I've got a 4" blued 586 that used to be a great shooter. I've put alot of 38spl through it so it had a ring built up in the cylinders. I used a bronze bore brush and powder solvent to break up the rings.
First time to the range its like the damn sights are loose. Shots are all over the paper, even from a rest. I didn't think cleaning the carbon out would do this. Anyone have a guess as to what the hell happened? The cylinder does have some front/rear play, but not alot. It isn't "spitting" lead.
Should I go through the hassle to send it to S&W? This used to be my favorite wheelgun....

ETA: I've only put FMJ Winny white box and .357 FMJ Fiocchi through it. Leading can't be the issue but I'll clean the snot out of it anyway. Thanks for all the replies.

I would send it to SW, couldn't hurt.
I'm pretty sure they all have a lifetime warranty.

sounds strange. clean the barrel, change the load, and check for anything lose all shit I'm sure you all ready did. what ammo are you using?

My first guess is a combo of lead and jacket material gunking up the barrel. Start with the dry bronze brush (use a new one, you likely beat the snot out of yours cleaning the cylinder) and go after the lead.I say to start dry as any solvent or oil will just lube the lead up and make it harder to scrape the lead out. Another great trick is to wrap a brush with copper pot scrubber piecies (chore boy brand from the supermarket or look alike stuff) if you use the pot scrubber it will mash the heck out of the brush so go with a beat one if you have it.After you have got the lead out switch to a good copper solvent such as BUTCHES BORE SCRUB or SWEETS to take care of the copper jacket fouling. Regular cleaning stuff such as HOPPES #9 works ok for day to day powder fouling but doesn't do much for lead or jacket buildup. Generally lead needs to be manually scraped out and copper needs strong chemical help to disolve.
After I get a bore very clean I tend to stick with either lead or copper bullets (one or the other depending on what type of shooting I want to do with that gun).Useing only one type of bullet seems to make it much easier to clean.A clean bore won't lead up much and if it starts a couple of minutes with the bore brush and its clean. After getting a slight haze of copper in a bore lead bullets seem to smear and totally muck up the bore and cleaning takes 40 minutes and a lot of work.
In my exprience a revolver has to be a total mess as far as cylinder gap and/or timeing before accuracy really goes in the dummper but a mucked up bore will cause all kinds of grif with certain loads.