Trying to get this 51 to cycle manually and when the bolt comes back ~.5" it stops. If I rotate the bolt with my finger it will complete it rotation and allow it to unlock from the barrel cuts and cycle. I've clean it thoroughly and inspected for burrs, Knicks, and wear marks. The bolt buffer is in place. If I take the slide assembly with bolt attached out of the gin and try to work it on the barrel I still get the same result.
I've read this model tends to have a lot of issues so maybe someone can share their expertise.