Most of the time I'm lucky and can get ammo like this for my various older pieces that is non corrosive. Unfortunately, you need to check what you buy as most surplus ammo IS corrosive. On cleaning weapons fired with corrosive ammunition, it's the salts used in the primers that is the actual culprit. It made them fairly stable and surefire, but left behind a salt residue that is hygroscopic. Naturally, that attracts moisture and holds it, so 'corrosive' to steel, for when salt combines with moisture damage starts to occur to the metal surfaces. Not much different than dipping a carbon steel tool in the ocean.
Oils or petroleum based products will not break down the corrosive salts and therefore are ineffective in cleaning or neutralizing the salt compounds. Most chemists will agree that modern bore solvents will not break down the salts. Alkaline based solvents will break down the salts, as well as simple soap and water or just plain water. Straight Ammonia will not break down the corrosive salts and can cause damage to the bore if left in too long. It may also remove metal deposits such as copper from the bore The best 'solution', no pun intended, is water. It dissolves the salts and washes them away.
There are as many ways to clean your weapons, and with what products, as there are shooters. I'm not a professional, or a gunsmith. This is just what has worked for me.
If you have some on hand -Ballistol is a water soluble cleaner originally designed for military use with corrosive primed ammunition.
Cut 3/1 of water to Ballistol, and it makes a fine bore cleaning solution. Used straight, it's a good lube and protectant. When the water in the solution evaporates, it leaves behind a protective coating.
There's also the tried and true Hoppes #9. Hoppe's is one of the few solvents that is old enough to be designed to neutralize the corrosive salts formed by corrosive primers. But what if you don't have anything like that on hand?
Some folks have tried to make their own ammonia and water based concoction to clean the bolt, bore, and any other effected areas, but frankly, an ammonia based window cleaner will work as well or better.
The point behind using Windex is twofold. The surfactant in the cleaning solution helps the water maintain contact with the salts and dissolve them, and the ammonia in the cleaner attacks the copper jacket fouling and dissolves it into a mass of 'blue goo' (picture Smurf hit by phaser set on liquidate). It's also cheaper than dirt, compared to premium rifle cleaning solution. You can even get more cheap by using a generic version of Windex, or other similar "blue" cleaners that are on sale. The spray bottle makes the perfect applicator, and if you use this stuff for household cleaning you can buy a big jug to refill the more expensive spray bottle packaging, keeping one for shop and one for kitchen.
After shooting, at the range, spray enough through the chamber and down the bore that it drips and runs out. Take care not to get ammonia based cleaners on the bluing or wood finish. It can damage them. Swab the bore clean and dry, and you are good till you can clean it normally when you are home. Some folks stop at the bore and the bolt face. You can also take it one step further and clean the disassembled bolt as well as the receiver.
Note: Cleaning with water based solvents leaves moisture behind. Sometimes it can be difficult to get it out of the tight spots and interior surfaces. This is why black powder shooters often use boiling water... it evaporates nicely on it's own. If are are particular, you can use hair dryer to warm the bolt and the receiver enough so it's warm to the touch. This helps it dry after cleaning with water. Maybe too much for some folks, but if it's needed, it's not too hard to do.
At home, remove the bolt from the rifle, disassemble and lay them out on an old clean towel. (Do not use your spouses good place mats or guests towels though I have "accidentally" cleaned something on that really ugly pink towel set someone that didn't know me very well gave me for Christmas).
Give the parts a nice even spray of the Windex, paying special attention to the bolt face.
Then wipe down with another clean rag (I like old shirts cut up), removing grime and excess cleaner .The rest of the bolt parts you would clean as you normally would after a day at the range, (You're soaking in it!) Now it's time to tackle the rest of your favorite bolt action.
Using a cleaning rod and cleaning jag, push the patch that's been lightly sprayed with the "Windex" through the barrel and remove at the muzzle end.
Now take one of your shorter cleaning rods that you'd use on a pistol with a cleaning patch loop attached to it. Place a patch in the loop, lightly spray it with the window cleaner and swab the inside of the bore and receiver. Take your long cleaning rod and jag and clean the rifle's barrel thoroughly as you normally would using your gun solvent. Then run a few dry patches throughout the rifles internal surfaces.
Take that short rod out with a fresh cleaning patch loop attached to it and soak with some gun cleaning solvent. Swab out the inside of the bore and receiver, then run some clean dry patches through the internal surfaces.
Finally, run an oil soaked patch over the internal surfaces (using some clean ones for excess), assemble the bolt back together and lightly coat with oil.
I think that's it, folks, now time for a clean up of my own.