What happened?

[Mooseheadpiper]

Hi Folks,
I've been shooting for almost two years now and have been working pretty hard lately on my accuracy. I usually expect to see a grouping of about 2" on a good day and maybe 3" at worst. Yesterday things fell apart. My shots were all over the place. And here are a couple of strange things. My technique felt right. I can usually tell if a shot is going to be a little off, but this time when I'd shift my focus from the front sight to the target I couldn't believe what I was seeing. The other strange thing is that this was with my Smith and Wesson 686 which is what I shoot the most. When I switched to another gun, my accuracy was right back to normal.
I'm planning to enter my first ever competition in a few days and my confidence is rattled. Any ideas what could have gone wrong?
Thanks in advance for your advice.

[Chuck Haggard]

What kind of ammo? Is it lead bullets? Could you have gotten things leaded up badly?

[HCM]

Did you check the sights to see if anything has come loose ?

[Mooseheadpiper]

Thanks for the ideas Chuck and HCM. I did check the rear sight and it seems solid and looks to be right where I set it. I've only been using American Eagle 130gr FMJ or the equivalent Federal white box I buy at the range. I'm pretty good about cleaning, but this time I went home and did a REALLY thorough cleaning thinking that something was messed up. I won't know if that helped until I go back to the range, and that might not be until I'm actually competing. Before I cleaned it I took a look inside the barrel with a flashlight, but being a newbie at this I don't really know what I'm looking for. Thanks again for the suggestions. Keep 'em coming please.

[Chuck Haggard]

If you only shoot jacketed ammo then you don't have leading. If the gun has been solid until now I would suspect it's the ammo.
Have you had accuracy issues with this same ammo before?
Is this new ammo that you just bought?
Have you tried different ammo to confirm the issue is with the gun?

[1slow]

Try different ammo.
Try same ammo in another known good pistol.
Have another known good shooter shoot the pistol.
Check the pistol mechanically: sights intact and tight, is the cylinder indexing correctly chambers aligning with barrel.
Just trying to reduce the variables and see what is out of whack.

[Al T.]

Betcha it's the ammo. I had two cases of Federal Champion that loved to sling bullets across the landscape.

[JeffJ]

I haven't shot factory ammo in a long time, but I've heard some pretty disturbing stuff about QC lately. Seriously, if they're going to hog all the powder they could at least make sure they rounds work well.

[Mooseheadpiper]

I've been using American Eagle ammo for quite a while now without any trouble, but I did just buy 20 boxes online from Alamo Ammo. I'm not sure but it's possible what I was shooting when I had trouble was the first box from them. I assume they're reputable enough that I got what I thought I was getting, right? Or maybe I just got a really bad box? Anyway, I'm going to try hard to get back to the range before my competition and try out different ammo, maybe shoot from a bench rest, have someone else shoot the gun, try the ammo in a different revolver etc. to see if I can isolate something. Thanks to all of you for these suggestions.

[ACP230]

Match jitters?

I was vibrating like a tuning fork waiting to go on the line at my first bowling pin shoot.