Don't have a clue on what is recommended. I always torque my stuff to quote a friend of mine "using the German torque wrench Goodentight. But I also always put blue loctite on any mounting or retention system. Blue Loctite is critical in any mounting.
However, not sure if you know this but the Pulsar Trail Line including your 50 has a horrible track record of maintaining POA/POI due to the housing shrinking and swelling during temperature changes.
Yes, I have some buds that run them and have zero complaints. However, they are hog hunters and start out usually at 50 yards so the shift is likely not much of an issue for them. Plus the way some of em shoot, a little bit of POA/POI variance on running hogs might actually help some of em score more hogs.