Scar 17 barrel replacement

[The boogalorian]

I recently replaced the barrel on my scar 17. It is a factory barrel so everything bolted up without issue. You are supposed to be able to replace the barrel with little or no shift in the point of impact between barrels. I have not shot it yet.
I was playing around with it at my work bench tonight and decided to check the chamber with a "go" and a "no-go" gauges. The bolt closed on both the "go" and the "no-go" gauge. The chamber is a nato 7.62x51, and the gauges are for a .308.
Should I be concerned? Are the gauges not interchangeable for 308 and 7.65x51?

Thanks in advance for help.

 

[Dusty Stevens]

Put a piece of scotch tape on the back of the no go and see if itll close on that. If it does i wouldnt shoot it

 

[The boogalorian]

Thanks.

 

[Walt Krafft]

The military is not concerned about case life one bit. Chambers are generous and headspace can be greater than 308 before rejection. If I remember correctly, nogo is +0.006 and field is +0.010.