One of the first surprises examining the new bolts is the manner of finishing on the bolt body. The round out side diameter surfaces are all ground. Next to the bolt guide and locking lug a wheel with a radius dressed into it was used and transversed length wise to get the round diameter next to the guide and lug, other round surfaces a conventional cylindrical grinding pattern is observed. On the mostly unused bolt I can discern the same marks now that I know what I am looking for.
Next surprise the locking lug's working surface is NOT ground. It shows machine marks as well as the case hardened surface. This will give a way of guessing at wear of the bolt.
The first attached photo shows a bolt that has not been used in 80 years as well as one of the new bolts. The lightly used lug shows a shiny spot (circled) covering about 20 to 25% of the surface. So most of the lug has never touched the corresponding surface of the receiver. This bolt has an s12 mark on the rear. This is too few samples to be sure but a wild guess would say the s## may indicate a .0004" or .01mm increment.
Surprise #3 the new bolts have a number of dings. A ding besides having a indentation will have raised metal on the sides which could roughen the perceived feel and wear the receiver. I circled them with a marker and found 7 on one and 13 on the other. Made me wonder if they came from storage or SA, then I looked over my 2 bolts and they had dings also, most have had at least a portion of the raised material worn off. So I am going to say the dings came from the arsenal and not from Grandpa's. The packaging and box from Grandpa's were completely adequate. I will touch all of them up with a Cratex wheel in a Dremel tool. The grit from this kind of operation is one that will keep on giving so clean up afterwards is most important. On the photos with the dings circled the new ones are on the left and the most worn one on the right. The used bolts have 10 and 3 dings respectively.

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