Here is another mehod to give a "close enough" measurement.

Size 5 cases to minimum, trim to minimum spec, load a moderate charge and shoot them in a clean chamber. Now compare case length before and after firing.

I know an old gunsmith who told me how to make a wax chamber cast. It takes time and effort, but is accurate enough to get the necessary specs.

You can make chamber casts from flowers of sulphur. Thanks what most smiths used in the olden days. It stinks to hell but I've seen casts made using it and they look excellent.

SAAMI chamber print can be found here

American National Standards Published by SAAMI

CIP chamber print can be found here

COMMISSION INTERNATIONALE PERMANENTE POUR L'EPREUVE DES ARMES A FEU PORTATIVES

All sorts of different .308 reamers can be found here

4D Reamer rentals

All you have to do is learn how to read a chamber print

Quote from: Ds J on May 12, 2024, 10:31 PMIf I use the GSC method I should be able to get a case sized to the actual specs of my chamber. Then, if I were to compare that to SAAMI specs, I should be able to calculate the difference in my own chamber.

A case sized - and or fired in your rifle chamber will always be slightly smaller than the actual chamber
It needs to spring back enough to be able to be extracted.
The ONLY real way to know what is going on in your rifle chamber is to cast it using cerrosafe or similar low melting point alloy





Making a chamber casting


Cerrosafe

Unfortunately no-one has been able to tell me where to get this in SA ?

Quote from: Shotofrank on May 12, 2024, 09:50 PMIts is so to say a way of finding out if you need to or not have measurements done professionally.

Purchase the right gauges and measuring instruments and learn how to use them
No need for "professionals"

If I use the GSC method I should be able to get a case sized to the actual specs of my chamber. Then, if I were to compare that to SAAMI specs, I should be able to calculate the difference in my own chamber.

The method described by GS Customs is in my opinion only for you to have a method of measuring without actually measuring.
 Its is so to say a way of finding out if you need to or not have measurements done professionally.

I am still using my 1990 Lee single stage entry level press. 1 to 100 rounds, no difference at all.

Surely there must be some form of recourse when woman do such malicious actions.