Next generation rifles

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NRA Shooting

As previously detailed in these pages, the Army's Next Generation Squad Weapon (NGSW) efforts have resulted in multiple, unique 6.8 mm cartridge designs. Each of the companies involved has tried to develop a solution to the Army's reported desire to penetrate modern, peer-level body armor far beyond close-combat ranges. The selections of SIG Sauer's 6.8x51 mm hybrid-case ammunition, XM5 carbine and XM250 light machine gun as solutions have been met with both fanfare and skepticism. While the velocities that are reported for the 6.8x51 mm, and its .277 SIG Fury commercial counterpart, seem to generate the most excitement, this cartridge's projectile energy is likely to be the main driver of the DOD's interest.

According to SIG's published numbers, its hybrid steel-and-brass cartridge case allows chamber pressures to reach a whopping 80,000 psi. Subsequently, its 150-grain projectile is reported to leave a 16-inch barrel at 2,830 fps with 2,667 ft.-lbs. of muzzle energy. Running those numbers through a ballistic program shows that SIG's loads should fly flatter and hit much harder than anything used in current battle rifle and light machine gun designs, including 7.62 NATO/.308 Win. loads, out past 1,000 meters.

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s 150-grain projectile is reported to leave a 16-inch barrel at 2,830 fps with 2,667 ft.-lbs. of muzzle energy

that's gonna leave a mark!!!

can't believe the gun guys aren't all over this
of course at $4 a round in a 650 round per minute fully automatic rifle you're talking 100 to 120 dollars
a minute, even with robust fire discipline ...  that's some pretty rich shooting   

[CNCAppsJames]

... chamber pressures to reach a whopping 80,000 psi ...

YIKES!

[CNCAppsJames]

Pressures like that ... gonna throw a WAG out there and guess are going to require something along the lines of Waspalloy or Stellite sleeves well into the barrel to prevent the massive amount of throat erosion that would surely follow.

[Matthew Hajicek]

can't believe the gun guys aren't all over this

It's old news; they announced it months ago.

You can buy polymer cased ammo now:

https://www.tvammo.com/

significantly lighter, less chamber heat, and they claim higher performance as less of the energy is going into heating the chamber.

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It's old news; they announced it months ago.

You can buy polymer cased ammo now:

https://www.tvammo.com/

significantly lighter, less chamber heat, and they claim higher performance as less of the energy is going into heating the chamber.

This is something different

As previously detailed in these pages, the Army's Next Generation Squad Weapon (NGSW) efforts have resulted in multiple, unique 6.8 mm cartridge designs. Each of the companies involved has tried to develop a solution to the Army's reported desire to penetrate modern, peer-level body armor far beyond close-combat ranges.

they are using hybrid steel/brass cases to loaded to 80k psi chamber pressures in an effort to get very high velocities

According to SIG's published numbers, its hybrid steel-and-brass cartridge case allows chamber pressures to reach a whopping 80,000 psi. Subsequently, its 150-grain projectile is reported to leave a 16-inch barrel at 2,830 fps with 2,667 ft.-lbs. of muzzle energy. Running those numbers through a ballistic program shows that SIG's loads should fly flatter and hit much harder than anything used in current battle rifle and light machine gun designs, including 7.62 NATO/.308 Win. loads, out past 1,000 meters.

These would be some seriously expensive infantry weapons.
Meanwhile Russia is issuing WW2 vintage bolt action rifles to draftees with 3 days training and feeding them
into the meat grinder in Ukraine.   

[RobertELee]

at $4 a round in a 650 round per minute fully automatic rifle you're talking 100 to 120 dollars
a minute,

More like $2600/minute.

[mkd]

Fail
2700 fps while respectable, I wouldn't call that high velocity.
 The barrel burner; .22-250 designed in 1937 hits upwards of 4000fps  which as I vaguely understand it is near the top of the range for the propellant flame front. And they do it at 65ksi.

80ksi; barrel length would have a big muzzle velocity impact, eh?

[CNCAppsJames]

Regarding polymer ammo;
"True Velocity ammunition is not designed to be reloaded using commercially available reloading equipment. True Velocity does not recommend trying to reload their polymer cased ammunition cartridges in any circumstance."

[Jeff]

reported to leave a 16-inch barrel at 2,830 fps

PFFFT that's nothing!

"Do you realize the bullet out of an AR-15 travels five times as rapidly as a bullet shot out of any other gun... ?"   ~PedoJoe

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An article on True Velocity ammo