Restoring an old Fusil Gras mle 1874

So, I have this old rifle, and I want to get it cleaned up a little bit. The rust on the exterior is nasty, but I want to keep some of the patina. The bolt has the nastiest grease I've ever seen, and the barrel looks like it was caked with mud and garbage. Its obviously been modified at some point in its life, as its missing about half of the barrel, as well as the stock that would have gone under it. The cleaning rod is nowhere to be found, probably discarded with the barrel. I dont really want to get it perfect, but it would be nice to shoot it some day.
I'm new to this whole milsurp/ restoration thing so any help would be greatly appreciated!

Removing grease first will be helpful and then using an electro rust removal could help. That returns you to a basic rust free carcass to start on. The wood might need a liquid strip to clean it... We have whole threads about that here... You'll have a hard time keeping a patina while removing the rest.

Pictures would help the experts on this forum to give good advice. Many pictures will get you lots of advice.

Pics would help...

Alright, here are some pictures of the bolt + firing pin, the outside of the barrel, as well as the rest of the gun. If I missed anything let me know. Kinda hard to take a picture of the inside of the barrel, so I cant really show that.

Don't know how you'll keep any patina and remove the rust blisters...

Well, like I said, Im pretty new to this whole thing, so I dont really have a great understanding of restoration. At this point I just want to get this thing into decent condition, mainly just cleaning up the old grease and removing some of the rust. I really appreciate y'alls patience with me.

https://www.youtube.com/watch?v=mXj_...i2HAV&index=61

The excellent Mark Novak provides a wealth of knowledge. For what it's worth, I boiled out my rusted No.5 Mk1 Enfield and was very pleased with the results.

When the Gras was surplus they saw everything imaginable. Bar stool legs, lamps, some were modified to carbines and in some cases shot guns.
on the left side of the receiver there should be a makers mark. It will say Maunfacture de arms and then a name. could you let us know who that was?
as far as the wood goes, it's original finish was gone years ago. At this point clean, sand and give it a light coat of boiled linseed oil or Balistol, which ever is your preference.
Using brass brushes or bronze wool can knock off the worse of the rust (not use steel wool or a wire wheel. Ever.) after that I would recommend you boil it and then see what you get after that.
11mm gras is available for a princely sum but reloading for it makes it much cheaper in the long run.

I'll second the Mark Novak series.

Educational AND entertaining!

Hard to tell from the photos if this will work with your barrel but you can give it a try.

The first attempt to remove rust I use is scraping it off. Some guys insist on using softer metals like an old penny. I generally use the flat back of an old pocketknife blade. Yes it's steel which is as hard as the barrel and the potential is there for scratching but I've never had much issue with that. The edge is not sharp, it's slightly rounded and basically crushes the rust off. It does not harm the finish where their is no rust and where there is rust, it usually leaves an appearance very similar to the unrusted areas. I have a lot of posts on here with before and after photos so you can see how they turned out. This only really works if the metal is not pitted or at least not pitted much or deep. It's time consuming and labor intensive but it is also very satisfying watching the steel come back to life.

If pitted, I go to method two which is electrolysis. They say this does not remove the existing finish but in my experience it does to a degree at least. Another method I used because I did not have access to an electrolysis set up (they aren't super expensive, about $40-$50) is soaking it in white vinegar. This removes everything to bright metal with the exception of deep pitting in which it turns the orange rust to a more stable black rust. I don't use this method anymore with the exception of small parts. But in your case with the rifles value already gone so originality is no longer important, you could to this with the intention of re-bluing afterwards.