338 Edge go no go.

[Buster95]

I found a used stainless Savage 116 large shank in 300 RUM, I ordered a McGowen stainless Savage pre fit 30" bull barrel, to check the headspace do I need 338 Edge go no go gauges or 300 ultra mag are good too?

 

[orwapitihunter]

300 Ultra is the same.