If conditions are right (light is good, no wind, etc) and I can see the target, less than one MOA five shot groups are a regular occurrence at 200 yards. This is with a 45 cal GM LRH (1-30 twist) barrel in a TC Renegade stock with an RE Davis trigger, Lee Shavers inserts in a Lyman front sight and a Lyman 57 rear sight. Bullet is just over 400 grains, paperpatched with 100% cotton 9# onion skin and sized for easy loading (little more than weight of my range rod), pushed with 80 grains of 3F Swiss, with an 1/8” thick by .50” diameter hard dry felt wad over the powder. At the range I use a damp/dry patch to swab between shots, but can easily load more than a half a dozen rounds without difficulty with no swabbing. The MOA accuracy holds out to 300 yards, but find that the Lyman 57 is starting to get a bit ‘wobbly’ when jacked up for the longer distances and if I were to get serious about long range shooting, would definitely invest in a better purpose built sight and possibly a faster twist barrel. I have been told that the 1-30 twist is marginal for the 400+ grain bullets, but as a hunting gun out to 150 yards or so max, the setup works for what I want.
What kind of rifle are you using?
What rifle are you using? What sights are you using? Are you shooting prone with sling or from a bench and rested (or other)? Have you tried 10 shot groups?
Try it with a 577 Enfield!
From the description of your rifle, I doubt that a new rifle would reduce group size. More practice with emphasis on load development would shrink groups, but not by much.
