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Military Guns and Ammunition

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This is intended for people interested in the subject of military guns and their ammunition, with emphasis on automatic weapons.

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NGSW Phase 2 Consolidation and info   Small Arms <20mm

Started 30/8/19 by gatnerd; 192422 views.
poliorcetes

From: poliorcetes

5-Jul

I am not 100% sure about HK changes and refinements of LSAT design. 

https://twitter.com/xmszeon/status/1411617914860494850

xmszeon thinks that now rising chamber works more modularly and in a simplified way compared with the system deduced from patents

https://twitter.com/xmszeon/status/1194136894654894083

Now there is not a vertical guide but a groove inside the sliding chamber, and in the stupid video it seems that the chamber when rises is going to be placed in a sort of "sealing chamber for the chamber" or whatever

DAMN I'M NOT PRONE TO HATE ANYBODY, BUT WHEN I REVIEWED ONCE AGAIN THE VIDEO I DID HATE WHEN I SAW THEIR FACES AND NOT THE PUTAS PARTS!!!

Frustration vented, back to normal

stancrist

From: stancrist

5-Jul

nincomp said:

I wonder if it is comment about the properties of the polymer?

It could also be a backhanded comment about possible issues with the True Velocity case.

"The chamber...is not attached to the barrel.  This is not a smart idea to stick all-polymer ammunition in a hot barrel."

He said nothing about properties or types of polymer, so it does not seem to me that's what his comment was about.

It very well could be a shot at the True Velocity ammo, which does sit in a chamber that's an integral part of the barrel.

stancrist

From: stancrist

5-Jul

poliorcetes said:

DAMN I'M NOT PRONE TO HATE ANYBODY, BUT WHEN I REVIEWED ONCE AGAIN THE VIDEO I DID HATE WHEN I SAW THEIR FACES AND NOT THE PUTAS PARTS!!!

Frustration vented, back to normal

???  The parts were shown, and quite clearly.

----  Lower receiver     https://youtu.be/pYqEJsMLg_g?t=492

----  Ejector Module     https://youtu.be/pYqEJsMLg_g?t=523

----  Buffer Assembly   https://youtu.be/pYqEJsMLg_g?t=549

----  Firing Pin Carrier  https://youtu.be/pYqEJsMLg_g?t=569

----  Chamber                https://youtu.be/pYqEJsMLg_g?t=574

The same format was used for the Textron NGSW-AR video.  https://youtu.be/NRuycForGhA?t=253

All of the videography was done during one range session, then portions of the videotape used to make three separate videos.  The first was posted to YouTube in late 2020.  Next Generation Squad Weapons l 6.8mm Weapons & Ammo for Army NGSW l EXCLUSIVE With Textron Systems - YouTube

nincomp

From: nincomp

5-Jul

Would someone please explain to me the method used to seal the moving chamber to the barrel?  Sorry if this has already been done.

gatnerd

From: gatnerd

6-Jul

As far as I know no explanation has been given for how the chamber seals.

Perhaps it employs a similar 'gas seal' to that used in the Nagant revolver?

The M1895 by contrast, has a mechanism which, as the hammer is cocked, first turns the cylinder and then moves it forward, closing the gap between the cylinder and the barrel. The cartridge, also unique, plays an important part in sealing the gun to prevent the escape of propellant gases. The bullet is deeply seated, entirely within the cartridge case, and the case is slightly reduced in diameter at its mouth. The barrel features a short conical section at its rear; this accepts the mouth of the cartridge, completing the gas seal.

The Nagant ammo is even telescoped(ish) in its design:

But this is just a hunch on my part, I have no hard data to back up that guess. 

stancrist

From: stancrist

6-Jul

Your "Nagant theory" seems plausible.  It could be that the chamber is cammed forward against the barrel, after being cammed up in line with it.

Or perhaps the recoil spring pushes the firing pin carrier against the fully elevated chamber, which in turn is forced against the rear of the barrel?

autogun

From: autogun

6-Jul

gatnerd said:

The Nagant ammo is even telescoped(ish) in its design:

I wouldn't describe that as telescoped. The propellant is entirely behind the bullet, so the cartridge is as long as a conventional one, it just has an extended case. Telescoped ammo is shorter overall than conventional, as the projectile is (at least to some extent) buried within the propellant.

poliorcetes

From: poliorcetes

6-Jul

Come on, Stan, I saw what you saw

For instance, firing ping carrier: you have to pause the video in the exact frame and even then it is not possible to be sure about all the details. That is not the way you record a field disassembly.
 

Anyways, AR was slightly clearly recorded that this shitty piece. There even wasn't a static shot of the weapon field stripped!

It's more or less clear that, compared with the patent, HK has made a nice refinement work and now there are less pieces mounted in a more modular way. Indeed I would assume than this final design is as sound and resistant as SiG's and allegedly the decission is going to be focused on the advantages and trade-offs of CT cartridges 

poliorcetes

From: poliorcetes

6-Jul

My problem with that: if the chamber is cammed forward, how is the cartridge sealed at the back?

Conventionally, "forward seal" is straightforward: chamber and barrel are part of the same block all the time. "backward seal" is made by the bolt, tightly in contact with the chamber and with ridiculous tolerances

That is not possible with a sliding chamber

But since it is working, something interesting is happening inside...

poliorcetes

From: poliorcetes

6-Jul

The previous "s" guide for sliding the chamber is now a groove on the same chamber. Quite a nice refinement and a volume saving

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