another new 1917 owner.

I just adopted a model 1917 that was the victim of a recent flood. Fortunately it was soaked with WD-40 immediately after re3covery to dissipate the water and prevent damage to it.
Once it was in my possession, i detail striped it and proceeded to clean everything. some hot soapy water removed 80% of the grime build up on the wood work. The metal is all in great shape. the bore is excellent. It is a Remington receiver made in august of 1918. it did go through the rebuild process at the San Antonio arsenal.
My big question is what is the twist rate of the barrel? HS 4 groove.
second, is it common for the front sight to be loose? The tenon for mine is a little short and allows the front sight to shift front to back.