Finally got a cheap SKS that I wanted to to experiment with. The price was right - $180 + $8 shipping, but the bore is a sewer. The rifle is very strong, but there are pits in the middle which are huge - more canyons than its. When the patch passes this area I feel tearing of the threads.

What should I do with the bore like that? Opinions and suggestions are welcome!

Shoot it?

Wow! Sounds like a serious gunsmith job...

Ever wanted to make an SKS pistol?

I recently resurrected a WW-II era barrel (mfr date 10-42) that had some rough spots like you describe. It took a while but I got it cleaned up and it shoots great.

Start by plugging the muzzle with a cork and securing the barrel so it's vertical. Fill the bore with a penetrating oil like KROIL or whatever you have in the garage for rusted hardware. Let it soak for a couple days.

Drain the penetrating oil and start with a brand new silicon bronze bore brush and brush until your arm is sore or the brush is worn to the point it just slides through the bore easily. You can also start with a (one caliber smaller) brush wrapped with fine steel wool. The point of this operation is to get all remaining rust and fouling out of the bore.

Now go find a good steel cleaning rod. GI cleaning rods are great for this next step. Also get a couple of extra patch loops that fit the rod. Plug the bore about 1-1/2" down from the muzzle with some moist paper towel. Make it a tight wad. Melt some bullet lead, place one of the patch loops in the bore, holding with a pair of pliers, and pour the lead into the space around the patch loop stopping before it fills the crown of the barrel (if any). Let cool.

Now secure the barrel in a vise using blocks of wood. I use a hole saw that makes a hole slightly smaller than the barrel and use it to drill between two pieces of hardwood with the pilot drill following the part line. Makes a great clamp and doesn't mark up the barrel.

Using a mallet, tap the end of the rod and work the lead plug loose in the bore. From this point on let's call it a "lap".

Working it out of the barrel, apply some valve grinding compound and work it through the bore. Make sure the rod can swivel so the lap follows the rifling. Work with the coarser lapping compound until the bore is smooth then change to the finest. You may have to make another "lap" or two. When finishing you could go all the way to jewelers rouge and have a nice shiny bore if you want to.

Chances are a heavily pitted bore will only become smooth if you do this with some pits remaining. Shooting will foul them first and subsequent rounds will pack the fouling in them. Patches will come out dirty but at least the rifle will be "shootable".

OR just buy a box of "Fire Lapping" bullets from Midway or Brownells. You'll need .311" bullets and I don't know if they're available. If not you'll have to settle for a "Hand Job"

deadshot2 . . . so at the end of that operation you have a bore that is shy, but still has "holes" in it where there was pitting and corrosion earlier, correct?

So is the bottom line that it is now shootable, and cleanable, but not necessarily accurate?

deadshot2, thank you - I will do as you say.

MadPick, I would guess that the reason the accuracy deteriorates with the bore corrosion is because uneven surface damages the bullet. So if the pits are filled with fouling (I was thinking about molly) and do not rip the surface, they should not destroy accuracy. Or am I missing something?

What type of SKS? Yugo? Romanian?...Most have a chrome bore, a few don't...

Yugo.

Here is a 99 cent solution. Get a can of Coke. Plug one end of the barrel. Pour the coke down the barrel. Let it fizz and do its thing. Let sit for 20-30 minutes. Drain barrel and brush with bronze brush. Put a few patches down...check barrel condition. Krioil and all that are nice, but coke will give a 100% clean of the bore. Yugos were not chromed...so the barrel may be screwed...I suggest a new barrel, if that is the case..

Yes, there will probably still be some pits where the corrosion was deep but less deep enough to compromise the barrel strength I would worry less about them than any asperities where there is metal or hard corrosion protruding into the bore. The "low spots" often pick up bits of metal from the bullet and it smooths them out somewhat until the next agressive cleaning.

As for the bore being slightly enlarged, bullets do funny things. They "obturate" or mushroom when they are hit by the pressure from burning powder.

I'd rather shoot a rifle with a few pits in the barrel than one that has corrosion enough to catch the patch and tear it.

As for accuracy? If I recall correctly this was an SKS the OP was talking about, right? Can you use "accuracy" and "SKS" in the same sentence?

Not like sks were meant as sniper rifles. They are lead sprayers. Would be cool to see if a pit or two really had much effect on accuracy. I got a couple we can use for comparo