Luger Grip Screw Thread Size

gvt1911 · 02-22-2017, 01:17 PM

I have a few frames that could use a clean out of the grip screw threads...Does anyone know the correct size tap/s to buy..??? GPC lists their replacement grip screws as M5 x 0.8 pitch ....???
TIA

Norme · 02-22-2017, 01:40 PM

It's an obsolete Whitworth thread, good luck finding a tap!
Norm

mrerick · 02-22-2017, 02:06 PM

Some info here:

http://www.practicalmachinist.com/vb...screws-221376/

John Sabato · 02-22-2017, 02:14 PM

Quote:

Originally Posted by mrerick

Some info here:

http://www.practicalmachinist.com/vb...screws-221376/

Just a note of interest to readers of this thread...

the User named as "biometrics" in the thread that is linked above by mrerick was ME!

Jim Solomon · 02-22-2017, 02:17 PM

Check with Hugh Clark, I think he has info about the screw size and also possibly a tap. Jim

ithacaartist · 02-22-2017, 06:30 PM

Quote:

Originally Posted by sheepherder

What short memories you people have...

I bought the proper tap about four years ago, at around the time this was discussed back then. It wasn't too hard to find. I'm sure they're still available somewhere, but as Rich suggests, I can't remember the source of mine. Same fate for the info of which Whitworth size and thread it is, as well. John S's blueprints reveal it, I'm sure.

gvt1911 · 02-22-2017, 07:42 PM

I believe the following will "work"....

http://www.tapsndies.com/tap/tap-3-16-30.html

G.T. · 02-22-2017, 08:11 PM

Hi Joe, if you're going to order some, get me a set as well? Or, if only one, get the taper tap? I guess depends on cost... but, I'm in if you want to do the ordering?....GT....

G.T. · 02-22-2017, 08:19 PM

Hi to all, ...

....I know it seems kind of rude to randomly request a member buy something for you... and that is not what I want to convey, I have some history with Joe.. so I think, maybe, it's ok?...

... we shall see! ... best to all, til...lat'r...GT...

Chickenthief · 02-23-2017, 06:14 PM

http://www.tracytools.com/taps-and-d...roduct_id=1057

ithacaartist · 02-23-2017, 06:34 PM

Quote:

Originally Posted by Chickenthief

http://www.tracytools.com/taps-and-d...roduct_id=1057

That's the ticket! ...if they export to the US.

It also appears that the threads are larger diameter than the shank, which is handy for getting the best shot at restoring the threads while minimizing the material removed. I recommend running completely through the good thread and chasing the buggered one from the inside out.

DonVoigt · 02-26-2017, 11:55 AM

Quote:

Originally Posted by G.T.

Hi to all, ...

....I know it seems kind of rude to randomly request a member buy something for you... and that is not what I want to convey, I have some history with Joe.. so I think, maybe, it's ok?...

... we shall see! ... best to all, til...lat'r...GT...

GT,
I'll see if the "British" seller will ship here.
If so I'll get at least 3 or 4 taps.

If the answer is yes, I'll start a new thread and see if others want one also.

But in the mean time, the difference in 55 and 60 degree threads will not be significant for the 3 threads of that diameter in the frame.
So if you have/buy a current std 30TPI , it should be just fine.

Chickenthief · 02-26-2017, 02:56 PM

My link is to tap/die in correct 3/16" diameter 30 TPI Withworth 55deg thread form.
What more do you need?

http://www.tracytools.com/taps-and-d...roduct_id=1057

CAP Black · 02-26-2017, 08:29 PM

The Whitworth tap for Luger grip screws is not obsolete. There seems to be enough help provided to make a purchase, if not I will see if I can find my data for the right tap. But a little tip to help: If one side of frame hole is O.K. start the tap from that side and go through the mag well into the damaged side (after applying a drop of oil, of course) and re-thread the side needing straightened out. Slow and easy is a key.
Jack

DonVoigt · 02-26-2017, 10:13 PM

Quote:

Originally Posted by Chickenthief

My link is to tap/die in correct 3/16" diameter 30 TPI Withworth 55deg thread form.
What more do you need?

http://www.tracytools.com/taps-and-d...roduct_id=1057

Since they are in the UK, do you know if they ship to the US and the shipping charge?

That is what I "need" to know; and thanks much for the link.

CAP Black · 02-26-2017, 10:21 PM

I got mine (Whitworth items) right here in West Virginia. They might still be in business.
Jack

CAP Black · 03-03-2017, 01:24 PM

The Whitworth tap, etc. can be purchased at: Sabatelli Precision Grinding, 312 Sabatelli Drive, Mt. Clare, WV 26408. Phone: 304 622-8915.
I don't recall the exact size of the threads or other specs of the opening in Luger grip screw holes.
Jack

Zorba · 03-03-2017, 02:48 PM

Ok, I'm confused. I thought Whitworth was a British thing. Why would the Germans use it? Obviously, there's some factoid I'm missing...

DonVoigt · 03-03-2017, 02:58 PM

The first screw machines they bought were from the UK, at least that is what I read.
Whitworth predates "standardized" metric pitches, IIRC.

The luger screws and threads are a hybrid, metric diameters and TPI. Whitworth is a 55 degree angle thread, the current standard is 60 degrees, so depending on the use/tolerance/number of threads, a 30 TPI Whitworth will "fit"(close enough) a 30 TPI modern thread.

Changing the gearing from TPI to metric is a bear and old "english system" lathes just won't do it.

CAP Black · 03-03-2017, 02:59 PM

Why would it matter to you? Do you want to know the
history of industry in
Europe from the 1700s?
That would be a lot to learn. Many people that come up against this during current times have the same bewilderment.
Let it go.
Also read the thread above and get a portion of it.
Jack

02-22-2017, 01:17 PM	#1
gvt1911 User Join Date: Sep 2016 Location: Mountains of SW Va. Posts: 59 Thanks: 59 Thanked 13 Times in 8 Posts	Luger Grip Screw Thread Size I have a few frames that could use a clean out of the grip screw threads...Does anyone know the correct size tap/s to buy..??? GPC lists their replacement grip screws as M5 x 0.8 pitch ....??? TIA

02-22-2017, 02:06 PM	#3
mrerick Super Moderator - Patron LugerForum Life Patron Join Date: Dec 2009 Location: Eastern North Carolina, USA Posts: 3,900 Thanks: 1,372 Thanked 3,094 Times in 1,503 Posts	Some info here: http://www.practicalmachinist.com/vb...screws-221376/ __________________ Igitur si vis pacem, para bellum - - Therefore if you want peace, prepare for war.

02-22-2017, 02:17 PM	#5
Jim Solomon Lifer Lifetime Forum Patron Join Date: Nov 2012 Location: Georgia Posts: 193 Thanks: 696 Thanked 173 Times in 66 Posts	Check with Hugh Clark, I think he has info about the screw size and also possibly a tap. Jim __________________ Jim Solomon dent2@frontiernet.net

02-22-2017, 08:11 PM	#8
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	Oooohhh! I need some? Hi Joe, if you're going to order some, get me a set as well? Or, if only one, get the taper tap? I guess depends on cost... but, I'm in if you want to do the ordering?....GT....

02-22-2017, 08:19 PM	#9
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	I know this fellow! Hi to all, .......I know it seems kind of rude to randomly request a member buy something for you... and that is not what I want to convey, I have some history with Joe.. so I think, maybe, it's ok?... ... we shall see! ... best to all, til...lat'r...GT...

02-22-2017, 01:40 PM	#2
Norme Always A Lifetime Forum Patron Join Date: Jul 2009 Location: Colorado Posts: 2,415 Thanks: 225 Thanked 2,594 Times in 931 Posts	It's an obsolete Whitworth thread, good luck finding a tap! Norm

02-22-2017, 07:42 PM	#7
gvt1911 User Join Date: Sep 2016 Location: Mountains of SW Va. Posts: 59 Thanks: 59 Thanked 13 Times in 8 Posts	I believe the following will "work".... http://www.tapsndies.com/tap/tap-3-16-30.html

02-23-2017, 06:14 PM	#10
Chickenthief User Join Date: Dec 2016 Location: Denmark Posts: 135 Thanks: 0 Thanked 131 Times in 48 Posts	http://www.tracytools.com/taps-and-d...roduct_id=1057

02-26-2017, 02:56 PM	#13
Chickenthief User Join Date: Dec 2016 Location: Denmark Posts: 135 Thanks: 0 Thanked 131 Times in 48 Posts	My link is to tap/die in correct 3/16" diameter 30 TPI Withworth 55deg thread form. What more do you need? http://www.tracytools.com/taps-and-d...roduct_id=1057

02-26-2017, 08:29 PM	#14
CAP Black User Join Date: Dec 2008 Location: Fairmont, WV Right here in Mountaineer country and God's country Posts: 767 Thanks: 100 Thanked 168 Times in 96 Posts	The Whitworth tap for Luger grip screws is not obsolete. There seems to be enough help provided to make a purchase, if not I will see if I can find my data for the right tap. But a little tip to help: If one side of frame hole is O.K. start the tap from that side and go through the mag well into the damaged side (after applying a drop of oil, of course) and re-thread the side needing straightened out. Slow and easy is a key. Jack

02-26-2017, 10:21 PM	#16
CAP Black User Join Date: Dec 2008 Location: Fairmont, WV Right here in Mountaineer country and God's country Posts: 767 Thanks: 100 Thanked 168 Times in 96 Posts	I got mine (Whitworth items) right here in West Virginia. They might still be in business. Jack

03-03-2017, 01:24 PM	#17
CAP Black User Join Date: Dec 2008 Location: Fairmont, WV Right here in Mountaineer country and God's country Posts: 767 Thanks: 100 Thanked 168 Times in 96 Posts	The Whitworth tap, etc. can be purchased at: Sabatelli Precision Grinding, 312 Sabatelli Drive, Mt. Clare, WV 26408. Phone: 304 622-8915. I don't recall the exact size of the threads or other specs of the opening in Luger grip screw holes. Jack

03-03-2017, 02:48 PM	#18
Zorba User Join Date: Feb 2013 Location: Merritt Island, Fl Posts: 951 Thanks: 776 Thanked 526 Times in 289 Posts	Ok, I'm confused. I thought Whitworth was a British thing. Why would the Germans use it? Obviously, there's some factoid I'm missing...

03-03-2017, 02:58 PM	#19
DonVoigt User Join Date: Apr 2015 Location: near Charlotte NC Posts: 4,678 Thanks: 1,441 Thanked 4,348 Times in 2,038 Posts	The first screw machines they bought were from the UK, at least that is what I read. Whitworth predates "standardized" metric pitches, IIRC. The luger screws and threads are a hybrid, metric diameters and TPI. Whitworth is a 55 degree angle thread, the current standard is 60 degrees, so depending on the use/tolerance/number of threads, a 30 TPI Whitworth will "fit"(close enough) a 30 TPI modern thread. Changing the gearing from TPI to metric is a bear and old "english system" lathes just won't do it. __________________ 03man(Don Voigt); Luger student and collector. Looking for DWM side plate: 69 ; Dreyse 1907 pistol K.S. Gendarmerie

03-03-2017, 02:59 PM	#20
CAP Black User Join Date: Dec 2008 Location: Fairmont, WV Right here in Mountaineer country and God's country Posts: 767 Thanks: 100 Thanked 168 Times in 96 Posts	Why would it matter to you? Do you want to know the history of industry in Europe from the 1700s? That would be a lot to learn. Many people that come up against this during current times have the same bewilderment. Let it go. Also read the thread above and get a portion of it. Jack Last edited by CAP Black; 03-03-2017 at 03:00 PM. Reason: add info.