What's up with the nose?

[Newbflat]

I need a quick bit of educating. I keep seeing WWII vintage pistols ( maybe others?) with what looks like the nose ( first 2 inches?) has a different finish than the rest of the gun. A very good example of then is the nice gun in the recent posting here titled "Dads 1911A1"..... I would love me some educating!! ??

[Hawkmoon]

You are referring to the muzzle end of the slide looking darker than the rest? That's a visual confirmation of the fact that the military M1911 and M1911A1 slides were not fully heat treated, they were heat treated at the muzzle and around the slide stop notch. The depth of the blueing is different because the harder metal reacts differently to the blueing process.

Be sure to read the sticky thread "Should I shoot my old M1911?"

[Newbflat]

Well hot diggity dog if that doesn't make a whole lot a sense! .... that is why i come here. Thanks Hawkmoon.

[John Holbrook]

Here is an example of a 1942 Colt showing the temper line. They had not started tempering the slide stop cutout yet..

http://www.fototime.com/%7B459A5431-C826-410C-B6B7-775D8783EFD7%7D/picture.JPG

And here is a 1945 example..

http://www.fototime.com/%7B4333712D-ABE6-4641-91B5-B7DA989A963F%7D/picture.JPG

[Hawkmoon]

John, may we link those photos into the sticky thread discussing why not to shoot the collectables? Those are some of the clearest photos of the heat treat line I have ever seen.

[John Holbrook]

Sure and I have lots more if you need them. In fact you have my blanket permission to use any photo that I post... When I get back to the house, I will post some of the heat treat around the slide stop notch.

John

[Newbflat]

So when did they start heat treating the slide stop , and when the whole slide? Just curious but does anyone out there know the rockwell hardness is in the different tempered zones? Was this done to commercial models at the same time?

[John Holbrook]

I believe it was in 1943. ALL US&S pistols have it, and I will post some photos later. I know that Remington Rand experimented with treating the whole slide, however they gave up when they could not control warping of the slide. Colt finally figured it out after the war and the post war slides are HARD and will ring like a bell.

Many RR slides will have Rockwell punch marks on the starboard side of the slide. Usually one on each side of the heat treat line.

I believe the Rockwell treat was C 60.

[Newbflat]

Thanks for the info.. Im beginning to think of you as a large 1911 shaped encyclopedia with arms and legs.

Just one thought, C 60 is VERY hard. Hard enough that if you dropped the slide it i might brake in half. This is cutlery steel hardness and very brittle. I would have expected the mid 40's..... But what do i know.

[John Holbrook]

Here are four slides that show the heat treat of the slide stop notch..

http://www.fototime.com/%7B2FEE1DD9-6016-4CD3-8D01-46249C60F538%7D/picture.JPG

http://www.fototime.com/%7BA7553EF1-7F3B-4D31-BBFE-5076E272805F%7D/picture.JPG


http://www.fototime.com/%7B55586EA3-6B9C-4DCA-A5F3-86E3D01008D4%7D/picture.JPG

http://www.fototime.com/%7B26BBF3D2-0ADA-4394-AB7D-87B74734F9F0%7D/picture.JPG

[John Holbrook]

Here is an Ithaca slide showing the Rockwell test punch marks around the slide stop cut and forward on the slide for the front.

http://www.fototime.com/%7B93CA42E6-E93A-45F3-93A7-9AFA280C09DB%7D/picture.JPG

[wjkuleck]

I have Argentine Modelo 1927s with the characteristic heat-treated-notch discoloration.

Regards,

Walt

[wjkuleck]

I have Argentine Modelo 1927s with the characteristic heat-treated-notch discoloration.

Regards,

Walt

[John Holbrook]

Another Colt showing the heat treat slide.

Also note that this pistol has a stamped trigger, however the early eared hammer and slide stop.

http://www.fototime.com/%7BB37699D9-70CD-4C6C-8D12-D9016EC094F4%7D/picture.JPG

http://www.fototime.com/%7B79DA00E3-498A-4917-BA22-ABBCCC5D7E86%7D/picture.JPG

[John Holbrook]

Another Colt..

http://www.fototime.com/%7B8D26D8DB-D743-4C15-8AAB-9F6C55F6FA6D%7D/picture.JPG

http://www.fototime.com/%7B87A12FD0-2861-4BE3-AC79-3F1B682C1714%7D/picture.JPG