Headspace gage for 300 blk

[jjm408]

Anyone know where i can get a headspce gage for the 300 blk?

[Suputin221]

Brownells

[plant.one]

midway

[Dolomite_Supafly]

What kind of gun you checking the headspace on?

[jjm408]

I'm building a 300 blk ar. Rainier match barrel and rainier match bcg. Not sure i even need to check the headspace. Any thoughts??

[300Blk]

ARs have fixed headspace. A headspace gauge can identify an out of spec barrel or bolt. Is it needed? Only to the degree that the barrel or bolt may be defective. You can try asking them to check it before sending you the barrel and bolt.

[Pointnpull]

I'm building a 300 blk ar. Rainier match barrel and rainier match bcg. Not sure i even need to check the headspace. Any thoughts??

It's always nice to know for sure, but I'd say the chances are <0.00000001%, +/- 0.0000001, that the headspace won't be in spec with bolt and barrel coming from somebody like Rainier. I've got a Rainier Select barrel and AIM bolt/carrier, didn't check headspace before I fired the gun first time, but cases measured after firing had no signs of excessive or too little headspace. In fact, after full length resizing of once-fired brass (mix of Hornady and Remington), no trimming required to put the case within specs for length.

[jjm408]

Awesome, thanks for the replies.