Does anyone know if the sako 85 with the syn stock and metal trigger guard would fit the barrel of the tikka t3 stainless

No it won't. They are entirely two different bedding systems. The Tikka T3 utilizes a lug in the stock which mates to a matching notch in the receiver. The bedding in the Sako stock is flat to mesh with the flat bottomed receiver.

thanks for the info