02-02-2021, 02:23 AM
My understanding is that the headspace gauge represents an ideal round as opposed to being tied to any particular boltface counterbore depth.
It shouldn't matter whether one's bolt is a 6.5 Grendel/6mmARC Type 2 (I call mine Mk136) with a 0.136 depth or a 7.62x39 Type 1 0.125.
What matters is whether the chamber is reamed 0.011 deeper in a barrel headspaced to use a Type 1 bolt.
In either case, the headspace gauge used is the same.
But, yes, the cartridge was developed using the Mk136 or Type 2 bolt and it is the standard for the cartridge.
It shouldn't matter whether one's bolt is a 6.5 Grendel/6mmARC Type 2 (I call mine Mk136) with a 0.136 depth or a 7.62x39 Type 1 0.125.
What matters is whether the chamber is reamed 0.011 deeper in a barrel headspaced to use a Type 1 bolt.
In either case, the headspace gauge used is the same.
But, yes, the cartridge was developed using the Mk136 or Type 2 bolt and it is the standard for the cartridge.
:: 6mmARC Target Cartridge with Hunting Capability :: 6.5 GRENDEL Hunting Cartridge with Target Capability ::
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