cool folks and a great product.
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Actually, the Vietnam era nickname for the M60 was ‘the Hog’. Southern American slang for anything big and heavy…
Back in 2000 I was trained to clear, disassemble, re-assemble, conduct a functions check and maintain an M-60. The poor guns were falling apart. Our upper class and prior service cadets that had to carry and use them relayed many of the same issues that you illustrated. I just remember having to tie down the “Jesus Pin” and trigger assembly. Bailing wire was provided. Ranger School had a whole tie down procedure for the M-60 because of Trigger Groups losses. Luckily, that summer we turned in the M-60 and unboxed brand new FN M-240. Cadets are good at wearing out weapons! Most of our M-249 SAWs were trashed and our M-16A2′s were “transformed/reworked” A1 lowers. The USMA Museum in Highland Falls NY has a prototype M-60 if you ever head east…
The safety wire tie on the pin goes back at least to the 1970s. Only an armorer (or 18B/11BxS) was supposed to R&R that, and he had the safety wire pliers (a tool you can get from aviation suppliers). I don’t think it was originally part of the design, the spring clip was supposed to do the job. Just one more deficiency resulting from the incestuous idea of having the same guys do all phases of RDT&E on their own design without any IV&V.
In those circumstances, things go nonlinear fast unless your designer is John M. Browning.
Ian:
You got it right. It was fun to watch the video and recall all the “issues” with the M60 – closing the hatch cover with the bolt forward when in basic training – that cost me an hour of low-crawling in the mud. How easily the trigger assembly came off – I actually liked that for maintenance. Many burns on my hands and arms when changing barrels or moving the bipod. And of course the “spray and pray” aspects of shooting it. I never used it combat but always had a smile on my face after taking it to the range.
I thought that the M60 was such a close copy/reverse engineer that they included features for alternative gas setting for semi-auto fire even though it was unnecessary – sounds more like a direct copy of FG42 >?
Red
Nope, the M60 wasn’t that closely copied from anything else, and it doesn’t have a manually adjustable gas system at all.
And a semi setting is definitely not necessary with this gun and would only serve to add parts. The rate of fire is slow enough that even with very little trigger time one can lear to pull singles and doubles pretty easily.
I bought a RIA model M60E3, that came with the original parts, E1, I guess is the configuration name, after shooting the Hollywood E3, I quickly realized, I really preferred the Viet Nam era set up. I just carry the safety glove in my kit box, and change the hot barrel after every belt of 100 rnds. It’s heavier, doesn’t bounce all over the place, and I’m able to hit targets much farther away. Maybe we can get you to do a follow up video, firing the Pig, in it’s original design configuration?
BTW, Chuck gave me a lot of Hell, over my choice, or lack of choice, in a Settlement of a 2 yr long divorce, of having to sell off my Beloved MG-42, to pay off my Ex-Wife, and keep my M60 instead! I rather would have kept the MG-42, but I didn’t have $35.000 sitting around, that she didn’t already abscond with!!!
We’re in the process of building a second gun that will be set up in E1 configuration and I’m really looking forward to shooting it.
I’ve had only a brief bit of time an the E1 that belongs to another dealer friend (it was actually my introduction to the 60 – needless to say I was immediately hooked, LOL). I’m very curious to shoot the two side by side to compare.
Other than a painful scorch/blister once because I stupidly put my hand on top of the hot barrel for leverage to retract the bolt for a newbie shooter (D’oh!), I can’t really come up with any negatives on the E3. We’ll see if that changes once I have some time with the E1.
FWIW: The M60E1 was never put into production and issued. You can’t mistake it for any other M60 variant, because the gas cylinder isn’t attached to the barrel, nor is the bipod.
The M60′s latter-day issues had more to do with slow repair policies in peacetime, and the change in lubricants from LSA to BreakFree. I speculate that the lubrication change was the biggest cause of wear, as my need to stone all the peened surfaces went up exponentially after that. Towards the end of its service, I started telling armorers in my units to start using the LSA they now had on hand again (for the MK19, which requires it…), and the wear issues went down. Shortly after that, they finally did the M240 thing.
As to the “old, worn out weapons” thing causing the problems? Nope. I took a brand-new, fresh from the factory (not rebuilt at depot) SACO-Maremont M60 out of the wrap at my second assignment in Germany, circa 1985. A month later, we went to the field at Hohenfels for a 30 day FTX that included battalion-level qualification ranges. As it turned out, due to massive idiocy in the other companies of the battalion, my company had the only 3 operational M60 MGs in the battalion, which were then used to qualify the entire battalion. In the course of three days, my brand-new M60 fired well over 15,000 rounds. At no time was it abused, nor was the rate of fire exceeded. The range cadre was careful as hell with those guns, knowing that those were the only weapons they had to get the battalion qualified. When we returned to home station, all three of those weapons went to third shop for wear, and were coded out. The receiver rivets were so loose in mine that the damn thing rattled when you shook it after disassembly. After that, I lost a lot of faith in the weapon’s durability.
As to the positive memories of the Vietnam-era veteran? You have to remember that a lot of these guys didn’t carry the same gun for their tours in Vietnam. A high-tempo unit like the 173rd might turn in weapons for refit every few months or even weeks. I asked one of the guys who was there about this issue, and he said he didn’t think much of it at the time, but he’d gone through three or four guns himself during the period he was an M60 gunner, about six months. If you read Stan Goff’s “Bloods”, a memoir of a young black Soldier, you’ll find a scene where he describes firing his M60 in a firefight to the point where it essentially came apart on him. These events happened with great regularity, from what I’ve been told by veterans of the war. The key difference, I believe, between the Vietnam era and the late part of the M60′s tenure was that the guns were constantly getting replaced and rebuilt during the Vietnam era, which was not happening in the latter days of peacetime. You do not want to know how much trouble it was to try and convince the people over at the Department of Logistics that a gun was worn past the point of use. Budgets were tight, and they put crap back into service that they knew wasn’t serviceable. At the time, the lie was that we’d get all new from war stock when the time came to deploy. I had the misfortune of finding out how much of a lie that was in 2003, when we left with a bunch of worn-out, clapped out crap that shouldn’t have passed inspection. By then, thank God, the M60s were gone.
Kirk, that’s interesting about the rattling rivets after only 15k rounds. I’ll have to check with my partner to see how many we have through this gun, but I’d be willing to bet it’s somewhere in the 10 or 12k range at present and no noticeable issues yet (knock wood!).
A lot is going to depend on which variant of receiver you have on yours. The later versions were spot-welded and had heavier rivets in places the Vietnam-era guns didn’t. The SACO-Maremont I pulled out of wrap had a late 1960s production date stamped on the VBL, so it was a good examplar of what the gun would have been like during the Vietnam era.
I think a large part of the problem was the lubricant. When I ran my arms room as a private, we were still transitioning from LSA and RBC to BreakFree, and it was only after we quit using LSA that the wear and peening went up so much. I didn’t make the connection until we were sitting through the New Equipment Training on the MK19, and the instructor starts explaining the requirement to only use LSA when lubricating it. Right then, , a bell went off in my head, and I started wondering whether or not the same thing was going on with the M60. After I started getting the guys to use the LSA on the guns, wear rates and peening went down.
The M60 was the sole reason we had stones and files in the armorer’s tool kit, along with the aircraft safety-wire pliers and stainless-steel wire. The fact that these tools were necessary at that level sorta indicates to me that the design of the gun was seriously half-baked. The near-infinite number of ways you could mis-assemble the damn thing only served as more proof the designers should have been fired.
About the only truly impressive thing about the M60 are the barrels. I believe they may be the only mass produced MG barrel in a rifle caliber that had a Stellite liner, and it’s something that should be a point of pride: From what I’ve read and been told, both the UK and FN signally failed to accomplish this for the MAG58 or the L7. I hope the technology isn’t lost, because I loved the durability on those things. Granted, the FN barrels are good enough that I know people who build sniper rifles with the blanks, but… Stellite. That’s all I can say.
LSA is a heavier viscosity than CLP, right? So you’re saying that (in your experience) the heavier weight lubricant reduced some of the wear on the gun? Makes sense I suppose.
LSA is an oil-based persistent lubricant. CLP is a kerosene-based evaporative lubricant with Teflon suspended in it. Once the volatiles evaporate, there’s not much there past a thin layer of residual Teflon, as far as a lubricant goes. This is insufficient, in my opinion, for anything other than the M16. LSA provides a not-inconsiderable cushioning effect between its parts via it’s viscous oily property.
With BreakFree CLP, you’re essentially running the “engine” of the M60 dry, without oil. It is, in my current opinion, about like running an old-school combustion motor on a too-light viscosity of motor oil, and gets you similar results. I would not recommend CLP-class lubricants for machine guns, at all, unless they were designed for them.
There’s a discernible difference in wear when you make the switch. I couldn’t figure out why all the old timers were looking at me like I was crazy when I complained about the hours of inspection and stoning on the M60s in the arms rooms I ran, because they’d never seen it when they were running the guns on LSA. I’m still not certain we did ourselves any favors by going to CLP.
The thing to remember about LSA is that it was originally developed for the M61 Vulcan. Any lubricant more viscous was thrown off the mechanism when it spun up to 6,000rpm. Nobody really thought it would be suitable for infantry small arms until the XM16E1 started to choke, and there was a mad rush to find some sort of lube that would keep it running better than the issue PLS (VV-L-800A).
Great video, as usual. The comments, especially Kirk’s, are very informative. I’m so old that I never used or trained on an M60, only M1919s, both ground and tank coaxial versions. They ran like sewing machines as long as they were headspaced and lubed properly.
terrible gun, terrible design, terrible manufacture. We could have had the MAG way back but NIH ruled the roost with Ordnance back then more than ever. Bad enough that Armor couldn’t be fooled and adopted the M240C long before the Infantry managed it, worse o the machinations the USMC went through to achieve the same ends.
Perhaps we can put that part of history behind us now.
Actually, I think the manufacture was a triumph of American ingenuity, as evidenced by the barrels. The design sucked massively, though–I can’t argue that one bit.
Adoption of the weapon wasn’t something done by the branches, either–Ordnance had just as much to do with the M240 adoption as Armor did, and if you track the lineage from the M1919 up through the M73 and M219, you’ll see they’d tried and failed until forced to pick the winner from a competition that is notable mostly because one of the controls, the PKT, was the actual far-and-away winner. Despite the fact that the tested weapons were battlefield pick-ups, and the ammo fired through them wasn’t exactly pristine.
The M240 should never have been adopted, either: Proper testing and fielding would have revealed that it was too damn heavy for its intended role as a light support weapon in the ground role, and that would have meant picking something else. The problem was that the Infantry branch did not trust Ordnance to actually do a real fielding/test regime, and the Marines were equally impatient. So, we got a weapon that really didn’t meet the needs for how we intended to employ it, and are now stuck trying to come up with weight-saving measures that should have been taken into account during the adoption for this role.
Basically, what I’m saying is that while the M240 is a superior weapon to the M60, it’s also not quite what we needed. The failure of the small arms procurement branch in the US military is quite clear, from what happened, and is continuing to happen. Witness the utter lack of development of new munitions for the 40mm, while we go full speed ahead on the XM-25. I figure it will be a couple of years, but that thing has “SPIW” and “OICW” written all over it. Billions wasted that could have gone to upgrading systems that actually, y’know, work…
One little known story concerning the M240 MG’s adoption is that FN also produces jet engines. They would be the prime contractor for the engine for whichever fighter NATO selected to replace the F-104 Starfighter. I’ve seen US State Department telegrams which mentioned that the French government promised to adopt the FN CAL if FN would give the nod to the Dassault Mirage F1′s engine. In turn, FN officials suggested to US officials that they’d look favorably on the F-16′s engine if the US would consider the MAG58. Of course, the French wouldn’t have adopted the CAL under any circumstances, nor would FN have been guilable enough to believe it. The important thing was that the US officials would believe that it was a viable threat.
You have to remember that before the M240C was put in the tanks we had the M73/M219 monstrosities which made the M60 look as reliable and durable as an M2HB. The story was, may or may not be true, that when we emergency shipped M60 tanks to the Israeli army in ’73, they threw the M73′s away because they were so bad. Even if they didn’t have a M1919 to plug in the co-ax hole. No gun was better than one of those pigs. The M240 was a dream and I loved using it.
Ding ding ding! Yep, now there is a gun (M73/219) for a new website: “wish I could forget weapons.” Ingenious concept, but they probably should have confirmed it worked before designing tanks around it. The old engineering error, “scheduling an invention,” maybe. Or the old all-purpose error: “wishful thinking.”
I’ve been meaning for a while to do a writeup based on some period technical articles on the adoption of the M240. As most of you guys know, it beat out a product-improved 219 and a tank-version of the M60 (even more dreadful than the infantry version) in a series of tests. That there were dope deals happening between countries, as Dan Watters suggests, I don’t doubt, but the MAG was a better gun 54 years ago and it’s still a better gun.
There are some deficiencies in the 240 vis-a-vis the original mag, mostly where Army Ordnance micromanaged the specs and forced FN to substitute inferior design, materials and finishes. For example, Belgian MAGs and Minimis are all satin chromed internally and are a joy to clean. The US 240 persists in the retarded M60 “feature” of requiring the bolt to be back to close the feed tray cover. The Belgian MAG has a clever springloaded follower cam which i another way to let the cover close with the bolt forward, like the MG42.
Kirk is right about the Stellite liners — hell of a job of manufacturing and matallurgy. You can still shoot one out but it takes some doing. They are in some .50 barrels but I don’t know which ones. Mostly associated with large caliber guns, extremely expensive and difficult alloy to work.
Another positive feature is ergonomics. But on reliability grounds, they were better off with the 1919.
One flaw is the provision of adjustable sights on the fixed part of the gun, with a barrel that is changed and changes the point of impact. The barrel can only be conveniently changed on a hot gun if it’s on the tripod. (And if it’s not a hot gun, there’s no urgency to changing the barrel).
One M60 weakness well known to operators is the tendency of (some?) receivers to stretch. This is a real problem for civilian operators given ATF’s ruling on replacing a damaged a receiver (shorter ATF: two words, and the second word is “you!”).
Some of the 60′s bad reputation is due to wear-out, some certainly due to bad design and too-gentle testing, and some of it from my era is that many 70s and 80s soldiers shot them mostly with blanks, and the gun doesn’t really work well with blanks. Some of that is the cheesy blank adapter, which was born dead in a tin can factory. We had all kinds of problems with them even with ball and tracer, but they were useless with blanks. Of course, until the mid-Reagan-first-term years we didn’t have any blanks, so the problem was masked by relative poverty for a while.
I always thought it amusing that the geniuses at Ord copied the MG42 feed tray cover wrong, and copied the FG42 bolt and op rod apparently without realizing they were copying the Lewis Gun second hand. A look at the reliability and maintenance history of the Lewis might have dissuaded them.
Great vid and comments. Thanks.
I’m curious, was it the bolt, the trunion or both surfaces which peened?
I was going to have an early night, I’m off to read up on the Lewis Gun instead.
Typically, the bolt lugs were the primary issues, along with the tower from the op rod up to the bolt. You’d also see peening on the op rod itself, where the sear notches were.
The biggest problem with the weapon is that the original designers did not understand a lot of the little details that the Germans incorporated into the MG42 and the FG42, and did not incorporate them into the design. One area where they failed to do this was the op rod/sear interface and trigger: The Germans had what amounted to a spring-loaded secondary sear, that prevented a lot of the problems the M60 experienced due to unfamiliar operators. On a machine gun like the M60, trigger control is much different than on a rifle; there is no room for “gentle squeezing until the sear releases”. Doing so allows the sear to not-quite-engage the sear notch as the rod reciprocates back and forth, vastly increasing wear. The M60 gunner has to be broken of his rifle-based trigger control, and taught to use a pull that feels very much like what we harp against in rifle training–Jerking it. Quick clean pulls, and equally quick releases are required. The MG42′s spring-loaded secondary sear prevents a lot of this problem, and vastly reduces wear to the sear and sear notch. Of course, the designers of the M60 did not pick up on this, and “simplified” the design. There are a couple of other areas where they did the same thing, to the detriment of the weapon.
Designing a weapon by copying or reverse-engineering is not as simple as it looks. You either have to do a deep study of why the original designers and users did things that way, or you need to slavishly copy every little detail, even without understanding why they did things that way. Anything else leads to things like the M60, where they ignored the need to have a feed tray cover that could be closed with the bolt forward, and a whole host of other issues.
Thanks Kirk.
Can I bounce a wild a$$ed guess off you?
I’m sure that lubricant has a lot to do with this, a lubricant film provides a great way to spread a shock load over the whole bearing surface (hence why plain hydrodynamic bearings are used whenever possible for big and small end bearings in IC engines, where they last for thousands of hours, and engines which use rolling element bearings need them changing every couple hundred hours).
I’m wondering whether manufacturing method also has a role to play in this.
German practice and early 20th century practice in the US was to deeply case harden parts like bolts and receiver locking members, giving a skin which was both intensly hard, and which had locked in compressive stresses, simillar to those which cold working and shot peening aim to produce.
From the mid 20th century, common US practice has been to machine the part from a through hardening medium carbon steel such as 4140/4150 or the nickel bearing equivalent 43 series steel.
This gives a part well able to withstand the overall stresses imposed on lugs, bolt face etc, but surface hardness ranges from the high 20s to around 40 Rc, and as Al Haral’s (rather coarsely gridded) stress modelling shows, lug stresses are not evenly distributed across the bearing surfaces http://www.varmintal.com/abolt.htm
Surface hardness of the carburized (or carbo nitrided if cyanide is used) part is more like Rc 60.
One place I worked, we shared office accommodation with guys designing the hydraulic hammers for rock drills. Those things hammered so fast that they screamed, and were expected to work 8 hours a day. Impact faces were case hardened for strength and for the additional fatigue resistance that the compressive stresses in the skin gave.
Do you (or anyone else) know whether the bolts and trunions were case hardened?
certainly it sounds as though this is (at least) a two part problem, and with the old lube, bolt and trunion durability was almost acceptable.
Which bit of the receiver / trunion caries the serial number for the bureaucrats?
I’m not a mechanical engineer – just an interested amateur, so take this with due scepticism.
If the parts were not case hardened (from your description of scuffing and peening they don’t sound like they were) 41** and especially 43** steels are suitable for case hardening. slight volume increase accompanies that, which would allow for slight stoning to clean the surface.
A dip in acidified copper sulphate copper plates the whole part, including the roots of threads, protecting them from absorbing carbon (a dip in ammonia solution strips the copper off again) polishing the copper off the requires surfaces exposes them to absorb carbon.
After carburizing to give the required depth of case, the part is given a two stage heat treatment, first stage to refine the grain of the core and harden it, second phase to harden the case, while tempering the core.
Hard chroming would also allow parts to be selectively built up with a hard, low friction surface (a 24 hour bake after chroming, drives off the absorbed hydrogen)The locking surfaces of the VZ58 are hard chromed to reduce friction and wear.
Kieth, I really have no idea what they did at SACO-Maremont to heat treat these parts. What you’re suggesting rings true, however, because of the apparent softness of some of the parts.
Probably the worst point for peening was the tower from the op rod to the bolt, which locked into the cam path of the bolt and around the firing pin. The forward surface of that part was always the worst wear point, followed by the bolt lugs themselves, then the sear notches. Some parts were noticeably harder to stone/file smooth again, namely the bolt lugs and sear notches. I always took the comparative softness of the tower (I forget the exact nomenclature, since nobody ever used it… Bolt cam lug?) as a sort of five penny fuse protecting other parts by taking the wear they’d take otherwise. Or, so I hoped the rationale went, at echelons higher than mine.
“One area where they failed to do this was the op rod/sear interface and trigger: The Germans had what amounted to a spring-loaded secondary sear, that prevented a lot of the problems the M60 experienced due to unfamiliar operators. On a machine gun like the M60, trigger control is much different than on a rifle; there is no room for “gentle squeezing until the sear releases”. Doing so allows the sear to not-quite-engage the sear notch as the rod reciprocates back and forth, vastly increasing wear. The M60 gunner has to be broken of his rifle-based trigger control, and taught to use a pull that feels very much like what we harp against in rifle training–Jerking it. Quick clean pulls, and equally quick releases are required.”
Indeed. I noticed this in ROTC in 1976. I’ve often said it was the ONLY firearm I’ve ever used where you HAD to jerk the trigger. When I was on active duty from 1980 to 1984, all we had were thrashed M60s and I simply hated them.
If I knew his name, I’d curse the despicable wretch who botched the drawings for the reversed engineered MG42. How on EARTH could somebody assigned to such a project NOT know the difference in length between .30-06 and 7.92x57mm Mauser?
If the Engineers at Springfield Armory, would have measured the conversions of the Prototype MG-42, to our 30-06, we most likely, would have been using the MG-42, US made, first in 30-06, and later in 7.62 NATO?!?!
Think about that one!
Actually, probably not. If you read through the reports of the various American agencies and departments that evaluated the MG42, you’ll find a common thread: They did not understand it, nor did they agree with the concept it personified. For the Germans, the MG42 was the crew-served center of the squad, providing the majority of the firepower; tactics were based on the idea of getting the MG and mortar into position and supporting them. Individual soldiers existed to carry ammo and provide security.
The US concept of tactics was the antithesis of this: The individual weapon trumped all, with the mass of firepower potential diffused across the squad, and the individual weapon was meant to provide the majority of the firepower to fire and movement techniques. Crew-served weapons were platoon-level assets meant to provide supporting fires only.
Ironically, the two concepts were virtually merged on the ground, de facto, when the Germans went to the StG-armed formations, and the US started sticking belt-fed MGs into the squad structure.
Be that as it may, the bureaucracy that provided weapons to the US Soldier never understood, nor supported the sort of concept of combat that the MG42 exemplified. The odds that they’d have adopted the damn thing even if they’d managed to properly copy it were slim and none. The reports documenting their studies of the weapon are festooned with references to it having too high a rate of fire, and a myriad of other “flaws” that actually represent German requirements for their tactics. In all likelihood, the US MG42 was a non-starter regardless of what had happened when they tried copying it.
The folks at GM-Saginaw Steering Gear were tasked with too much when they tackled the T24. They were trying to simulataneously convert the MG42 to .30-06 -and- cut the cyclic rate to nearly half. It should have been a parallel development. One team should have been working on a straight .30-06 conversion for the MG42 without regard to the cyclic rate. The other team should have been trying to slow down the cyclic rate of the MG42 in its original 7.92x57mm chambering.
Kirk,
How much of US military tactics do you think is based around the BAR having been the Squad Automatic, and its characteristic low rate of fire?
I think it’s actually the reverse: The slow rate of fire is due to the tactics. US belief was that slow, aimed semi-automatic fire was superior to fire mass and volume. This is why we equipped our infantry with an advanced semi-auto individual weapon, a mediocre SAW, and primitive or no belt-fed weapons at the squad level in WWII.
The US literature talks a lot about such brilliant ideas as “marching fire”, while the Germans were of the opinion that the MG enabled maneuver, the point of which was to get your MG into a better position to fire at the enemy. When you look at it, the US Army is the one who should have developed the assault rifle concept, not the Germans. As it was, the two schools more-or-less converged by the end of the war, when the Volksarmee formations that had the Stg-44 essentially mimicked the US platoon structure, where the platoons held the belt-feds and the squads consisted of riflemen who maneuvered.
Thanks
Thanks for the video. Always great posts here. Though I don’t get to work on M60s as much any more, they still come across my table once or twice a times a year. Plenty still in storage (with tons of parts) and a few still in use. Just not many.
[...] associated with them – Compare and contrast the two twits in the video above with the guy in this one. Which would you rather share beer and conversation [...]
The best English language record of the employment of the MG.34 and MG.42 by the Wehrmacht in WW II is Gunther Koschorrek’s “Blood Red Snow: the Memoir of a German Soldier on the Eastern Front”. Although it is a general memoir of combat, Koschorrek was a heavy machine gunner and gives considerable insight into the tactics and idiosyncracies of these weapons.
The M60 bolt and piston is 8620 steel casehardened to 0.012″ to0.015″. I think that this casehardening should have been at least 0.020″ but the problem is Earl Harvey ( the designer) should have employed a sliding fricion expert to get the correct slope to the unlocking cam. APG reports post war found that the second model FG42 would only last about 5k rounds until there was major parts breakage.
As to post war adoption of the MG42 the British were keen but it was politically impossable.
The post war MG3 guns solved the bolt forward/close cover problem by having a sprung post that re-corrects when the gun is cocked, also the MG42 trigger/sear mechinism does not allow the safety to be applied when the bolt is closed.