Probably unsavable, but until you really know how deep the pitting is you can't be sure.
Take it apart, completely apart.
Scrub with brush and hot soapy water.
Rinse well.
The you have three choices for removing the rust.
-Use a chemical rest remover (lots of YouTube videos extolling one or another of these)
-Use an electrolytic process (again look on YouTube)
-Use steel wool or med sandpaper.
If the pitting isn't too deep and hasn't destroyed any internal parts then you can strip them down and re-blue them.
But the lever is lost, don't even bother with it unless as a test piece. Buy a new one of those.

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P.E. Metallurgy, consulting work welcomed

As Ed notes, the lever appears to be done; you need a replacement. You have to disassemble it, including removal of the barrel if possible. If the internal parts are OK, it is likely possible to salvage it. It's a matter of removing the rust from the receiver and seeing how deep. This will have to be sanded smoothe. Then it's a matter of polishing it. It's been 40 years since I've blued anything but with care you can end up with a lovely finish... just like a real gunsmith. I don't know what the processes are now.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

You can still buy bluing kits.
They aren't as fast or deep as they used to be, but they are safer to use.
Just remember that the first 4 steps are clean, clean, clean, and clean.
Anything on the surface will be more visible after bluing.

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P.E. Metallurgy, consulting work welcomed

With care, the blueing can be deep, dark and beautiful... I don't recall the products I used. My first project was for a No.1 MK.3 Lee Enfield. Used the full rifle the first year deer hunting, and for the next year, cut away all wood that wasn't needed. It was a WW1 rifle and the existing blueing was beautiful... made a sporting rifle out of it and even inlayed a diamond on the forearm and checkered the stock, and cut the magazine down flush with the 'trigger guard plate' and blued the receiver and parts... polished everything using tripoli (sp?). The stock was finished with about 10 coats of Varathane... I was 17 when I did this... Got my second deer the next season... first one a single shot at about 50 yards (I was a reasonably good shot), the second one about 7 or 8 shots... I had to re-load. My cousing still laughs about it... he said I put so much lead in the air he couldn't escape... only time I've had 'buck fever', one of shots was broadside at about 10'... and missed...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

The 336 is still being made and are relatively inexpensive, and not at all rare.

Step 1: take to a real gunsmith for an estimate

Step 2: provide that estimate to your insurance company

Step 3: collect payment from your insurer and buy a brand new 336

You have pitting. It will show through any bluing. You can try to belt sand through the pitting but I think you'll find it will remove an unreasonable amount of material.

If you want to improve the appearance of the gun but not keep it original, you could media blast the pieces, fill the pitting with a metal filled epoxy, and apply a non-translucent coating like Cerakote.

You may want to avoid Cerakote, though. People may think it's an assault rifle.

THANK YOU ALL for your comments and suggestions!!! Today I had a little bit of time to examine the gun more carefully. I did not have time to get very far into it ... yet, but I will! And I think the sooner the better because if I don't at least chemically neutralize the urine. It will progressively corrode the gun until I do. What I did find out today is that the parts inside the receiver still look operational. I have gotten most of the gun stripped down and I soaked those parts in a solution of 3% cleaning vinegar. I soaked these parts for 1/2 hour than scrubbed them with brush with Dawn dish detergent and Lysol then dropped them in boiling water with Lysol and cleaning enzymes. Then rinsed them with clean water. Blew them dry with compressed air. Than greased them with gun grease. I realize this cleaning process is doing nothing for the refinishing process. But I know that rat urine is VERY DANGEROUS and needs to be completely eliminated before anything else can be done. I will continue stripping and cleaning tomorrow. But as EdStainless stated. Its "probably unsaveble". As far as it looks currently. I think I have to agree. But I think his suggestion of the electrolytic process might be the way to go with this amount of corrosion. But it might not be economically feasible. It might be more advantageous to take the loss and take the suggestion that SwinnyGG said and turn in into my insurance company and purchase another 336. After all the scope is still ok. I could put it on another brand new 336! I will find out tomorrow. And I will send an update. Again, THANK YOU ALL!!!

You can get phosphoric acid at your hardware store. It's usually sold as concrete etcher.



Same product different labels.

Anyways, it's a bit simpler than the electrolysis method. Make sure you neutralize to prevent flash rust.

I suggest Shawn Woods on YouTube for dealing with rodents.

Well here is my update... Thank you 3DDave for your suggestion about Shawn Woods. I will watch his video after i'm done writing this update. Well, I was able to make time today to finish stripping down my 336. You guys are correct. The lever and the trigger are no good. They are both past any repair. And as far as the receiver and the corroded part of the barrel. I decided to take TugboatEng's suggestion and I saturated the receiver and the damaged part of the barrel with phosphoric acid. I realize its kind of overkill but I am going to let these part sit over night and see what they look like in the morning. I hate to be a pessimist. BETTER SAFE THAN REALLY SORRY! ( Anything involving firearms is ALWAYS safety first and foremost!). But I am 85% convinced there is no hope for this rifle. By the time I remove enough material to get past all of the pitting and corrosion. I believe the receiver will not be thick enough to take the chamber pressure of the cartridge being fired. And I know me. No matter what I would have done to the rifle to have it repaired. (If that is even possible). I would never again be able to trust firing this rifle. I would ALWAYS be worried about the receiver exploding in my face. And I am sure a .30-30 Win. cartridge can do some real damage! Its simply not worth it. I have come to the conclusion . I am just going to turn it in to my insurance company. And buy a new one. One more thing... I AM going to catch that RAT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Would be great if you posted a photo of the dead rat

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

I will post a photo of that DEAD RAT when I catch him!!!!!!!!!!!!!!!

Do the number of ! equal the number of shots you've already let off at the said animal?? And missed.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

I DON'T miss

Bullets are another well known degradation mechanism…

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

brimstoner, I am not sure what you meant in your last post. ?????? But I never said I was going to shoot that rat anyway. I simply stated, "I AM going to catch that RAT" !! So, tell me, why are bullets a degradation mechanism"?

I meant bullets are a degradation mechanism for rodents.
I was responding to littleinch, not intending to incite a disproportionately violent response to your uninvited house guest. However you do it, I hope you are able to deal with the varmint.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

If you are referring to the corrosion inside of a gun barrel caused by firing a bullet or bullets. Is'ent that why manufacturer's recommendations tell us to clean each firearm after each use? To prevent corrosion? (Or at least slow it down) And even if not. It sure would take A LOT of bullets fired to create the kind of corrosion that rat urine caused! In that amount of time. That rifle sat in storage LESS THAN 3 MONTHS!! Actually, I took it out of storage to give it a storage grease treatment. Like I do about every 3 months or so. When I stored it. It was in pristine condition. I can't imagine bullet corrosion working that fast ! I mean if we are going to get down to technicalities. Steel in any average environment is susceptible to its own degradation mechanisms.

Brimstoner, please understand I was not trying to be a wise guy or anything of that sort. I am ALWAYS interested in what Engineers have to say! I guess I just wanted you to elaborate. I apologize! I should have just said that.

And YES!!! I also hope I can put a stop to this vermin before it becomes an infestation!!! If it is'ent already! I've set traps and done everything possible to catch this rodent. But I have got to tell you. THIS RAT IS SMART!!! So far he has avoided all of the traps and i've baited them with peanut butter. He has not gone anywhere near them. That I can tell. And get this ... I HAVE A CAT!! Obviously, hes worthless! Hes fired!

If I don't catch this rat in another 5 days. I am going to bring in a professional. Before its to late.

How much have you used Shawn Woods' examples?

Well i made the 5 gal bucket trap. 2 of them and baited it again with peanut butter. No luck. And I did not get the traps that Woods recommends only because I already had some old spring loaded traps. I was thinking about that Uhlick repeater. I was going to make one now that I see the old spring traps are not working. Thats why I said if I can't catch him within 5 days I was going to call in a pro. I figure I can make 1 within a few days and give it a few days to catch him. If the Repeater did not catch him. Then I will call in a pro.

Have you tried a UV light to see the urine tracks to see where the rat is going? There are other baits besides peanut butter - maybe your rat has already learned to stay away from that.

The rat is obviously attracted to guns. Perhaps you should bait your trap with a Hi-Point or another low value firearm.

Also add a trail camera to see what the rat is doing. You have one. Perhaps there are more.

Yes, I am hooking up my trail camera today and the UV light completely slipped my mind. But I DO have a UV light I will use it today. The worst part is. When there is 1 rat you can almost bet there are more. And I am absolutely going to try a different bait. Obviously this rat is clued in on the peanut butter. I was thinking to change the bait on the trap without setting the spring on the trap for a day . And let the rat get comfortable with going on to the trap to get the new bait . Then after he is comfortable. Set the trap. As far as the new bait I was thinking smoked bacon. I know one thing for sure , without question... My cat is fired!! He is worthless. I assume that if I slept 18 hours a day like my cat does. I would be worthless to. But this is no excuse! This cat is going to a different owner. I know of a elderly lady that would like to have him. She certainly can have him. But not until AFTER this rat problem is remedied

You've got a bunch of folks here getting really emotionally and technologically invested in rodent extermination!
Please don't fail us!

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

If you set out spring traps, make sure that they are nailed down.
I have had to follow the trail of blood and then dig the dead rat out from behind a cabinet.
Not fun.

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P.E. Metallurgy, consulting work welcomed

Yes Sir... I will not fail you!!! I don't have the traps nailed down. But, I do have them screwed down to a long strip of plywood. So if and when he does snap 1 of the traps. He is not going anywhere. I am now preparing to install my trail cam. But I will first use my UV lamp to see exactly where I should place it. Currently I have the traps set up against the wall in the backside of my kitchen. That's one of his routes. Of course I could tell because of the feces trail. I will send an update later on today

Well guys, I changed the bait to smoked bacon!! And nothing yet. I have not seen him on my cameras at all either. And no new urine trails. I am not giving up!! I can't imagine he would just move out. Believe me ... I AM NOT GIVING UP UNTIL HE IS CAUGHT!!

Only one option. Buy a new gun and offer that as bait.

Well 3DDave thanks for that strange suggestion but thats not going to happen! But I will give you the latest update. My waist-of-skin cat FINALLY DID HIS JOB!! YAY! HE CAUGHT THAT RASCAL! I thought ... Jes why is this cat not catching this rat. I thought that was the natural order of the species. Well guys, If you think about it.. It was not the cat's fault at all!! It was mine!!! I was thinking, wow, why is this cat not interested in catching this rat?? This is one LAZY cat!! Then it dawned on me... Hes not lazy hes full! I was feeding him to good! I cut back on his meals and the amounts of his meals. And would'ent you know it! He went to work! He brought me that darn rat. And it was in pieces! He tore it up! And he was so proud of it he deposited right up on my bed!! I know I said I would take some pictures of it . But I am not going to do that because the shots I took are disgusting. I am not going to be relieved just yet! Not until I KNOW there are no other rats! It is VERY RARE THERE IS JUST ONE. I am relatively sure if there was 1 there are more. So I will keep my trail cams up and running for a few weeks just for good measure. Rats can do some REAL DAMAGE! And it does not take very long ! And it can be VERY EXPENSIVE!

Keep starving the cat and more rats will end up in your bed.
Every time the cat brings you a rat, you give it a treat.

Soon enough you will have a cat that is a bonafide bounty hunter...

Regarding Shawn Woods for a time I was watching his videos at night or on weekends. My wife never understood why as we live in a high floor apartment in a city.

I almost wished we had a rat problem, just to try some of Shawn's traps...

Yes, I agree with you MedicineEng, Shawn Woods has developed some pretty clever tricks!! If I have learned anything from this experience. It is that I am truly amazed at how intelligent rats are. But it makes sense! They could not have survived over eons of time without learning some technics for survival. (Bonafide bounty hunter LOL LOL YES THATS FUNNY!) Then I would have to change my cat's name to ... Dog, the Bounty Hunter!

Wouldn't happen in Alberta. Plenty of rifles but no rats! We've have rat patrols at the border since 1950.

Contract Tom! Get a good mouse trap, put an giant outdoor next to the gun saying "it is expressly forbidden for rats to camp, to defecate and urinate on my rifle" if you still believe in humanity, please convene the UN security council to make a motion of censure against shameless and indecent mice.

regards