Mk II cleaning damage

[edwardware]

As Fogerty said, "It ain't me!"

My first sidearm, purchased used at Riley's in Hooksett, with my dad, at 21 years old, is a Ruger Mk II Gov't Target. I haven't shot it much since I became serious about shooting (15+ years) but pulled it out a few months ago as I'm thinking on teaching my daughters to shoot.

. . . and it's unbelievably inaccurate! A group at 4 yards (yes, 12 feet) is 2" across (bench/slow fire). I can tear off a single raggedy hole with any other pistol I own (including other Mk IIs) and none of the ammo I've tried makes any improvement.

Off to borescope. . . yikes:


It appears that a monkey with a chainsaw file dug out the leade almost a caliber deeper up the bore at 6o'clock. From the breech there's visible asymmetry to the chamber/leade step. I can't see a chamber reamer doing that, so I have to assume it's damage from a cleaning rod, but it must have taken thousands of strokes. The rest of the rifling looks good, and the muzzle is properly dressed.

- Am I correct in thinking I've found the problem?
- Would it be possible to bore and line it, and stop short of (or recreate) the weird feedramp?
- Does anyone (now that Clark gave up) make new screw-in barrels?
- Could I improve the situation by throating deeper so the leade was symmetric (but way too far forward?

ETA: I apologize, I presumed that a thorough de-leading and re-seasoning of the barrel was SOP for rimfire accuracy issues. That is the first thing I did; no change.

 

[Slamfire]

The barrel is toast. Clark is good, also see what Volquartsen offers. I have seen a number of Volquartsen match Rugers on the firing line. While it is at either, get them to do the trigger job!

 

[Steve762us]

I can't figure out those pics--any chance the barrel is leaded up? How'd it shoot when you put it up, 15 years ago?

 

[ColtPythonElite]

I am betting the barrel is full of lead

 

[Don_P]

I am betting the barrel is full of lead

Agree

 

[Blue68f100]

Time to get the copper ChoyBoy out and see if you can clean it up. Have to be careful with the ChoyBoy since a lot of it is copper plated steel, so take a magnet with you to confirm it's copper. I would first let it soak in Kroil for 24 hr before trying to clean it out. Then wrap 1 strand around a wire brush and pull it through. You will know real quick if it's lead. It will take some time to remove all of it. My guess is that someone was shooting Rem ammo through it. That ammo and foul a barrel quicker than anything. If you have access to one of the electrolysis cleaner it would be a good option too.

 

[EMC45]

Let it soak with KROIL for a few days and then hit it with a cleaning rod wrapped in 000 steel wool. I'm betting it will come sparkly clean. I also can't tell a lot by the picture.

With .22 the only issue with corrosion I've ever seen was with turn-of-the-century guns. Nothing that new.

 

[Howland937]

I just bought a TacSol Pac-Lite threaded upper for my MK3. It's got a great feel. Haven't shot it yet however. If yours is beyond repair, I got this one for like $250...maybe not as glamorous as Clarke or Volquartsen but quite a bit cheaper if it's something you don't shoot often.

 

[EMC45]

Let it soak with KROIL for a few days and then hit it with a cleaning rod wrapped in 000 steel wool. I'm betting it will come sparkly clean. I also can't tell a lot by the picture.

With .22 the only issue with corrosion I've ever seen was with turn-of-the-century guns. Nothing that new.

I meant a 22 bore brush wrapped in the 000 steel wool

 

[Blue68f100]

You don't want to use steel wool. It will damage the barrel. The reason I said Copper ChoyBoy .

 

[EMC45]

You don't want to use steel wool. It will damage the barrel. The reason I said Copper ChoyBoy .

000 is like cotton.... Some Chore Boy that is available is copper plated steel strands, so you have to be super careful. They cheaped out on it several years ago. A magnet will stick to some of the "copper" chore boy. That's why I recommend 000 or even 0000 steel wool (even finer). Brass wool is another available option.