Home made headspace gauges

[CentrePunch]

Hi guys,
i enjoy making my own tools and gauging for rifle building projects and i want to make a pair of 6mmBR go and no-go headspace gauges.
However i cant find any info of the base to headspace datum ring dimension, can anybody help?
Many thanks.

Ian.

 

[kendog]

This should help. Shows min and max. No-go is typically .004" over min.

 

[CentrePunch]

Thanks for that kendog, I notice the drawing is for 6mmBR Rem would this be the same for the now standardised 6mmBR Norma?

Ian.

 

[kendog]

Yes.

 

[CentrePunch]

Once again thanks for putting up a print kendog but as you are aware, dimesionally 6mmBR Rem and 6mmBR Norma have slight differences, yet strangely apart form the length of the lead, throat and throat angle the prints are identical ???

Ian.

 

[kendog]

The headspace dimension its typical for all the Rem BR chambers, per the JGS drawings. Not sure if SAAMI has standardized this chamber or not. It isnt on their website. I just rebarreled a 22 BR to 6 Norma. The 22 was a tad long by the gauge reading, but the owner shot it that way for years with no ill effects and had great accuracy until the throat shot out. He sized his brass accordingly and had no problems. I set the 6 barrel to minimum and it started right out of the gate with little bughole groups.

 

[MDSpencer]

Are you going to Heat treat and grind your gage or gages?

 

[CentrePunch]

Yes i am going to make them out of silver steel (dont know what spec that is in the US) harden them and then finnish them with the toolpost grinder.

Ian.