Hello,
I'm looking for info about gun bore angle for 60cm and 54cm guns of Mörser Karl Gerät.
Thank you for help

I'm not quite sure I understand the question, but if you're asking about max QE, it was 70 degrees.

Hi,
I thought barrel riffling lines.

I want to let open breech for view through the gun barrel.

Barrel twist is measured as a ratio. For example, 1:7, 1:9... That said, none of my artillery references state the ratio for the Karl. My guess, given the mass of the projectile, is that the ratio is very slight, ie, larger second number.

I think you are asking the max QE or quadrant. This is the elevation,in the US Arty it wiuld be expressed in mils. Mils are a much finer unit of measurement than degrees. If the grey cells are woking a degree has approx 17 mils. Then you ad or deduct FORKS , forks compensate for the difference in altitude/height between the gun and the target. Then there is cant ,to correct for the slope of the ground upon which the gun is sitting.

I have a 1/35 MORSER THOR,KARL,LOKI ETC with a munitions schlepper. I would be very interested in following your build. Good Luck!