[SJSAMPLE]

Nope.
both use a gas-piston system.

It’s the bolt LOCKUP that’s different.
HK uses a roller bolt in the HK-9x series, while the HK-416 uses the standard rotating bolt lockup.

[Trailerpark Badass]

There is no gas piston the G3/HK91 series.

None of the propellant gas is used to power the operating system of those rifles.

And the 416's gas piston is nothing more than an updated AR180, so certainly not brand new.