This is intended for people interested in the subject of military guns and their ammunition, with emphasis on automatic weapons.
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Pretty big news for TV and the advancement of polymer cases.
They have partnered with General Dynamics, a much larger defense contractor, and will be providing their cases for the .338 Machine Gun and NGSAR programs.
Looks like we're getting closer to a viable, lightweight case technology being fielded.
Found a nice video on Yotube of TV's presentation at SOFIC.
The two most interesting slides:
That seems to correlate to a 31% weight savings, assuming the rest of the pallet is identical. If its indeed a 31% weight savings that puts it within spitting distance of LSAT's 34% weight reduction, although LSAT has the edge when polymer MG links are factored in.
This is interesting because its the first real indication they've managed to actually get this working down to 5.56. It also shows a serious reduction in chamber heat, potentially allowing for a lighter barrel'd LMG / Automatic Rifle thats still sufficiently resistant to cookoff.
The video also confirmed that General Dynamics is indeed using TV's cases with their .338 LWMMG.
True Velocity is still plugging away.
Guns and Ammo has two good segments on them. The first covers a visit to the TV factory, and how tight the tolerances are on the cases (holding to 0.001" on the case wall; 0.0005" on the case mouth.) We also see confirmation that bullets are glued into the case mouth, which appears to be essential for these polymer cases vs brass/steel.
And an G&A article:
The more interesting video is the on on TV's Facebook, showing a different clip. This shows, for the first time I'm aware of, polymer 5.56 cases being fired. The shooter also describes a dramatic decrease in chamber heat due to the polymer cases (firing 100rd's FA and then being able to put a finger in the chamber right after without burning.)
Freshly ejected cases are cool enough to be stuck in the shooters mouth:
The important question: will it be cheaper than Wolf?
True Velocity is going to be partnering with Sierra and releasing their cases for commercial sale:
In fact, these cartridges are putting up numbers unsurpassed by brass-cased match-grade cartridges, as they're capable of sub-MOA accuracy at extended ranges and single-digit standard deviation in muzzle velocity.
I need their 5.56 ammo so I can pull the bullets and load M855A1 EPRs to put in my Kel-Tec RDB so I can fight robots while my built-in cybernetic mirrored shades are deployed.
Now on commercial sale in .308 Win (to start with): https://www.thefirearmblog.com/blog/2020/01/29/shot-2020-true-velocity-and-sierra-bullets/
Some more pictures of TV .308 Win here: https://forum.cartridgecollectors.org/t/308-win-from-sierra-true-velocity-composite-cartridge-case-new-for-2020/37308
A thought crossed my mind: as I understand it, one problem with polymer versions of metal cases is that the necks have to be very thin, hence TV preferring a neckless design for their clean-sheet 6.8 mm NGSW. A alternative approach might be to design a bullet with a reduced diameter at the case mouth, so the neck can be thicker. Not sure if this would allow enough contact with the bore to keep the bullet stable, though.
You certainly can do it that way, but there's really no reason to. The TV-NGSW neckless format has superior propellant capacity and compression characteristics.
As noted, a neckless design can allow a larger powder charge for a given length cartridge, or a longer projectile with the same charge. There have probably been designs that tried to tuck the neck backwards into a metallic cartridge body to get the same effect, but I have never seen one.
Years ago in one of the GPC threads here, I proposed the idea of using a neckless variation of the 7.62x51 to permit the use of a longer, higher-bc bullet. My thinking was that this would permit a reduction of propellant and recoil while still giving acceptable long-range performance. To be honest, I was pretty proud of myself for the idea.... for maybe 24 hours. The next day, Badcow (Emeric) posted that there was already a patent pending on the idea, but he couldn't discuss details. Sigh.
I am curious to see how much of the bullet's tail protrudes into the propellant space of the neckless designs. I have often read that doing so with a normal cartridge can reduce accuracy. Maybe this reduction is too small to be an issue for a military cartridge?