Both of my blued models have the eagle on stainless bolts. I got a killer deal on mine. Gunshop was going out of business and I got mine for $197.00 each plus tax. Both remain unfired. Is your bolt blued or stainless ?
Sounds like maybe somebody at the gunshop switched bolts before you got it. Or maybe Ruger ran out of stainless eagle bolts and used some blued ones to keep selling guns I wonder how many other 50th models out there have the more common blued bolts ?
The bolt has been swapped out for a standard one by someone who correctly thought it would look better in their regular blued version. I have seen lots of these and own a few and they ALL have had the stainless bolt with the Ruger logo stamped on the back end. You have a great little shooter none-the-less, so put some rounds through it!...but don't hold your breath on keeping that as any type of collector.....not that the 100% correct ones are any such thing in themselves. Enjoy it.
I have others also. I bought one of the 50th year ones just to get the stainless bolt for a NIB 5-1/2 inch stainless MKII that I am customizing. I also bought some fancy pewter metal grips for it. The one I rob the bolt out of will go to my granddaughter in a few years as a shooter.