When I was swapping to the SBH hammer on my New Vaquero, I managed to get the "pointy bit" on that spring alongside the loading gate pivot point instead of jammed up underneath it like it's supposed to be. That compromized the loading gate "stiffness" something awful. Took me a sec to realize what had happened and re-seat the end of the spring and then all was OK.
I'm thinking either there's crud in there, or the end of the spring is bent funny and isn't hitting the gate where it should, or the spring is worn out. In two out of three of those situations having another spring in hand would be worthwhile and since they're under $6 a piece, worth scoring another just in case.
Even if you also bought a Brownell's Ruger-specific screwdriver kit for less than $20 at the same time, it will be easier, cheaper and faster to do this fix yourself versus sending it in to Ruger. The spring and screwdriver kit together will cost less than one-way shipping on the whole gun.
Rugers respond very well to "kitchen table gunsmithing", it's a testament to the sanity of the basic design.