Home Forums Hunting & Shooting Gunsmithing Metal Prep for Rust Bluing

As a follow-up to the rust bluing thread, can somebody post a quick tutorial on metal prep. I have a 1903 Springfield and 96 Mauser project I'd like to rust blue and any pointers on metal prep and techniques for keeping the lines and edges on these receivers crisp (especially the 1903) are really appreciated. I've seen a lot of reblued 1903 Springfields that were heavily polished and had their lines heavily buffed down, which really detracted from their classic good looks. Many thanks.

1. Stay away from buffing wheels.
2. Completely disassemble the rifle and degrease throughly.
3. Remove all rust and blue with a 50-50 solution of muriatic acid and water. You can get the acid at any hardware store.
Use proper procautions in handling the acid. Dipping parts is easiest, but you will likely have to swab the solution on the barreled receiver because of it's size. Apply the solution until all the rust and blue disappears. Probably no more than 30 sec. Have a bucket of baking soda and water solution ready to apply to the metal as soon as you finish the acid treatment. This will kill the acid. Blow off all the solution you can and coat everything with WD-40.
4. Now you are ready to polish. Draw file any pits out as needed
Start with 180 grit ALOX paper or cloth. Use wooden or hard rubber blocks, dowels bars, etc. to back the abrasive and go over everything. You can use the shoeshine technique on round surfaces. Remove all the machining marks, scratches, etc.
5. Jump to 240 grit and repeat going 90 deg to the direction you went on each part with the 180. Remove all the 180 marks.
6. Jump to 320 grit and polish in the original direction,90 deg from the 240 grit marks. Remove all 240 grit marks and finish up with all visible polishing going lengthwise the barrel and action, using worn 320 paper or cloth.
7. This is as far as you need to go for slow rust bluing. Some people will disagree and state that you can get a higher polish blue by going to 400 or 600 grit. If you do, you are wasting your time and sand paper. The only way to get a high gloss blue is to polish the metal to the finish desired and then blue in the standard hot salts blue used by most gunsmiths.

RAN

I'm one of those who would disagree. My advice would be to do a test piece of steel. Polish one side to 320x and take the other side down to 600x, and rust blue the thing, and decide for yourself how you want your gun to look.

Interesting. The last one I did I wanted to have the receiver more matte than the barrel, similar to the finish on pre 64 Model 70s.

I polished the receiver to 280 and the barrel to 400. When the job was done I couldn't tell the difference. Next time I may let the receiver rust for a longer time with a stronger solution, and the barrel for a shorter time with a weaker solution

Not a lot of difference between 280 and 400x. I would have expected the results to look similar. Also, abrasives differ somewhat between makers. One man's 320 could be another man's 400, etc.

Thanks all for your input. I'm trying to close on my first house and hope to set up a shop in the two car garage by this summer. I have noticed the finishes on pre-64 Model 70 receivers and wondered how they were done. It almost looks like they were prepped with a very fine abrasive after polishing - but this is just my own "wild arse guess."

I'm probably just wasting my time but I took it to 2000+ just to see how it will look. I'm hoping for WOW!!!!!!

I think a glass bead job on the receiver and a high polish on the barrel might do it.

I was thinking the same thing. Possibly a soda blast instead of bead blast?

Thanks again. Does anybody do anything with the interior of a bolt action other than remove existing finish and reblue?

I don't. And as a matter of fact, you can rust blue right on top of an existing hot blue job.

Polishing it the art of rust bluing. Anyone can blue a piece of steel, though there is some skill in getting rust blue to a fairly high luster. The polishing, however is everything.

How do do it, depends on what it is. Many folks bluing a round barrel will chuck it in a lathe and have at it. Done wrong, looking at a low angle along the barrel will show waves in the finish after it is blued. If done right, reflected straight lines down the barrel will be appear straight. And there will be no waves.

I always polish my barrels, round or octagon, on the bench by hand, and work with hardwood backers or pieces of steel behind every piece of paper. (hard maple is ideal and won't mar the work if you slip - as a piece of steel will). Barrel polishing in this fashion is all unidirectional, but that's okay. Just takes longer in my experience. I often find that as I work along, I have to back up a grit or two because I didn't get a scratch from a courser grit completely polished out, but could not see that until I had gone on with finer grits. Check frequently by looking at the barrel at low angles with light out in front of you (a northern window is just about ideal for most lighting for this sort of thing).

When polishing I usually use WD40 for a lubricant. However, with courser grits something like Automatic Transmission Fluid works well too. But once you get to the finer grits, water is the only way to go in my experience ATF will basically prevent finer grits from cutting much of anything, and even WD40 will slow down the process.

Do not be cheap on abrasive papers. Change often, your fingers will thank you.


Polishing actions is another matter entirely. Switching the direction of the polishing by 90 degrees between different grades of abrasive is great. But be sure that the final grit, no matter how fine, is in line with the bore.

The problem with actions are all the strange angles, blind corners, concave and convex surfaces. Each action requires a unique sequence for polishing it best. How you go about requires experience, but each corner and line should be knife-edge sharp if possible and each blind corner needs to be polished all the way to where it meets the next surface. I have a photo or two that illustrates some of these problems but can't upload at the moment, unfortunately.

Some other things that help is to have a secondary set of screws if you are polishing parts that will mated together (e.g., the lower trigger bar and tang on an 85 Winchester. Another very helpful item is an old barrel stub to screw on to your action so you can hold it in a vice clamp easily. Holding the action well, is a big help in making polishing easy and relatively painless.

IF YOU USE YOUR FINAL BARREL WHILE POLISHING THE ACTION YOU WILL REGRET IT. The caps are there for a reason

As said, I have a Mauser 96 and 1903 Springfield action. I figured I'd start with the 96 as it is far less complicated than the 1903. Many thanks to all again.

Here are a few pictures of a Winchester being polished out. I don't know what grit had been done when these photos were taken but it has a good long ways to go.

The lines here are pretty crisp and nowhere on this action is anything polished with fingers behind the abrasive. Every surface is polished with hard-backed paper.

Doing the various surfaces in a specific order makes it easier to keep the edges sharp. Generally I do the concave parts first, then the lower flat surfaces, then the convex top, and finally the raised sides at the front and back of the action (these two surfaces are done at one time to keep them perfectly in line with each other. You can see that there are many surfaces and edges that have to be maintained and clearly defined.




The final product is the top rifle here. The barrel is rust blued to a pretty decent luster, not glossy. The action was later engraved, case colored and then the colors were partially removed

I've come to the conclusion that this sort of thing is best done by people with OCD rather than people like myself with AADD. LOL


(no offense to anyone)

Not sure what OCD is, but I probably border on AADD. I just flip on a football game in the shop and have at it until I'm tired of it. Then I do something else for a while.

Rust bluing is one thing that the average guy can do well, with practice - really well. Wood finishing is another and it is similar.

OCD=Obsessive Compulsive Disorder

I have never rust blued anything, but I have read a little about it. Seems like I have read that etching it with a mild acid after polishing is supposed to be beneficial.

Beneficial in that it gives the bluing solution something to bite into.

Anyone have any ideas about this?

The rusting solution IS an acid and does the etching. What you are reading about is that some folks feel the need to etch faster at first because polished steel is slow to develop rust at first (for this reason alone a well polished barrel is superior to a "matte" barrel, in my opinion).

The lack of patience and a clear understanding of what is happening causes folks to try shortcuts like this. They work to a point, but they will not produce the finer finishes that are, again in my opinion, far more desirable.

I use very dilute solutions for rusting, even with the first coat. This violates some folks Rule #1. But I desire that fine finish, not the course stuff that some folks thing is somehow "better".

I also reapply over an over on a barrel for each coat, esp. the first (another rule violation). Multiple applications help with evenness. And, in the first application they should be very light - that is, there should be very little acid on the applicator. A small patch of worn t-shirt that is dampened and then rung out as dry as possible is almost too wet. If you have to much fluid in any single pass over the steel, early in the application process, you will see the fluid bead up on the surface. For a quick example, take a wet paper towel to you window and see what happens. Same thing happens on your clean, polished barrel.

I also like to apply the solution to the barrel when it is hot from the boiling tank. This helps dry the acid evenly over the barrel (avoiding the beading) and then humidity will work more evenly with the dried solution to produce the rust you want.

These are some great discussions. I've learned a lot.