Comments by "ostiariusalpha" (@ostiariusalpha) on "Textron's NGSW 6.8mm Prototype M4 Replacement Deep Dive" video.

@ZURAD Well, Textron has already said that their 6.8mm cartridge runs at higher pressure, it's just not quite as high as the 90K PSI of the SIG ammo.
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@ZURAD Almost gets away with it, the Textron rifle does use a slightly longer barrel to reach the Army's muzzle velocity requirement, but much less length than the General Dynamics bullpup which operates at more conventional pressure.
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I'm fairly certain that AAI was using mostly Radel (polyphenylsulfone) in their original cartridges that operated at a conventional pressure. Their higher pressure 6.8mm NGSW round is probably also Radel, though perhaps with a PEEK/PEKK coating applied.
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