Receiver Measurements

[Mauser720]

Postino -

When it comes to math, there are really only three kinds of people: Those who are good at it, and those who are not. I have no idea of how I arrived at a figure of .084 differences for your first set of figures. I see how it should have been .014.

Yes, I agree your second set of measurements are more reliable. And thank you for the picture of how and where the measurements were taken too.

With the variance of only .009 it is initially difficult to imagine that the removal of a date or a crest (for example) could not be detected in this manner.

The people who create Lugers to deliberately fool and defraud collectors do not always use high end examples to do it. Instead, they often buy up the junk and "shooter" examples, and it is these that they transform into highly desirable collectable examples.

So our effort to collect measurements does not (in my opinion) need to focus on the high end guns. Instead, it needs to focus on collecting measurements for the ordinary examples. And we can sort them by year and type.

There are already other ways to create an uproar at a gun show. Pull out your jeweler's loupe to look at a Luger. Ask if you can take it apart and look at the serial numbers. Ask if you can cycle some dummy cartridges through it, etc. Personally, I would only be concerned if a seller or dealer refuses to let you verify that what he is selling is authentic. If someone had a problem with you or I taking a reciever measurement, I would think it is time to walk away from their table. Know what I mean?

A few questions: Where did you get your Starrett dial vernier? Would that be the one you would recommend for a novice like me? Would Brownells be a good source?

Vlim - Once we feel like we have got this project beyond the conceptual stage and are actually collecting data, I would like to involve gunboards too.

Thank you!

[sheepherder]

Originally Posted by Mauser720

With the variance of only .009 it is initially difficult to imagine that the removal of a date or a crest (for example) could not be detected in this manner.

I would tend to agree. Even if a date stamp was only .010" deep, it would still likely be outside the specs if it was removed...but remember to measure off the stamp itself, as the edges of the stamp will raise up...

So our effort to collect measurements does not (in my opinion) need to focus on the high end guns. Instead, it needs to focus on collecting measurements for the ordinary examples. And we can sort them by year and type.

Sounds cool. I'm in.

There are already other ways to create an uproar at a gun show. Pull out your jeweler's loupe to look at a Luger. Ask if you can take it apart and look at the serial numbers.

Those will arouse interest surely; as people will assume you are "on to something", and will linger to see what it is...but pulling out a mic and measuring the chamber hood can only mean that you suspect a fake...Danger Will Robinson!!!

A few questions: Where did you get your Starrett dial vernier? Would that be the one you would recommend for a novice like me? Would Brownells be a good source?

I got my dial verniers some 28+ years ago; one like this will cost you ~$100 now...Mitutoyo makes good tools, too...as do Brown & Sharp, etc...I'd stay away from Sears...I'd check out eBay for a Starrett, as machinists are always upgrading (that's how I got this one!)...

I buy my tooling from Travers online; they send out a 3" thick catalog to me once a year. They list both Starrett and Mitutoyo...

But remember I am old-fashioned; I stick to what I learned with many years ago...Nowadays you can get digital readout verniers that eliminate any chance of your getting the main reading wrong (it happens)...

As I commented, I have mics...but if you are measuring a beautifully blued finish, then a mic may scratch that finish...You 'drag' a mic's anvil across the piece to be measured...and it takes a [very] little practice to get the tension "just right"...

I do know that Brownell's has verniers for reloading; I don't know how precise they are...