Here is what to check when your rifle’s accuracy suddenly goes astray.
1) Check the scope rings and base screws. Always start with the obvious.
2) Check the scope’s click adjustments. How? Simple. Just attach a collimator (preferable a magnetic one, like from leupold), then check to see if the crosshairs move exactly one inch both horizontally or vertically using the right number of clicks (eg, if your scope has 1/4 minute clicks, then 4 clicks up at 100 yards moves the point of impact one inch high).
3) Check that your barrel is free floating. If you gun has a wooden stock, its especially prone to warpage. Check to see if you can slide a sheet of paper all the way down the barrel channel without any contact. Use a fine grit sandpaper to fix this. Don’t sand away too much, just enough to relieve contact.
4) Check the bore and give it a good clean to remove all copper fouling. Use GunSlick brushless bore cleaner to remove ALL traces and layers of copper fouling with ease.
5) Check the crown for nicks or uneven wear. This ruins accuracy. Get your gunsmith to recrown.
6) Older handloads may need to be reseated to break the bond between bullet and case. This slight bonding raises pressure, which can throw that fine tuned load off, thus accuracy can suffer.
7) Check the throat, just forward of where the lands begin. Hot loads tend to erode throats faster. You could reseat the bullet out a little further to fix this, or have a gunsmith turn the barrel in a turn or two, then rechamber. The worn section is now gone. This is cheaper than rebarrelling.
