What's the original spec's on barrels???

G.T. · 04-15-2004, 09:13 PM

Hi to all! I have seen many luger barrels, and also, the little 8.8x stamps on the bottom of the barrel, I never really did the math, just used to look at them for correctness! Now I'd like to know?? What was the original bore dia. (most common) and the direction and rate of twist on original 9mm P.08 barrels??? If someone desired it, what twist would be best for cast 9mm bullets?? Who makes the most comparable blank to the originals today?? I priced a few blanks that I found just <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" /> <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" /> surfing the net! Holy Schnikies!!! They were prohibitivly expensive!! Anyone have some good leads on reasonably priced blanks! best to all! til...lat'r....GT

Vlim · 04-16-2004, 06:41 AM

Hi GT,

Try to get hold of 'The Dutch Luger'. This book has nice 1904 production drawings in them and one of them displays the barrel, grooves, etc...

John Sabato · 04-16-2004, 11:12 AM

GT,

I don't know how good your German is, but the answer to your questions are in the blueprint book you just bought... on Page 1 labeled "Der Lauf"

Each Groove width was 2.5mm plus 0.10mm

Groove diameter of the bore was 9.1mm plus 0.01mm or minus 0.03mm
Land diameter of the bore was 8.85mm plus 0.04mm or minus 0.03mm

there was a 6 groove bore with a right hand twist was one turn in 250mm (10 inches) plus or minus 2mm

<a href="http://forums.lugerforum.com/lfupload/barrel_measurements_info.jpg" target="_fullview"><img src="http://forums.lugerforum.com/lfupload/barrel_measurements_info.jpg" width="400" alt="Click for fullsize image" /></a>

Need anything else?

John Sabato · 04-16-2004, 02:23 PM

GT please check your regular email.

Sieger · 04-16-2004, 06:04 PM

G.T.

If you would like to design a proper 9mm barrel, one that would accurately shoot a 115 to 125 grain projectile at a proper speed, I, for one, would be interested.

9mm Parabellum barrels are rather sloppyly fit at .357 to .358 grove diameter. Why so loose?!? We are still trying to find out.

Do humanity a service and take up the challenge.

Sieger

G.T. · 04-16-2004, 07:54 PM

Hi Sieger! I very much would like to make a correct & desired P.08 barrel! Right now, I'm on a fact finding mission, and I need Info. from experienced shooters and reloaders, such as yourself! Drop me an email so we might converse on the charecteristics that would be necessary to produce a barrel like you suggest! I have several others on the forum giving me aid and input so that I might have some parameters to go by.... John S. has been a great help, and is formulating plans and working drawings off of the info. we have from the old tables and drawings... external dimensions are a given.. and pretty straight forward... but, correct, available, high quality, and cost effective blanks of the correct internal dimensions are a whole'noth'er deal! Anyone who has anything to add, or share, please feel free! my total knowledge on barrel blanks is pretty weak right now! Best to all. Til...lat'r....GT <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" /> <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" />

John Sabato · 04-20-2004, 04:21 PM

IF anyone is out there who is pretty familiar within the Class III community, Do you know if there is a readily available (read that as cheap!) replacement Submachinegun barrel that has sufficient bulk to be machined into a Luger barrel?

UZI? Beretta? The widest portion of the Luger barrel is the flange and it generally measures .872 at the largest point...

If there is enough "meat" on one of these barrels, the front sight bast could be salvaged from an old shot out barrel and installed on the end of the appropriate taper...

Anyone know where to get 9mm (.355 bore) rifled barrel blanks at near Luger lengths that don't cost and arm and a leg?

These used to be plentiful and cheap from sources like Gun Parts Corp. (Numrich), but it has been a LOOOOOOONG time since I have seen any.

John Sabato · 04-20-2004, 05:02 PM

thanks for the info and examples Rick. The barrel specs for 9mm Parabellum might be old, but they haven't changed...

Some manufacturers that produce not only 9mm weapons but also .38/.357 caliber might standardize on the large size bore which would be a slightly sloppy fit for standard 9mm slugs, but is good enough to meet the accuracy needs of what they produce... submachine guns for instance, don't require the same accuracy that would be required of a target pistol in 9mm... they make up in quantity what they give up in quality.

If it is going to be off the shelf 9mm ammo in a custom pistol barrel, then the barrel should be the appropriate specs IMHO...

Sieger · 04-20-2004, 05:16 PM

<blockquote>quote:<hr />Originally posted by John Sabato:
thanks for the info and examples Rick. The barrel specs for 9mm Parabellum might be old, but they haven't changed...

Some manufacturers that produce not only 9mm weapons but also .38/.357 caliber might standardize on the large size bore which would be a slightly sloppy fit for standard 9mm slugs
<hr /></blockquote>Hi John:

The original DWM specs. specify a .357 minimum groove allowing up to a .358 groove. The original projectiles were .354. Why the slop?!?

It seems that the newer 9mm firearms have kept the .357 to .358 groove. Again, why the slop?!?

A properly designed "new" barrel should have .355 grooves to fit the projectile!

The 9mm has never been know for its accuracy. Perhaps the sloppy fit is part of the problem (and easily corrected).

Sieger

unspellable · 04-20-2004, 06:19 PM

The rate of twist is the same for cast or jacketed bullets. It's determined mostly by bullet length and velocity. The difference in a barrel optimized for one or the other is in the profile of the rifling itself.

It would be interesting to try a barrel sized to the ammo. I suspect that with a good bullet/barrel fit, a trigger job, and sights, the Luger would be a real tack driver.

Sieger and I have been working on some aspects of this. We still do not have a definite answer as to why the barrels are oversized. I have one explanation but at this stage it's shaky.

Some one gave me a theory on why today's ammo is too short. I'll have to run some calculations and see if it holds water.

unspellable · 04-20-2004, 06:19 PM

PS. All this applies to the 7.65 mm as well as the 9 mm.

G.T. · 04-21-2004, 10:57 AM

John, Rick, Sieger, & unspellable! Thanks for your input! I am starting to get a grasp on what you mean as to different bore dimensions for different reasons! If I made a quality barrel that was basically "made to order" or "made to spec." I would probably stamp the bore designation on the bottom, same as what the Germans did?? I would guess the bore dimension varied greatly on the originals, why would they mark them otherwise?? I would be interested in the lowest number recorded, (8.8?) and the highest?? What was the original range?? If I were starting today on the project...I would use blanks with a bore measuring .355 ?? More input please! Thanks guys..this is pretty interesting... Sieger, I sent you an email?? Did you get it?? If not, I'll send it again! til...lat'r...GT

John Sabato · 04-21-2004, 11:58 AM

GT, the largest bore on a marked original barrel I have ever seen is 8.85.. but the specs in my diagram above allow for as high as 8.86mm

8.85 = 0.3540 inches
8.86 = 0.3544 inches

The lowest I have ever seen is 8.82mm and this is also the low end of the specs above and calculates to 0.3528 inches on the low end.

".357" caliber converts to 9.067799999999998 mm

and .356 converts to 9.042399999999998

...both of which are out of spec according to the original 1913 blueprint that I have posted the extract from... but the question here is: Does the American .357 caliber refer to the land or groove diameter?

The land diameter of the 1913 blueprints is 9.1mm and that converts to 0.364 inches...

Sieger · 04-21-2004, 05:34 PM

Dear John:

There has been a lot of confusion regarding the method the Europeans typically spec. things and the way we do.

The conversion formula for MM to inches is:

MM X .03937 = inches

Bore size (land to land) per 1913 Specs. as quoted above:

Maximum 8.86mm X .03937 = .3488 inch

Minimum 8.82mm X .03937 = .3472 inch

Groove size (groove to groove) per the 1913 Specs. as quoted above:

Maximum 9.11mm X .03937 = .3587

Minimum 9.07mm X .03937 = .3571

The 1904 DWM Catalogue I have states the diameter of the 9mm projectile at 9.02mm, or .3551 inches.

In the US, we typically quote a bullet size by its diameter, (i.e. .357).

Conclusion:

The original DWM spec. bullets were made .002 inches smaller than the barrel's minimum allowable groove diameter and .003 smaller than its maximum allowable diameter.

The question is why was this done?

Sieger

unspellable · 04-21-2004, 06:15 PM

GT,

Contrary to the popular myth, the barrel caliber and groove dimensions in the original Parabellums do not vary much, they were held to tight tolerances.

Bore and caliber both properly refer to the diameter between lands. This because the bore is the original hole bored in the barrel before the rifling is cut. The caliber refers to the size of ball that can be passed through the barrel without being cut by the rifling, in other words the same as the bore. (Except in muzzle loading cannons where caliber is length of the barrel divided by the bore, a ratio, and has nothing to do with the size of the bore and more to do with how long the piece is.)

The American 357 as in 357 Magnum refers to the groove diameter.

To further the confusion, the 30-06 is a 30 caliber but the 308 is also a 30 caliber with the exact same dimensions. Both take a 308 bullet. You will go nuts trying to make sense of cartridge designations.

04-15-2004, 09:13 PM	#1
G.T. Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: Chandler Arizona Posts: 3,486 Thanks: 1,284 Thanked 3,583 Times in 989 Posts	What's the original spec's on barrels??? Hi to all! I have seen many luger barrels, and also, the little 8.8x stamps on the bottom of the barrel, I never really did the math, just used to look at them for correctness! Now I'd like to know?? What was the original bore dia. (most common) and the direction and rate of twist on original 9mm P.08 barrels??? If someone desired it, what twist would be best for cast 9mm bullets?? Who makes the most comparable blank to the originals today?? I priced a few blanks that I found just <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" /> <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" /> surfing the net! Holy Schnikies!!! They were prohibitivly expensive!! Anyone have some good leads on reasonably priced blanks! best to all! til...lat'r....GT

04-16-2004, 11:12 AM	#3
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,152 Thanks: 3,003 Thanked 2,304 Times in 1,096 Posts	GT, I don't know how good your German is, but the answer to your questions are in the blueprint book you just bought... on Page 1 labeled "Der Lauf" Each Groove width was 2.5mm plus 0.10mm Groove diameter of the bore was 9.1mm plus 0.01mm or minus 0.03mm Land diameter of the bore was 8.85mm plus 0.04mm or minus 0.03mm there was a 6 groove bore with a right hand twist was one turn in 250mm (10 inches) plus or minus 2mm <a href="http://forums.lugerforum.com/lfupload/barrel_measurements_info.jpg" target="_fullview"><img src="http://forums.lugerforum.com/lfupload/barrel_measurements_info.jpg" width="400" alt="Click for fullsize image" /></a> Need anything else? __________________ regards, -John S "...We hold these truths to be self-evident that ALL men are created EQUAL *and are endowed by their Creator* with certain UNALIENABLE* rights, and among these are life, LIBERTY, and the pursuit of happiness..."*

04-16-2004, 02:23 PM	#4
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,152 Thanks: 3,003 Thanked 2,304 Times in 1,096 Posts	GT please check your regular email. __________________ regards, -John S "...We hold these truths to be self-evident that ALL men are created EQUAL *and are endowed by their Creator* with certain UNALIENABLE* rights, and among these are life, LIBERTY, and the pursuit of happiness..."*

04-20-2004, 04:21 PM	#7
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,152 Thanks: 3,003 Thanked 2,304 Times in 1,096 Posts	IF anyone is out there who is pretty familiar within the Class III community, Do you know if there is a readily available (read that as cheap!) replacement Submachinegun barrel that has sufficient bulk to be machined into a Luger barrel? UZI? Beretta? The widest portion of the Luger barrel is the flange and it generally measures .872 at the largest point... If there is enough "meat" on one of these barrels, the front sight bast could be salvaged from an old shot out barrel and installed on the end of the appropriate taper... Anyone know where to get 9mm (.355 bore) rifled barrel blanks at near Luger lengths that don't cost and arm and a leg? These used to be plentiful and cheap from sources like Gun Parts Corp. (Numrich), but it has been a LOOOOOOONG time since I have seen any. __________________ regards, -John S "...We hold these truths to be self-evident that ALL men are created EQUAL *and are endowed by their Creator* with certain UNALIENABLE* rights, and among these are life, LIBERTY, and the pursuit of happiness..."*

04-20-2004, 05:02 PM	#8
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,152 Thanks: 3,003 Thanked 2,304 Times in 1,096 Posts	thanks for the info and examples Rick. The barrel specs for 9mm Parabellum might be old, but they haven't changed... Some manufacturers that produce not only 9mm weapons but also .38/.357 caliber might standardize on the large size bore which would be a slightly sloppy fit for standard 9mm slugs, but is good enough to meet the accuracy needs of what they produce... submachine guns for instance, don't require the same accuracy that would be required of a target pistol in 9mm... they make up in quantity what they give up in quality. If it is going to be off the shelf 9mm ammo in a custom pistol barrel, then the barrel should be the appropriate specs IMHO... __________________ regards, -John S "...We hold these truths to be self-evident that ALL men are created EQUAL *and are endowed by their Creator* with certain UNALIENABLE* rights, and among these are life, LIBERTY, and the pursuit of happiness..."*

04-16-2004, 06:41 AM	#2
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,049 Thanks: 1,035 Thanked 3,957 Times in 1,200 Posts	Hi GT, Try to get hold of 'The Dutch Luger'. This book has nice 1904 production drawings in them and one of them displays the barrel, grooves, etc...

04-16-2004, 06:04 PM	#5
Sieger User Join Date: Jul 2003 Location: New York, NY Posts: 1,575 Thanks: 2,124 Thanked 400 Times in 249 Posts	G.T. If you would like to design a proper 9mm barrel, one that would accurately shoot a 115 to 125 grain projectile at a proper speed, I, for one, would be interested. 9mm Parabellum barrels are rather sloppyly fit at .357 to .358 grove diameter. Why so loose?!? We are still trying to find out. Do humanity a service and take up the challenge. Sieger

04-16-2004, 07:54 PM	#6
G.T. Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: Chandler Arizona Posts: 3,486 Thanks: 1,284 Thanked 3,583 Times in 989 Posts	Hi Sieger! I very much would like to make a correct & desired P.08 barrel! Right now, I'm on a fact finding mission, and I need Info. from experienced shooters and reloaders, such as yourself! Drop me an email so we might converse on the charecteristics that would be necessary to produce a barrel like you suggest! I have several others on the forum giving me aid and input so that I might have some parameters to go by.... John S. has been a great help, and is formulating plans and working drawings off of the info. we have from the old tables and drawings... external dimensions are a given.. and pretty straight forward... but, correct, available, high quality, and cost effective blanks of the correct internal dimensions are a whole'noth'er deal! Anyone who has anything to add, or share, please feel free! my total knowledge on barrel blanks is pretty weak right now! Best to all. Til...lat'r....GT <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" /> <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" />

04-20-2004, 05:16 PM	#9
Sieger User Join Date: Jul 2003 Location: New York, NY Posts: 1,575 Thanks: 2,124 Thanked 400 Times in 249 Posts	</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by John Sabato: <strong>thanks for the info and examples Rick. The barrel specs for 9mm Parabellum might be old, but they haven't changed... Some manufacturers that produce not only 9mm weapons but also .38/.357 caliber might standardize on the large size bore which would be a slightly sloppy fit for standard 9mm slugs </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Hi John: The original DWM specs. specify a .357 minimum groove allowing up to a .358 groove. The original projectiles were .354. Why the slop?!? It seems that the newer 9mm firearms have kept the .357 to .358 groove. Again, why the slop?!? A properly designed "new" barrel should have .355 grooves to fit the projectile! The 9mm has never been know for its accuracy. Perhaps the sloppy fit is part of the problem (and easily corrected). Sieger

04-20-2004, 06:19 PM	#10
unspellable User Join Date: Jun 2002 Location: Iowa Posts: 768 Thanks: 0 Thanked 19 Times in 11 Posts	The rate of twist is the same for cast or jacketed bullets. It's determined mostly by bullet length and velocity. The difference in a barrel optimized for one or the other is in the profile of the rifling itself. It would be interesting to try a barrel sized to the ammo. I suspect that with a good bullet/barrel fit, a trigger job, and sights, the Luger would be a real tack driver. Sieger and I have been working on some aspects of this. We still do not have a definite answer as to why the barrels are oversized. I have one explanation but at this stage it's shaky. Some one gave me a theory on why today's ammo is too short. I'll have to run some calculations and see if it holds water.

04-21-2004, 10:57 AM	#12
G.T. Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: Chandler Arizona Posts: 3,486 Thanks: 1,284 Thanked 3,583 Times in 989 Posts	John, Rick, Sieger, & unspellable! Thanks for your input! I am starting to get a grasp on what you mean as to different bore dimensions for different reasons! If I made a quality barrel that was basically "made to order" or "made to spec." I would probably stamp the bore designation on the bottom, same as what the Germans did?? I would guess the bore dimension varied greatly on the originals, why would they mark them otherwise?? I would be interested in the lowest number recorded, (8.8?) and the highest?? What was the original range?? If I were starting today on the project...I would use blanks with a bore measuring .355 ?? More input please! Thanks guys..this is pretty interesting... Sieger, I sent you an email?? Did you get it?? If not, I'll send it again! til...lat'r...GT

04-21-2004, 11:58 AM	#13
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,152 Thanks: 3,003 Thanked 2,304 Times in 1,096 Posts	GT, the largest bore on a marked original barrel I have ever seen is 8.85.. but the specs in my diagram above allow for as high as 8.86mm 8.85 = 0.3540 inches 8.86 = 0.3544 inches The lowest I have ever seen is 8.82mm and this is also the low end of the specs above and calculates to 0.3528 inches on the low end. ".357" caliber converts to 9.067799999999998 mm and .356 converts to 9.042399999999998 ...both of which are out of spec according to the original 1913 blueprint that I have posted the extract from... but the question here is: Does the American .357 caliber refer to the land or groove diameter? The land diameter of the 1913 blueprints is 9.1mm and that converts to 0.364 inches... __________________ regards, -John S "...We hold these truths to be self-evident that ALL men are created EQUAL *and are endowed by their Creator* with certain UNALIENABLE* rights, and among these are life, LIBERTY, and the pursuit of happiness..."*

04-21-2004, 05:34 PM	#14
Sieger User Join Date: Jul 2003 Location: New York, NY Posts: 1,575 Thanks: 2,124 Thanked 400 Times in 249 Posts	Dear John: There has been a lot of confusion regarding the method the Europeans typically spec. things and the way we do. The conversion formula for MM to inches is: MM X .03937 = inches Bore size (land to land) per 1913 Specs. as quoted above: Maximum 8.86mm X .03937 = .3488 inch Minimum 8.82mm X .03937 = .3472 inch Groove size (groove to groove) per the 1913 Specs. as quoted above: Maximum 9.11mm X .03937 = .3587 Minimum 9.07mm X .03937 = .3571 The 1904 DWM Catalogue I have states the diameter of the 9mm projectile at 9.02mm, or .3551 inches. In the US, we typically quote a bullet size by its diameter, (i.e. .357). Conclusion: The original DWM spec. bullets were made .002 inches smaller than the barrel's minimum allowable groove diameter and .003 smaller than its maximum allowable diameter. The question is why was this done? Sieger

04-21-2004, 06:15 PM	#15
unspellable User Join Date: Jun 2002 Location: Iowa Posts: 768 Thanks: 0 Thanked 19 Times in 11 Posts	GT, Contrary to the popular myth, the barrel caliber and groove dimensions in the original Parabellums do not vary much, they were held to tight tolerances. Bore and caliber both properly refer to the diameter between lands. This because the bore is the original hole bored in the barrel before the rifling is cut. The caliber refers to the size of ball that can be passed through the barrel without being cut by the rifling, in other words the same as the bore. (Except in muzzle loading cannons where caliber is length of the barrel divided by the bore, a ratio, and has nothing to do with the size of the bore and more to do with how long the piece is.) The American 357 as in 357 Magnum refers to the groove diameter. To further the confusion, the 30-06 is a 30 caliber but the 308 is also a 30 caliber with the exact same dimensions. Both take a 308 bullet. You will go nuts trying to make sense of cartridge designations.