Blasting of Lugers during refinishing

[ithacaartist]

Happy Holidays, all...

While examining my shooter collection under magnification, I discovered that 3/5 of them display tiny peen marks indicating they have been blasted with some medium or other before the bluing was reestablished. The two '06 AEs and the 1917/1920 military P.08 were all treated this way. My 1917 LP.08 and Mauser Parabellum 29/70 are original finish, not showing evidence of this process.

My question is: Under what circumstances, other than modern re-dos, was blasting used by Luger manufacturers/arsenal reworks? Did they have a selection of media? What might be the time frame for use of the process--when devised, first commonly used, when and why used, etc.?

My impression is that it was not used in the original finishing of Lugers, but to clean them up for resale or re-issue. I can imagine importers and surplus outfits did this to improve their looks, and am wondering which category the work that was done to mine might fall into.

Another question is (a little off topic): What exactly is the finish that was applied to the Erma La/Ep .22s? It looks closer to the heavy dark bluing of the 29/70 Mauser, but was applied over diecast, of course, in this case.

David Parker

[alanint]

I can comment on the .22 Erma pistols.
They are finished with a heavy, baked on enamel, not unlike some more modern pistols and SMGs.

[lugerholsterrepair]

David..display tiny peen marks

If these are exactly as you say it is an indication of glass bead blasting. That is a relatively modern method.

[DavidJayUden]

It sounds like what is offered as a matt blue finish. No buffing is required, just blast it and blue it (or black oxide) for a darker, almost matt black finish. Cheaper to do because less labor-intensive. I've only seen it done in conjunction with salt-bluing.
It does make a nice finish, just not "Luger nice".
dju

[Freischütz]

I remember reading that someone simulated rust bluing by bead blasting and then applying modern hot blue. The bead blasted surface reflected the light differently.

[ithacaartist]

Thanks for the responses so far. I'm thinking it will be difficult to remediate the blasting marks, as they extend everywhere, even to the depths of the stamped numbers and proofs. Nobody bothered to smooth out the surface beforehand, so they are also evident on the little dings and scratches that existed before refinish. To smooth out the peening to a #400 or thereabouts finish will be difficult on all but broad surfaces, because of their universal presence; all else would seem to risk the sharpness of the edges--particularly those raised by stamping.

Doug, that's the answer I hoped for/expected. As long as I'm spiffing up the Ermas, I might give them a trip to the powder coater's. A very thin yet very durable formulation is available.

[Vlim]

Several parts of the 1970s Mauser Parabellum were actually sandblasted during production.
Production step 735, part 1, shows that the front parts of the frame were to be sandblasted (Sanstrahlen).