Go or No-Go gauge or both?

[GlockViking]

My son has acquired a 91/30 from his uncle and wants to fire it, but I want to make sure it is safe first.

I was out at Midway and there is a Go and a No-Go headspace gauge and I don't know what I need! ACK!!

Do I need one (Go or the No-Go) or do I need both?

I am SO confused! ;f

Help!

[lead-lobber]

GLock Viking-
FWIW- If yer not going to be an avid collector of this caliber or type of rifle, Id hold off on the gauge purchase and take it to a gun smith and have them perform a saftey inspection on it. That may be the less than the amount for the gauge itself.

[BPD07]

Use a factory round for the Go gauge, You only need to buy a No Go gauge.