6mmAR headspace

[wildchild]

So apparently the 6mmAR heads spaces longer than a 6.5 Grendel necked to 6mm like about .030?
Can someone confirm this?

 

[swehrman]

I checked the headspace on mine with a set of PTG 6.5 Grendel gauges and the bolt closed on the go gauge, and wouldn't close on the no-go gauge.

-- Scott

 

[wildchild]

Mmmmm
We'll comparing side by side the shoulder is taller by about .030 on the 6mmAR go gauge.
It was chambered and head spaced off the 6mmAR gauge but it's blowing my shoulder forward about .030 also.
Something it not right.

 

[swehrman]

Using the Hornady comparator I measure about 0.013" difference between brand new 6.5 Grendel brass, and fired 6AR brass from my chamber.

-- Scott

 

[wildchild]

Using the Hornady comparator I measure about 0.013" difference between brand new 6.5 Grendel brass, and fired 6AR brass from my chamber.

-- Scott

So your fire forming with false shoulder or hard jam?

 

[swehrman]

Neither, I just neck them down, load them up, and shoot them. 0.013" isn't enough of a difference to worry about IMO.

-- Scott

 

[jbarron]

What bolt are you using?
There is a difference in bolt face depth between a standard bolt and an improved bolt used for the Grendel.