What tools are required if any and what is the process to remove a barrel from an action on an old turk mauser? Any advise would be great.
You need the following:
A barrel vise.
This is typically a press-like device using a hydraulic jack and very heavy "jaws, in which brass, aluminum, or even hard oak inserts are installed.
Here's an example of a typical vise setup:
Barrel vise inserts.
These are the inserts for the vise, and are typically split brass or aluminum "sleeves" that wrap around the barrel, or sometimes very hard, dense oak or plastic blocks that sandwich the barrel. When the vise is tightened, the insert compress around the barrel VERY tightly, gripping it so tightly, the barrel cannot turn in the vise.
An action wrench.
This is a special tool with a cut-out that is an EXACT fit over the receiver ring. The close fit supports and prevents the receiver from crushing, bending, or cracking when the receiver is unscrewed from the barrel.
These wrenches are made to fit a SPECIFIC type and size receiver, and even then often have to be shimmed with brass shim stock to fit better.
Here's a typical action wrench:
The barrel is degreased and dried, then locked tightly in the barrel vise. Care is taken to get the dry non-oily barrel locked as tightly as possible to prevent it from slipping and turning in the vise.
The action wrench, which has a handle, is used to break the receiver loose and unscrew it.
Sometimes you may have to put a section of pipe on the handle as a "cheater bar" or you may have to use a dead-blow hammer to help break the receiver loose.
On old military rifles, the barrels often have been in place for over 100 years, and are frozen in place.
There is a danger of damaging or ruining the receiver.
To install a new barrel requires more equipment, including (usually) a lathe, chamber cutters, and a set of head space gages.