Originally Posted by fireblade
The t-bar filler if found on a mk1 will most definitely be a retro fit, by the owner or by AA if it was serviced by them after the mk2 had been released and mk1 discontinued.
The mk1 barrel ( lothar ) had the brass transfer port because walther at that time could not produce the barrel with a transfer port built in and guarantee its quality/accuracy,
Agreed, a T-bar filler would be a later upgrade. But what I meant was that very early ones came with this type of filler (factory fit, was in the manual)....
Which then changed to this type in later Mk1s...
And the Mk2 onwards had the T-bar type....
Also, I thought Mk1s had a CZ barrel as Holly said, which have a flat machined into them, hidden under the muzzle brake.