Just curious if the heat treatment of steel, or some steels, results in the reddish color of the bued areas of some guns, usually receivers?

can be, or machining process, or alloy...
rugers are generally purple, due to cast material and hardness.

Your gun is "salt blued" common problem, you even see it on factory guns. Rust blue will turn out black..AND not turn after a few days..Salt blue is cheap..rust blue is not.

I used to own a "Blu-Blak" Lynx-Line salt-bluing franchise in central Kalifornia when I was young. I don't believe it is quite 100% accurate to say that the reddish blue is just because it is salt-blued.

I'd guess (without seeing it) that it was blued at the wrong temperature for the metal the reddish parts are made from. As a general rule, when a salt-bluer sees metal taking on a reddish cast, he should increase the salt-bath temperature by 5-7 degrees and let it "soak" longer than he normally would.

Typical of such rifles are Krag-Jorgensons, and with the Lynx-Line salts, I found that if you blued them at the normal temp (292 -0/+2 degrees, in a 2-hour soak) they would almost always come out with a reddish or even purple-ish cast. The same rifles, blued at 295-298 degrees for a 4-hour soak would come out very black indeed.

That's also why in my shop we used to blue certain parts separately from others where practical. From experience, we knew to blue certain parts at different temps because they were made from different kinds of steels. Sounds odd perhaps, but by doing them at different temps we could get them to come out the same colour as each other.

I have not blued with any of the salts generally used in the marketplace for the last 30 years, so can't comment about the current salts, but don't know why the chemistry would have been changed, if it has.

I have seen many old English rifles that the blue has turned a dark Cherry red over the years, I find it very pleasing if its not blotchy...

Also I think if the tanks are too hot you will sometimes get a reddish hue..

Some Greener GP Gun receivers have this almost purple blue colour. I also had a very early S & W Model 57 that had a almost "plum" barrel and cylinder.

I have a Sako L-461 action that is reddish from bluing.

The steels may exhibit a "bluish to straw" color from tempering in heat treat but IMO that has nothing to do with the resultand reddishness of the final blued product.

Further is is not evidence of poor metal or poor heat treat,.....rather a certain flaw in bluing.

I have had some of the receivers on my older Sakos and Rugers turn kind of a plum/purple. I can't imagine Sako going cheap on their blue; Ruger...perhaps. Lou

Casted receivers have inclusions of the silicone in them that will cause the purple or red haze, and at times are very difficult to get out, if at all.

Heat treated steel will always blue at a higher temperature than unheat treated steel.

Our elevation here is about 3400ft and I'll blue mild steel parts at about 275-280, and at times let them climb to 285, but no further.
Receivers that are heat treated with a barrel attached, should be dunked in at about 270 and stay in there until the temp gets to about 290-295 for most modern Remingtons or Winchester receivers. This won't hurt the mild steel, since it has already taken a good protective blue at the lower temperature.

Red can occur on forged steel or solid steel by putting your parts in at too high of a temperature, or not hot enough and not leaving them in long enough.
Most mild steels will take a good quality durable blue at 280-285 within 5-10 min. Anything after that, is for amusement only.

A barreled action can be in the salts for as much as 35-45 min. to let the salts get fully up to temperature for the reciever to blue.

When the temperature of your salts begin to reach 300, you run the risk of a burnt finish and a quick deteriation of your salts, if not ruined all together........To say nothing of its volatile nature when trying to cool it down, that could result in serious injury.

A reddish color is also common on CAST Winchester Model 94 receivers.

94's used castings on the post 64 production guns until the
switchover to the "Angle Eject" models.

Also the very first "Big Bore 94" rifles were forged
even though they had top eject. (these are pretty much collector items)

AD

A friend of mine swears that the base of his 7x57 barrel turned reddish after shooting about 100 rds on a hot summer day without allowing ANY time for cooling.

For those who are interested, here is a shop which does a variety of kinds of metal finishing for firearms.

I notice that they blue at the same temp my shop used to commonly use (292 degrees). They also do bluing of stainless steels (which some still mistakenly think is impossible...not so, but requires different salts).

May be useful info for those who would like a very short overview of how various finishes are produced (by this particular shop).

http://www.runniron.com/finishes/hot_salt.html

To view the different pages, just click the words relevant to what you want to know about, right at the start of their text.

I'd guess (without seeing it) that it was blued at the wrong temperature for the metal the reddish parts are made from. As a general rule, when a salt-bluer sees metal taking on a reddish cast, he should increase the salt-bath temperature by 5-7 degrees and let it "soak" longer than he normally would.

This has always been my understanding of 'red' bluing.....