Right shoulder tightness in squat

[Bodybeing]

Hi,
I'm about 6 weeks into SS. My squats are progressing slow and steady, from empty bar (20kg) at start I'm now at 57.5kg for 3x5. In the book SS Rip says that if there is any shoulder tightness then it should work itself out in a few weeks. It hasnt.

Basically when I assume the starting position I cannot retract my right elbow back and up as far as my left. I don't know if this is because of tightness in the muscles on my back or front or where... The upshot of this is that although I can get my elbows back to the rear and the bar on my spine of scapula, my wrists aren't in a neutral position but are in hyperextension. If I straighten them the bar rolls up to a high bar position.

Since this problem doesnt seem to be resolving itself, I thought I would ask:
what muscles are probably tight and which stretches should I specifically do to help them?

[Rusi]

According to Rip shoulder dislocations help with similar situation. At the same time you can try to use wider grip. I know that in SS Rip suggest to stay between the rings of the bar but for me that's insanely close position. I usually place my index fingers on the rings. It works for me. Hyper-extending the wrist when you hold the bar does not always mean that you are supporting the bar with your wrist. I think that moderate hyperextension of the wrist is ok and unavoidable sometimes. Just make sure you use thumbless grips and make sure that your elbows are up and your chest is not caved in order to support the weight with your upper back and delts.