Bluing cast RB breech block?

[texassako]

I decided to take on the challenge of fitting an aftermarket centerfire breech block to my #2 rolling block and it is just about ready to be finished. The old one was blued and the hammer is blued, but I am not sure what the best DIY method is to blue a cast part. All I have found so far is Oxpho-Blue should work and hot blues usually turn cast parts red or purple instead of blue.

[oldred]

I did an old Stevens shotgun cast frame with Mark-Lee Express rust blue and turned out exceptionally nice, I have been told that most rust blue methods work quite well with castings. Any kind of cold bluing is not really bluing at all and none will have any real wear abilities, some may be better than others but all are only thin layers that fade in a short time if handled very much. Rust blue is easy to do at home, safe and easy requiring only a container to boil water in and maybe a heat gun or even a hair drier to preheat the part and the result is one of the most durable/attractive finishes you can achieve.

[22cf45]

Oldred has given you excellent advice.
Phil

[texassako]

Thanks for the suggestion and confirmation. It is going on my next order.

[Reg]

A lot of these cast replacement parts seem to have been cast from 8620 steel, a good strong easy working steel. If so, it should respond well to about any bluing process.

[johnson1942]

this is what i do for parts that fit in my stoves oven. i use Mark Lee express blue available from brownells. i put the part in a clean oven safe glass pie plate. have the oven temp to 300 instead of 200 like it recommends. i find 300 degrees is fool proof, 200 gives iffy results for me. make sure you breech block is smooth, clean and totally grease free. thats a given on all types of blueing. put in pie plate and heat to 300 degrees. take out plate with mitts and put on top of stove and with a saturated rolled up pure cotton swab swab the part completely. i turn the part on the plate with a kitchen wooden tongs. looks like a big wooden tweezer. i dont even card. back in oven and repeat 8 to 10 times. now when your close to the 10th time have a pot of water boiling on the stove with about 1/2 teaspoon of backing soda in it. the last time you take it out of the oven put it in the water and boil for 30 min. the bakeing soda will stop the blueing action. the boiling will set the color in real good and take off the excess. i find this method just as good as any hot blueing i have done by someone sent away. you can also use mark lees express brown. when you boil the express brown it will turn a deep beautiful black. i prefer the black look and i usually bead blast all my parts for a deep dark matte finish. when you take the parts out of the boiling water keep oiling them down for a while. also some thing else that works well is furniture paste wax put on the steel instead of oil, especially if it is a matte finish. it will also water proof your steel for a long long time. this method is very proffesional looking and lasts as long or longer than hot blueing. good luck what ever you do.

[oldred]

That method sounds interesting, I have never heard of skipping the carding step between applications but the next time I use rust blue I'm going to give that a try!

[johnson1942]

old red i cant tell you if that would work on rust blue but on the mark lee blueing it works. if you go up on the rimfire spot on cast bullets you can see the gun i just did by this method. its under the restoring a old 30 dollar barn gun. i really like the mark lee. i rust blued a leaded steel barrel from the oregon barrel co cause it wouldnt fit in my oven. i did it over about two weeks. with that type of steel it didnt turn out a modern blue but looked very antique. at first i was disappointed with it but then as i got to looking at it it really fit the gun. it was a custom 1840/s type plains rifle in .50 cal. now it is one of my favorites. i boil all my barrels even if they are rust blued. i got a thick piece of 3 inch pvc pipe and capped it, it is 48 inches long. i fill it with boilng water and it really holds the heat in the water. i seal a baggy over the top after i put the rifle barrel in it and leave the barrel their for at leaste an hour. it really sets the color into the steel.
i think limited funds and liveing really remote has made me figure out a lot of things for my self.

[oldred]

Mark Lee Express Blue is what I use and so far it has given exceptional results on everything except a 4140HT steel receiver. Never did for sure figure out the problem with that one but the metal seemed somewhat rust resistant so I suppose that alloy is just not the best candidate for that particular product. Even when I sanded/repolished it and hot blued it I still ran into problems that were only solved by experimenting with temperatures and time in the solution but all that is another story. I do both hot blue and some rust blue (with the Mark Lee product) and I have found the rust blue to be even more durable than the hot blue, finished appearances differ somewhat but both are equally nice and the rust blue is right up there with even the best finishes!

[johnson1942]

. old red i think you have taught this old boy something, i didnt know mark lee was a rust blue, well now i can say im rust blueing and yes i agree with you, i really like that product and i think it is better than sending the pieces away to hot blue. the rust blue i used was a slow wipe down process that took a long time and if i had a oven that would have taken a 36 inch barrel i would have used the mark lee. once i got low on both the rust blue and the rust brown from mark lee and i combined them and together they gave a very dark nice color. i dont want to use a propane torch on a barrel because a famous muzzle loader builder and for the life of me i cant think of his name told me once this. he said i started to heat a longrifle barrel with a torch and it made a right turn right in the middle. had to throw it in the garbage. i dont want to risk it. any thing that fits in a oven and heats evenly i do though. thanks again for the info

[oldred]

I have been a welder and metal worker my entire working life and I am very familiar with metal warping, I would never ever heat a barrel with a torch for the very reason you mention! If someone thinks this is a lot of worry over nothing just place a piece of pipe about barrel length in a vise held near the end and start heating on it with a torch, if you run that torch up and down the length and watch the end you can actually see it move!

[johnson1942]

old red i was a steamfitter before i became a registered nurse. what your talking about and i bet you know already is coefficient of linear expansion. had to figure a lot of math problems when i went through the apprenticeship about just that. when i heard the gun builder say he put the torch on one side of the barrel i knew he would be in trouble. a barrel has to be heated evenly or it will bend. i always see that it states on the rust blue produces that to heat with a torch or heating gun. the torch part should be explained a little better. soft flame and keep the torch moving constantly. still it is too risky. i just measured my oven and a 30 inch barrel will fit in it. im building a new gun so i can rust blue the barrel in my oven and get it done the way i want and save about 100 dollars in doing it my self. i checked the internet also and their are a lot of guys doing the same thing out their and their pictures shows really good results.

[Hooker53]

Texassako, when you fitted your breech blank, how did you work out your Extractor cam? My casting came with that area missing and looks like it had been turned thinner in that area and bead blasted. Now understand I have not seen a CF breech block so if another part goes there, that's what I'm trying to fiind out. Either way with mine, I will have to make a waffer washer with an Extractor cam cut into it and held in place by the firiing pin screw which on my casting will turn out having to be a barrel screw. Much bigger than the RF firing pin, retaining pin. Thanks.

[texassako]

I used a thinned, modified generic washer with a slot similar to the one on the RF block so I could reuse the old extractor. The fat firing pin plug keeps it from rotating. I did not find a reason to permanently attach it to the block. I can get a picture up later, but it is functional rather than pretty.

[Hooker53]

That's the only way I see it could work with a washer affair like you are talking. I would love a photo or two. Did you go with the casted size channel for the firing pin or drill it out bigger? Sure want to thank you for your Info.

[johnson1942]

mark lee express rust blue.make a scratch free surface, then bead blast it. put in oven at 250 on a glass pie plate. heat, then cover with mark lee rust blue 2 times. then wash clean with water, and repeat process 6 times. when done boil in water with bakeing soda in it for one half hour. take out of boiling water wash clean and dry and oil very well. wipe clean later than wax with a good floor wax. just done a barrel and a butt plate yesterday and they turned out beautiful. if you like black better than blue than do with marklee rust brown first then repeat process with the rust blue. you will love the results. if I use a ruffer matte finish and the beads are gritty I may spray the parts with a car spray enamel clear of course. ive done that to trigger guards and buttplates. spray it on when the blued parts are clean and dry. lightly misting them a couple of coats.