Questions about the 6.5 "G" cartridge

[Sapper740]

I'm doing an article on the Japanese Type 11 light machine gun and have found a contradiction about the cartridge. Most sources say it used the 6.5 G "reduced charge" cartridge that produced lower pressures and velocities than the standard 6.5 Arisaka. But I just saw an episode of the NRA's "I Have this Old Gun" on TV and they claim the G cartridge was loaded with an improved powder but was otherwise identical ballistically to the standard cartridge.

Can anyone shed some light on this?

The 'G' cartridge was designed to reduce muzzle flash from the Type 11's 17 1/2" barrel with no reduction in velocity.