Some of you younger shooters may have never even heard of “corrosive ammo”. Ammo made before around mid-1950 used primers with mercuric salts in the priming compound in the primers. Upon firing this ammo, these corrosive salts were deposited all inside the barrel of the weapon.
If these salts were not removed, they would attract moisture and corrode (rust) the inside of the barrel. Swabbing the barrel with oil would not stop this process. They would rust under the oil.
The only solution is to remove the salts. This is easily done by using a water-based solvent, or just water. The barrel must then be dried and then oiled to prevent rust.
Some may ask, “Then why would you want to shoot that nasty stuff?” The answer is that it is now very cheap ammo and, other than the corrosive problem, the ammo shoots just fine.
For example, nowadays, you can purchase 8mm Mauser ammo very cheaply.
I bought some for less than 9 cents per round.
It is Yugo surplus, 196 grain Ball, corrosive.
This ammo shoots great, fires 100% of the time, and is accurate.
But, it is not ammo for the “lazy” shooter.
You must be willing to immediately clean your weapon after firing the corrosive ammo.
Here I am shooting it in my Yugo 8 mm Mauser, which was made in 1948.
The rifle was manufactured, coated in Cosmoline, and put in storage.
I bought mine a few years ago, cleaned it up, and had a brand new, 50 year old rifle.
It was near to my heart because we were both born in 1948.
The bore is perfect and the rifle is very accurate.
Here I am working the bolt while the rifle is still on my shoulder, the way you are supposed to do it.
When you are finished for the day, remove the bolt and spray Windex down the barrel.
I use Windex with ammonia, but many feel that this is not necessary, as it is the water that really does the trick.
I agree, but feel that the Windex does no harm and might help wash out any fouling.
Spray it down the barrel until it comes out the muzzle.
Then push a patch through the barrel.
Spray some more down the barrel and run some more patches through the barrel.
In this picture, you can see the water running out of the muzzle as the patch is pushed through.
Also spray the bolt with the water solution and dry it.
Repeat this several times, until the patches are clean, then run a few dry patches to dry the barrel.
I then spray WD-40 through the barrel.
I then patch it dry and spray WD-40 once again for the ride home.
Once home, I used my regular cleaning method to clean the barrel.
I like a half and half mixture of Kroil and Shooter’s Choice.
I scrub the bore with a bore brush and patch it until clean.
Then I lightly oil the barrel for storage in the safe.
Sounds like a lot of trouble?
Well, you get a brand new barrel only once. If you let it rust, there is no way to restore it to “perfect”.
A little trouble and you will always have a “like new” firearm.
It’s worth the trouble!