Even though I wasn't aware of this tendency until after selecting one on Aug. 31st, something tonight caught my attention.
The action inscribed with 560****, the top of the bolt shows 652****.
Why do people claim that the CMP Specials are all matching, other than the new wood, or is the bolt always an exception?
Rondog pretty much, as mentioned, covered it well. You are looking at drawing numbers for the parts. Those drawing numbers determine if a rifle is correct for a given serial number. Since you only provide the first three digits of the serial number it is hard to call but here is a guess.
Serial Number 5104106 and up...........
Receiver Dwg. # D6528291-E
Receiver Heat Lot # NONE
Barrel Side Markings P LMR D6535448 1 55 A39 P M
Bolt Dwg. # 6528287 IHC
Heat Lot # D19
Operating Rod Dwg. # 6535382 IHC
Operating Rod Catch: X
Clip Latch: C Inside Near Spring Hole
Gas Cylinder Lock: High Hump
Gas Cylinder Lock Screw: P X
Trigger Housing: 6528290 IHC
Trigger Guard: Stamped, without milled hook.
Hammer: 5546008IHC
Safety: F
Bullet Guide: Stamped With Notch
Front Sight: 7/8" Wide
Rear Sight Elevation Knob: IHC
Rear Sight Windage Knob: IHC DRC
Rear Sight Base: C
So what makes a M1 Garand correct is having the correct parts by DWG. # as compared to the serial number on the receiver which indicates year of manufacture. Needless to say an IHC rifle with a SA trigger housing would be incorrect. The Post WWII rifles are pretty easy to match up as to correct parts, the guy with a 1942 Winchester? Good luck!
Again, what I listed are "guesstimates" based roughly on the SN information you provided. Also, as it pertains to IHC manufacture rifles. Saw Rondog's post 5 and remembered I should mention that.
Ron