Receiver Measurements - Page 2

MFC · 11-22-2009, 01:50 AM

The difference in value of a 1914 DWM LP08 to any other date LP08 is at least $10,000. The date could be filled by welding it. Then filed/sanded down to the original surface. Welding is commonly used to fill pits during a restoration. Measuring the chamber height wouldn't matter in this case.

Mauser720 · 11-22-2009, 07:16 AM

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 · 11-22-2009, 09:06 AM

Quote:

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...

Quote:

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.

Quote:

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!!!

Quote:

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...

Mauser720 · 11-22-2009, 03:28 PM

Postino -

Thanks for the advice on verniers.

I'm away now for Thanksgiving; however, when I get back, I'm going to buy a good vernier and will get back to you with measurements for the 8 or 10 Lugers I own. I have some cheap verniers, but for something like this I want to be as precise as possible and don't mind spending some money to get a good one.

I think while we are at it, we probably should keep track of serial numbers too. It may be better to keep track of them now then to have collected data and then realize too late that we wish we had kept serial numbers too.

MFC - Mike: Short-wave ultra violet light can be used to detect differences in patination in certain materials such as stone. This is not the same as Long-wave ultra violet light or "blacklight." And short-wave ultra violet light can also damage your eyes if you expose them directly to it. I have not had an opportunity to try this yet on a "suspicious" Luger; however, I suspect that short-wave ultra violet light will indeed reveal the use of welding to fill in a stamped date or a proof mark or modified crest, etc. I have and use these lights. Eventually I need to find someone who has a receiver that they would be willing to have me look at in this manner but for now Postino and I are just going to collect measurements.

Thank you for your insights.

Ron Wood · 11-22-2009, 05:18 PM

I am wondering if you could "pad" the jaws of the caliper with thin electricians tape to preclude any possibility of scratching the gun, and then "zero out" the caliper before taking the measurements? I would not think that the tape would compress enough to affect the measurement. Just a thought.

sheepherder · 11-22-2009, 05:32 PM

Quote:

Originally Posted by Ron Wood

I am wondering if you could "pad" the jaws of the caliper with thin electricians tape to preclude any possibility of scratching the gun...

Ron -

I would think that would only be a problem with a micrometer, not the caliper/vernier...The caliper/vernier will "zoom" in and out with thumb pressure on the travel wheel and you can read it while holding it against the receiver without moving it...while the mic needs to be moved in & out to get an accurate read...

A bit off topic, but here's another tipoff that someone has altered a serial...This is my Russian capture P38...You can see that the edge of the grip frame shows correct mill cutter tool marks, while the end of the slide and the base of the barrel show a fine ground surface...Someone has very painstakingly ground off a very shallow portion of these two surfaces...almost certainly to stamp the new serial...which is stamped very shallowly also...

sheepherder · 11-22-2009, 06:13 PM

BTW...Since some of us are cops, truckdrivers, accountants, and gourmet chefs...Here's a pic of a couple tools I use...my dial caliper (also called a dial vernier), two 1" micrometers, and a machinists spirit level (degree gradations are on other side)...The Brownie mic was my dads; the silver one I got at a flea market basically for pocket change...The mics are dusty and somewhat "patina'ed" from not being used for...decades...because of the dial vernier/caliper...The machinists level I got off eBay; I use it for installing barrels and front sights...

The micrometers work just like a "C" clamp; you hold the anvil against the work and twist the barrel down until the spindle hits the other side of the work...and slide it back and forth just putting very slight pressure against the work......

The dial caliper you can just push the jaws against the work and read the dial...and then release the jaws...

Disclaimer:...I am not a great machinist...At times I am a good machinist...Mostly I am a "good enough!" machinist...

(As in "Good enough for government work!")

Neil Young · 11-22-2009, 06:39 PM

Gentlemen:
My measurements are as follows:

"G" date, 7158a: "A"--0.875"; "B"--0.969".

BYF42, 3732f: "A"--0.871"; "B"--0.968".

Neil Young

sheepherder · 11-22-2009, 09:27 PM

OK: I went back and re-measured all five of mine...This time I made sure I was *not* measuring across a date, or a number on the lug, or across a dent or ding...and I got several different measurements...so the letters/numbers and any dings or dents will affect the accuracy of the measurements...

I also made sure I was as close as perpendicular to the horizontal plane as possible...I noticed that if I went just a bit off 90º that the measurement would change...

The receivers are "fatter" on the sides than on the top/bottom...So the least measurement will be 90º from horizontal...or straight up & down...That's the one we want...

Mauser720 · 11-23-2009, 10:54 AM

Neil Young - Thank you for the measurements. I've added them to our list.

Mauser720 · 11-23-2009, 10:59 AM

QUESTION: Is there any member of this Forum who has education and experience as an OPERATIONS RESEARCH ANALYST?

If so, please send me a private message on this Forum, and I will explain what role you can play in this effort. Thank you!

Hugh · 11-23-2009, 05:15 PM

Just turned 73 today and my old brain gets kinda fuzzy at times, but if I remember correctly, the DWM "alphabet commercial" Lugers were made from war time Lugers, and the date was removed from the top of the reciever by DWM. If you look at one of them from the muzzle, you can see where the top of the receiver is thinner than on a dated Luger. I haven't measured one, and the receiver still stands proud of the bbl flange, but it definitely has a "flatter" contour than the dated guns.

So, couldn't you compare the measurements of an alphabet commercial to a dated Luger to determine how much metal has to be removed to remove the date?

Vlim · 11-23-2009, 05:20 PM

Hugh, good idea.

A measurement of the depth of a typical year marking compared to the receiver thickness.

Mauser720 · 11-23-2009, 11:09 PM

Hugh -

HAPPY BIRTHDAY!

Excellent idea. Thank you.

11-22-2009, 01:50 AM	#21
MFC User Join Date: Sep 2006 Location: Louisiana Posts: 1,237 Thanks: 183 Thanked 281 Times in 162 Posts	The difference in value of a 1914 DWM LP08 to any other date LP08 is at least $10,000. The date could be filled by welding it. Then filed/sanded down to the original surface. Welding is commonly used to fill pits during a restoration. Measuring the chamber height wouldn't matter in this case. __________________ Mike C.

11-22-2009, 07:16 AM	#22
Mauser720 User Join Date: Aug 2007 Location: Kansas Posts: 535 Thanks: 18 Thanked 49 Times in 33 Posts	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! __________________ Mauser720 - Ron "Those who do not know history are doomed to repeat it."

11-22-2009, 03:28 PM	#24
Mauser720 User Join Date: Aug 2007 Location: Kansas Posts: 535 Thanks: 18 Thanked 49 Times in 33 Posts	Postino - Thanks for the advice on verniers. I'm away now for Thanksgiving; however, when I get back, I'm going to buy a good vernier and will get back to you with measurements for the 8 or 10 Lugers I own. I have some cheap verniers, but for something like this I want to be as precise as possible and don't mind spending some money to get a good one. I think while we are at it, we probably should keep track of serial numbers too. It may be better to keep track of them now then to have collected data and then realize too late that we wish we had kept serial numbers too. MFC - Mike: Short-wave ultra violet light can be used to detect differences in patination in certain materials such as stone. This is not the same as Long-wave ultra violet light or "blacklight." And short-wave ultra violet light can also damage your eyes if you expose them directly to it. I have not had an opportunity to try this yet on a "suspicious" Luger; however, I suspect that short-wave ultra violet light will indeed reveal the use of welding to fill in a stamped date or a proof mark or modified crest, etc. I have and use these lights. Eventually I need to find someone who has a receiver that they would be willing to have me look at in this manner but for now Postino and I are just going to collect measurements. Thank you for your insights. __________________ Mauser720 - Ron "Those who do not know history are doomed to repeat it."

11-22-2009, 05:18 PM	#25
Ron Wood Moderator 2010 LugerForum Patron Join Date: Jun 2002 Location: Santa Teresa New Mexico just outside of the West Texas town of El Paso Posts: 6,988 Thanks: 1,067 Thanked 5,099 Times in 1,676 Posts	I am wondering if you could "pad" the jaws of the caliper with thin electricians tape to preclude any possibility of scratching the gun, and then "zero out" the caliper before taking the measurements? I would not think that the tape would compress enough to affect the measurement. Just a thought. __________________ If it's made after 1918...it's a reproduction

11-22-2009, 06:13 PM	#27
sheepherder Lifer Lifetime Forum Patron Join Date: Feb 2009 Location: ...on the 'ol Erie Canal... Posts: 8,182 Thanks: 1,398 Thanked 4,440 Times in 2,328 Posts	BTW...Since some of us are cops, truckdrivers, accountants, and gourmet chefs...Here's a pic of a couple tools I use...my dial caliper (also called a dial vernier), two 1" micrometers, and a machinists spirit level (degree gradations are on other side)...The Brownie mic was my dads; the silver one I got at a flea market basically for pocket change...The mics are dusty and somewhat "patina'ed" from not being used for...decades...because of the dial vernier/caliper...The machinists level I got off eBay; I use it for installing barrels and front sights... The micrometers work just like a "C" clamp; you hold the anvil against the work and twist the barrel down until the spindle hits the other side of the work...and slide it back and forth just putting very slight pressure against the work...... The dial caliper you can just push the jaws against the work and read the dial...and then release the jaws... Disclaimer:...I am not a great machinist...At times I am a good machinist...Mostly I am a "good enough!" machinist... (As in "Good enough for government work!") Attached Images

11-22-2009, 06:39 PM	#28
Neil Young Lifer Lifetime Forum Patron Join Date: Jun 2008 Location: Scottsboro, Alabama Posts: 540 Thanks: 546 Thanked 438 Times in 165 Posts	Gentlemen: My measurements are as follows: "G" date, 7158a: "A"--0.875"; "B"--0.969". BYF42, 3732f: "A"--0.871"; "B"--0.968". Neil Young __________________ Neil The hurrier I go the behinder I get. Sometimes it takes me all day to get nothing done.

11-22-2009, 09:27 PM	#29
sheepherder Lifer Lifetime Forum Patron Join Date: Feb 2009 Location: ...on the 'ol Erie Canal... Posts: 8,182 Thanks: 1,398 Thanked 4,440 Times in 2,328 Posts	OK: I went back and re-measured all five of mine...This time I made sure I was *not* measuring across a date, or a number on the lug, or across a dent or ding...and I got several different measurements...so the letters/numbers and any dings or dents will affect the accuracy of the measurements... I also made sure I was as close as perpendicular to the horizontal plane as possible...I noticed that if I went just a bit off 90º that the measurement would change... The receivers are "fatter" on the sides than on the top/bottom...So the least measurement will be 90º from horizontal...or straight up & down...That's the one we want... Attached Images

11-23-2009, 10:54 AM	#30
Mauser720 User Join Date: Aug 2007 Location: Kansas Posts: 535 Thanks: 18 Thanked 49 Times in 33 Posts	Neil Young - Thank you for the measurements. I've added them to our list. __________________ Mauser720 - Ron "Those who do not know history are doomed to repeat it."

11-23-2009, 10:59 AM	#31
Mauser720 User Join Date: Aug 2007 Location: Kansas Posts: 535 Thanks: 18 Thanked 49 Times in 33 Posts	QUESTION: Is there any member of this Forum who has education and experience as an OPERATIONS RESEARCH ANALYST? If so, please send me a private message on this Forum, and I will explain what role you can play in this effort. Thank you! __________________ Mauser720 - Ron "Those who do not know history are doomed to repeat it."

11-23-2009, 05:15 PM	#32
Hugh RIP Join Date: Jun 2002 Location: Southeast Texas Swamp Posts: 2,460 Thanks: 2 Thanked 165 Times in 64 Posts	Just turned 73 today and my old brain gets kinda fuzzy at times, but if I remember correctly, the DWM "alphabet commercial" Lugers were made from war time Lugers, and the date was removed from the top of the reciever by DWM. If you look at one of them from the muzzle, you can see where the top of the receiver is thinner than on a dated Luger. I haven't measured one, and the receiver still stands proud of the bbl flange, but it definitely has a "flatter" contour than the dated guns. So, couldn't you compare the measurements of an alphabet commercial to a dated Luger to determine how much metal has to be removed to remove the date? __________________ *TRUMP FOR PREZ IN '20!*

11-23-2009, 05:20 PM	#33
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,048 Thanks: 1,034 Thanked 3,951 Times in 1,199 Posts	Hugh, good idea. A measurement of the depth of a typical year marking compared to the receiver thickness.

11-23-2009, 11:09 PM	#34
Mauser720 User Join Date: Aug 2007 Location: Kansas Posts: 535 Thanks: 18 Thanked 49 Times in 33 Posts	Hugh - HAPPY BIRTHDAY! Excellent idea. Thank you. __________________ Mauser720 - Ron "Those who do not know history are doomed to repeat it."