Last spring the local range had a company come in to demo their gun care products. As part of the demo, they were offering a free cleaning to anyone interested. The idiot, yes idiot, used a stainless brush on a steel rod to scrub my 22/45 bore from the muzzle end. I noticed no degradation of accuracy after his hack job.
He was:
Stupid.
Uninformed.
Lucky.
I was:
Stupid. (To let him do it)
Lucky.
Not overly concerned, because I wanted to see what kind of abuse the 22/45 would stand up to.
On the Ruger, clean from the breech, buy one of the little trigger assy guards and you won't have to take it off the frame as often. Be careful and avoid using brushes, most of the time you don't need them, a wet patch works just fine. Wipe the rod clean so it doesn't collect dirt, the dirt will do more damage than a soft metal rod. I like brass rods because they are soft yet strong, and look better than aluminum. Plastic or nylon rods bend, metal doesn't, so an oops is less likely, other than that, Dr. Rob is 100% on IMO. Most Rugers (22's) are overcleaned and killed with kindness.
In answer to your question, I doubt if you damaged it. This time anyhow. You can use a pair of reading glasses or a magnifying glass to check the bore around the chamber area in the Mark II after a wet patch or two. If there is any lead or crud, you may need a brush to work it out. I use a spent .22 Stinger case to scrape the sides of the chamber clean instead of a brush, followed by a patch of #9. That gets that ring of crud a whole lot faster and easier than anything I've found.
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