Marrakai:

Okay, I tried an experiment of my own. I have some plywood hurricane shutters tacked up on the wall in the garage. Using a level, I scribed a horizontal line, then an intersecting line at 15degrees, and another at 20 degrees. Holding my .400 up with the barrels level, then slowly tipping them up, fired cases won't stay in the gun past 15 degrees.
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