Does your SP101 have "rings" inside the barrel?

D

DirtyHarold

New member
If you own an SP101, with the cylinder open and unloaded shine a light at the firing pin (to illuminate the inside of the barrel) and look down the barrel from the muzzle end and see if you can see any faint looking ring shaped impressions in your barrel.

I'm not talking like scratches, just faint almost scuff like ring shapes on mostly the lands but also partially the grooves.

I just notices this in my SP the other day. Dont really notice anything in the GP100. Just wondering if any other SP's have the same thing.

I would post pics but cant get a good in focus one. theyre all totally worthless.
 
Most likely they are chatter / tool marks. How does it shoot? Does it seem to be accumulating lead or copper? If it shoots well and does not foul, then I would not worry about it. If it fouls easily and shoots poorly then I would call Ruger and get them to fix it.
 
I remembered this old thread and I was able to get a picture of what I’m talking about

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Sent from my iPhone using Tapatalk
 
What you are seeing there is typical of the way barrel grooves used to be cut.

Fist, a hole is drilled the length of the barrel. Often this hole is the final diameter of the lands, but a second slightly larger hole may be bored to straighten everything out. At any rate, this hole will often have circular tooling marks on it left behind by the drill. The tooling marks may or may not stand out, depending on how fine a cut was taken.

Then with button rifling, or other forms of rifling a tool was dragged through the barrel to cut the grooves deeper than the 'bore' diameter. This tool was dragged through the barrel lengthwise, so it often left lengthwise tooling marks in the grooves, while the circular tooling marks from the original hole remained on the lands.

That is what the photo you have posted looks like to me. You can see the lengthwise tooling marks at the bottom of the grooves, and some slight remaining circular tool marks on top of the lands.

One way of forming rifling that is becoming more common today is hammer forging. In this case, a mandrel with the reverse 'image' of the rifling is placed in a slightly oversized hole in the bore. The barrel is then hammered, reducing the outside diameter, which squeezes the inside diameter around the mandrel, impressing the rifling into the barrel. The mandrel then has to be pulled or pushed out of the completed barrel. I suspect slight lengthwise drag marks would be seen on all the interior surfaces with this type of rifling, caused when the mandrel was withdrawn from the completed barrel.
 
What about the cyclinder?

Thread revival:
Tough to eject using higher powered loads (still under max but I'm backing off from that) .. probably will solve the problem.
Hone it out?
Leave it be?
 

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chucky222 said:
Thread revival:
Tough to eject using higher powered loads (still under max but I'm backing off from that) .. probably will solve the problem.
Hone it out?
Leave it be?
Click to expand...
That is the result of using worn tooling. If they stick you can try lightly honing them but anything more aggressive will enlarge the chambers.

Jim
 
All of my Rugers have rings, as you describe them, in their bbl's. Driftwood's explanation is 100% accurate. And I'll add that I've never had an inaccurate Ruger revolver with one exception (a .45 Colt New Vaquero with undersize cylinder throats).

My experience with them goes back to the mid-60's and covers .22's, .32's, 357's, .41's, .44's, and the aforementioned .45 Colt. All had the boring rings left by the initial machining operation, and all shot very well indeed.

Too, if you're into lead alloy bullets, none of my Rugers except the .45 Colt until I had the throats opened up, would lead the bbl. with properly fitted bullets...ie. sized to fit the cylinder throats. YMMv but I'd say you're GTG with your 101. Rod
 
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