Yes, I called S&W on the phone, they gave me the date of manufacture and then said that .357 is fine but to not shoot +P out of any gun that is not marked +P.
I have a model 19 S&W .357 and I was told on the customer service line not to use +P ammo in it. The CUP difference between +P and .357 is 15,000 psi. What gives?
Looks like you have everything you need. A sweet looking rifle. As far as the spring noise, that tells you the buffer is working and I have never had an AR without it in some form or another.