Sideplate Observations

Dwight Gruber · 09-03-2008, 05:03 PM

Quote:

Originally posted by Imperial Arms
... In many cases, the sideplate will have a slightly different tone of blue than the rest of the pistol which is obviously noticeable on this pistol ...

Sideplates seem to be made of a different quality of steel from the rest of the gun. In response to a question several years ago, Thor mentioned that sideplates "take" blue differently--more quickly--than the rest of the gun. We have all seen examples where an otherwise correct and matching sideplate's surface has deteriorated much faster than the rest of the gun.

--Dwight

Vlim · 09-03-2008, 05:48 PM

It would be interesting to check if this discoloration is also present on Mauser made P08's, and certainly after they changed the blueing process.

The reason: According to original Mauser factory documentation dating from 1937, the side plate was made from the same steel as the frame.

Ron Wood · 09-03-2008, 10:14 PM

Gerben,
The difference in color of the side plate is something I have observed and wondered about. Given that it is the same alloy as the frame I suspect that the color may be due to different heat treating and the fact that the final sanding of the side plate is oriented vertically as opposed to the horizontal striations of the receiver...sort of a moirÃ?Â© effect.

Vlim · 09-04-2008, 09:06 AM

Ron,

Good theory. The different (and quicker) wear of the blue is visible on my 1913 KNIL and 1917 DWM LP08, so I'm a 'believer' when it comes to side plate discoloration.

Here they are side by side (please ignore the VoPo grips, they're for handling purposes only):

It also helps to repeat the VoPo grip tip for owners of grip safety shooters:
The grips are hollow and are ideal for a grip safety conversion.

John Sabato · 09-04-2008, 10:54 AM

I concur with Ron's assessment of the heat treating being a likely suspect in the manner in which the sideplate takes it's blue differently than the majority of the gun's parts.

I also think that this part receives some very heavy machining operations for it size, weight, and construction and that the heavy machining to size may also alter the surface grain of the steel to where it finishes differently than the rest of the gun.

I was not sure if the sideplate is made from exactly the same alloy as the gun either...

Gerben, does the documentation that you have specify the steel type? and do you have anything on what processes were used to heat treat the various parts for hardening?

Vlim · 09-04-2008, 11:23 AM

John,

It's only given as 'Steel type St 50.11' and that is was a forged part ('schmiedeteil').

John Sabato · 09-04-2008, 11:49 AM

Gerben, does your documentation state the upper receiver and the grip frame forged originally? ... I know the Mauser reproductions were... or were they billet steel that was machined? Simply that difference would be enough for the blueing to be different in the same processes.

Vlim · 09-04-2008, 12:12 PM

John,

The 1937 receiver and complete toggle were made from similar steel and were machined from raw forgings. Steel type St C 25.61.

The toggle front-end was machined from a standard 5 meter long DIN-sized (DIN 1011)forged steel bar of 22x18mm in diameter, also of steel type St C 25.61. They were able to make 92 toggle fronts from this 5 meter bar.

The postwar Mauser Parabellum receiver was made from a forged part (I've inspected a raw forging in Oberndorf), as was the toggle front-end. The mid toggle and rear toggle pieces were castings.

09-03-2008, 10:14 PM	#3
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: 7,020 Thanks: 1,090 Thanked 5,174 Times in 1,701 Posts	Gerben, The difference in color of the side plate is something I have observed and wondered about. Given that it is the same alloy as the frame I suspect that the color may be due to different heat treating and the fact that the final sanding of the side plate is oriented vertically as opposed to the horizontal striations of the receiver...sort of a moirÃ?Â© effect. __________________ If it's made after 1918...it's a reproduction

09-04-2008, 10:54 AM	#5
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,154 Thanks: 3,003 Thanked 2,306 Times in 1,097 Posts	I concur with Ron's assessment of the heat treating being a likely suspect in the manner in which the sideplate takes it's blue differently than the majority of the gun's parts. I also think that this part receives some very heavy machining operations for it size, weight, and construction and that the heavy machining to size may also alter the surface grain of the steel to where it finishes differently than the rest of the gun. I was not sure if the sideplate is made from exactly the same alloy as the gun either... Gerben, does the documentation that you have specify the steel type? and do you have anything on what processes were used to heat treat the various parts for hardening? __________________ 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..."*

09-04-2008, 11:49 AM	#7
John Sabato Lifer Lifetime Forum Patron Join Date: Jun 2002 Location: The Capital of the Free World Posts: 10,154 Thanks: 3,003 Thanked 2,306 Times in 1,097 Posts	Gerben, does your documentation state the upper receiver and the grip frame forged originally? ... I know the Mauser reproductions were... or were they billet steel that was machined? Simply that difference would be enough for the blueing to be different in the same processes. __________________ 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..."*

09-03-2008, 05:48 PM	#2
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,053 Thanks: 1,036 Thanked 3,988 Times in 1,205 Posts	It would be interesting to check if this discoloration is also present on Mauser made P08's, and certainly after they changed the blueing process. The reason: According to original Mauser factory documentation dating from 1937, the side plate was made from the same steel as the frame.

09-04-2008, 09:06 AM	#4
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,053 Thanks: 1,036 Thanked 3,988 Times in 1,205 Posts	Ron, Good theory. The different (and quicker) wear of the blue is visible on my 1913 KNIL and 1917 DWM LP08, so I'm a 'believer' when it comes to side plate discoloration. Here they are side by side (please ignore the VoPo grips, they're for handling purposes only): It also helps to repeat the VoPo grip tip for owners of grip safety shooters: The grips are hollow and are ideal for a grip safety conversion.

09-04-2008, 11:23 AM	#6
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,053 Thanks: 1,036 Thanked 3,988 Times in 1,205 Posts	John, It's only given as 'Steel type St 50.11' and that is was a forged part ('schmiedeteil').

09-04-2008, 12:12 PM	#8
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,053 Thanks: 1,036 Thanked 3,988 Times in 1,205 Posts	John, The 1937 receiver and complete toggle were made from similar steel and were machined from raw forgings. Steel type St C 25.61. The toggle front-end was machined from a standard 5 meter long DIN-sized (DIN 1011)forged steel bar of 22x18mm in diameter, also of steel type St C 25.61. They were able to make 92 toggle fronts from this 5 meter bar. The postwar Mauser Parabellum receiver was made from a forged part (I've inspected a raw forging in Oberndorf), as was the toggle front-end. The mid toggle and rear toggle pieces were castings.