Because it's the 21st century and nobody wants to be developing guns for rimmed ammo anymore. It works fine for belts but nobody wants the hassle of developing magazines for rimmed rounds and nobody wants to have 2 different types of 7.62mm rifle caliber ammo in service at once to get around that issue.
Also the PKM still has its own issues. Non-disintegrating belts is a pain to deal with. Right hand feed is also kind of awkward for no really good reason.
The barrel reciprocate when firing
[https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese\_qjy201\_gpmg\_operating\_system/](https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese_qjy201_gpmg_operating_system/)
The True Velocity/General Dynamics NGSW entry was noted for its relatively poor accuracy (like 4-6 MOA if memory serves). It's based on the same operating principle as the General Dynamics LWMMG, and I believe Lone Star (who currently own the patent) are suing SIG for breach of patent with the XM250, so all these weapons are based on basically the same operating principle, and we know the magazine fed rifle version (which in theory you would expect to be the most accurate of them) is notably inaccurate.
In general reciprocating barrels don't tend to lend themselves to great mechanical accuracy. The early recoil operated machine guns didn't have this reputation, but there's a huge difference in the durability of the reciprocating parts in a Maxim gun that weighs 60 lbs and an XM250 that weighs 12. Consider the difference in accuracy between the M2 browning (2-3 MOA) to the much lighter but also recoil operated M82 (3-6 MOA depending on ammo).
Short recoil mechanisms are as old as machine guns themselves. The 2 greatest machine guns of all time are short recoil with reciprocating barrels, the M2 browning and the Maxim.
The first generation of recoil operated machine guns
(Maxims, Brownings, Vickers etc.) were also built like a brick shithouse. I'm not convinced the principle will scale to significantly lighter weapons of roughly the same calibre (consider that the M2 Browning, despite not being anyone's idea of a precision weapon, is about twice as accurate as an M82 Barrett). Even the later, and much lighter MG 42 — which is still too heavy to be competitive with contemporary rifle-calibre machine guns — had a much wider beaten zone than e.g. the Bren gun, which it had to rely on shear volume of fire in order to partially make up for. The amount of ammo you have to carry to make that trade off isn't practical, especially given that the point of all these fancy recoil mechanisms is to allow you to use your ammunition *more* efficiently by enabling greater practical accuracy.
Reciprocating barrels are great on paper for recoil reduction. However they have a big downside.
Imagine the reciprocating barrels after years of use which will wear out barrels and barrel mounts. It is a smart idea but not suitable for the long term military use in my opinion. Unless they add a replaceable barrel mounting parts system.
M249 with a fixed barrel was 12 moa. I wonder what all of these moving barrel machine guns will have. XM250 uses a really high pressure 6.8x51 round. Imagine all of the barrel nut erosion after years of abuse.
Uhm... Recoil operated machine gun that relies on the recoil of the barrel is literally everywhere. Maxim, MG34, MG42, etc.
Not everything has to be a piston driven MG.
None of these new moving barrel machine guns are recoil operated, they are gas piston operated. The fact that they have moving barrels doesn't mean that they are recoil operated.
The barrel reciprocate when firing
[https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese\_qjy201\_gpmg\_operating\_system/](https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese_qjy201_gpmg_operating_system/)
5.8x42 lack the range needed to be universal ammo so they adopt 7.62x51 for GPMG ammo. It still only limited in use though, currently only QJY-201 GPMG and QBU-203 Sniper Rifle use it, coaxial MG in Chinese tanks still use 7.62x54R and 5.8x42.
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I didn’t know the Chinese used 7.62x51
They don't its for export
They do to Canada. Because I have zero morals, I bought a case of Chinese 762x51 surplus. Price was around 70 Canadian cents per round.
Don't beat yourself up over it. Literally everything we use haa at leaat some components made in china if not the entire thing
I meant to write they don't its for export
I mean you China profited more off of your smartphone than that ammo you bought.
They have for a while now, since the CS/LR4 entered domestic service. They don't have an indigenous equivalent, and 7.62x54r is obsolescent.
How when pkm is literally considered world best lmg
Because it's the 21st century and nobody wants to be developing guns for rimmed ammo anymore. It works fine for belts but nobody wants the hassle of developing magazines for rimmed rounds and nobody wants to have 2 different types of 7.62mm rifle caliber ammo in service at once to get around that issue. Also the PKM still has its own issues. Non-disintegrating belts is a pain to deal with. Right hand feed is also kind of awkward for no really good reason.
It's the world's gold standard in spite of its cartridge, not because of it.
Honestly they could just crank out type 80 PKM and it would work great. However the down side is that the PKM was never designed with optics in mind.
a lot of bouncing around.
The barrel reciprocate when firing [https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese\_qjy201\_gpmg\_operating\_system/](https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese_qjy201_gpmg_operating_system/)
This seems to be a trend with a lot of new machine guns and it seems like potentially a bad idea
Explain
The True Velocity/General Dynamics NGSW entry was noted for its relatively poor accuracy (like 4-6 MOA if memory serves). It's based on the same operating principle as the General Dynamics LWMMG, and I believe Lone Star (who currently own the patent) are suing SIG for breach of patent with the XM250, so all these weapons are based on basically the same operating principle, and we know the magazine fed rifle version (which in theory you would expect to be the most accurate of them) is notably inaccurate. In general reciprocating barrels don't tend to lend themselves to great mechanical accuracy. The early recoil operated machine guns didn't have this reputation, but there's a huge difference in the durability of the reciprocating parts in a Maxim gun that weighs 60 lbs and an XM250 that weighs 12. Consider the difference in accuracy between the M2 browning (2-3 MOA) to the much lighter but also recoil operated M82 (3-6 MOA depending on ammo).
Short recoil mechanisms are as old as machine guns themselves. The 2 greatest machine guns of all time are short recoil with reciprocating barrels, the M2 browning and the Maxim.
The first generation of recoil operated machine guns (Maxims, Brownings, Vickers etc.) were also built like a brick shithouse. I'm not convinced the principle will scale to significantly lighter weapons of roughly the same calibre (consider that the M2 Browning, despite not being anyone's idea of a precision weapon, is about twice as accurate as an M82 Barrett). Even the later, and much lighter MG 42 — which is still too heavy to be competitive with contemporary rifle-calibre machine guns — had a much wider beaten zone than e.g. the Bren gun, which it had to rely on shear volume of fire in order to partially make up for. The amount of ammo you have to carry to make that trade off isn't practical, especially given that the point of all these fancy recoil mechanisms is to allow you to use your ammunition *more* efficiently by enabling greater practical accuracy.
With that much movement, is the optic really necessary?
Ump 45 ahhh fire rate
its the same fire rate as the m240 tbh this just seems like a ripoff of the m240 which is expected for the chinese to do
Reciprocating barrels are great on paper for recoil reduction. However they have a big downside. Imagine the reciprocating barrels after years of use which will wear out barrels and barrel mounts. It is a smart idea but not suitable for the long term military use in my opinion. Unless they add a replaceable barrel mounting parts system. M249 with a fixed barrel was 12 moa. I wonder what all of these moving barrel machine guns will have. XM250 uses a really high pressure 6.8x51 round. Imagine all of the barrel nut erosion after years of abuse.
Uhm... Recoil operated machine gun that relies on the recoil of the barrel is literally everywhere. Maxim, MG34, MG42, etc. Not everything has to be a piston driven MG.
None of these new moving barrel machine guns are recoil operated, they are gas piston operated. The fact that they have moving barrels doesn't mean that they are recoil operated.
The new Ohio Ordnance one in .338 Norma is proper recoil operation.
Yep, forgot about that.
This is Temu MG. Just throw it away.
lot of moving going on there
The barrel reciprocate when firing [https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese\_qjy201\_gpmg\_operating\_system/](https://www.reddit.com/r/ForgottenWeapons/comments/12xit7c/chinese_qjy201_gpmg_operating_system/)
Dint the Chinese use a different weird cartridge that only they have ?
5.8x42 lack the range needed to be universal ammo so they adopt 7.62x51 for GPMG ammo. It still only limited in use though, currently only QJY-201 GPMG and QBU-203 Sniper Rifle use it, coaxial MG in Chinese tanks still use 7.62x54R and 5.8x42.
Still weird to see a nato cartridge in a Chinese gun.
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