case colors streak

[Dean Romig]

Every once in a while we will see a recased gun with it but they are few and far between. And I wonder, in a refinished gun, if that stripe isn’t more of a welcome but unexpected result than intentional.





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[John Bastiani]

Originally Posted by Dean Romig

Every once in a while we will see a recased gun with it but they are few and far between. And I wonder, in a refinished gun, if that stripe isn’t more of a welcome but unexpected result than intentional.





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Forgot to ask if the streak is also present on the late Remington guns?

[B. Dudley]

Originally Posted by Dean Romig

Every once in a while we will see a recased gun with it but they are few and far between. And I wonder, in a refinished gun, if that stripe isn’t more of a welcome but unexpected result than intentional.





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Odd... as I recall, nearly every parker I have had re-cased has had it.

Yes, it is dependent on the case hardening process. But more a function of how the trigger plate is machined. The channel in the plate for the unhooking slide results in a dramatically different thickenss of material up the middle of the plate. This is really the main reason for a difference in the appearance and patterning of the colors in that area.

And I will add that not all original examples are that pronounced. Every gun is different.

[Dean Romig]

Originally Posted by Brian Dudley

The channel in the plate for the unhooking slide results in a dramatically different thickenss of material up the middle of the plate. This is really the main reason for a difference in the appearance and patterning of the colors in that area.

True Brian, and the variation in thickness of the plate where that channel is machined results in the variation in temperature across the width of the plate I made reference to.

As I recall, you send your case coloring work to DTR and they are expert in the various case colors of the various gun makers of old.

Dave Trevallion showed me his 20 gauge Trojan he had restored himself and sent it to Doug to color case harden. I honestly believed it was a very high condition original, stripe on the floor plate and all. David told me that Doug had done it fifteen or more years earlier. I was really surprised but shouldn’t have been, knowing the accuracy of Doug’s work.





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[John Bastiani]

Well I guess I can throw the streak theory out the door in determining if the case is original since some of the re-blued guns have this streak as well. I also noticed that the GHE-28 gauge for sale in pictures #43-46 and 47 show the streak on the floorplate and had me thinking that the case was original on this gun but since re-cased guns could also have this I remain skeptical.

[edgarspencer]

Originally Posted by Brian Dudley

Odd... as I recall, nearly every parker I have had re-cased has had it.

Yes, it is dependent on the case hardening process. But more a function of how the trigger plate is machined. The channel in the plate for the unhooking slide results in a dramatically different thickenss of material up the middle of the plate. This is really the main reason for a difference in the appearance and patterning of the colors in that area.

And I will add that not all original examples are that pronounced. Every gun is different.

Brian is correct in that the inside of the floorplate is machined such that there are three areas of mass; the outside two the same and the center, much thinner. See my work of art below.

The outside square represents the packing box. Surrounding the part is the packing media, which is an organic mixture of the makers own recipe. The drawing shows a theoretical cross section.

There are three factors involved: Random, Variable, and Fixed.
The Fixed factor is the part being heat treated.
The variable factors are Time and Temperature
The Random factor, almost entirely human, is the location of the part, in relation to the inside walls of the packing box, location of any other parts also in the box, and the density of the packing material.

The entire part is held sufficiently long enough for the core of all sections to reach the same temperature.
The quench process is where the magic occurs because the three areas of mass are cooling (from the center outwards) and while the quench media is still working at cooling A & C, B has gotten as low as the quench media will allow. Everything started at the same temperature, was ultimately soaked at the same temp, and eventually back down to the same temp. However, the rates at which they rose, and cooled was controlled by their mass.

[Mike of the Mountain]

Originally Posted by Brian Dudley

Odd... as I recall, nearly every parker I have had re-cased has had it.

Yes, it is dependent on the case hardening process. But more a function of how the trigger plate is machined. The channel in the plate for the unhooking slide results in a dramatically different thickenss of material up the middle of the plate. This is really the main reason for a difference in the appearance and patterning of the colors in that area.

And I will add that not all original examples are that pronounced. Every gun is different.

Good call Brian. Makes sense that any difference in metal thickness would cause temperature fluctuations.