The best I did with my Longbranch was 3 shots/100M/1 1/4" with basic iron peep sights, using Greek HXP ammo.
(I doubt I could do it now though, my eyes a re a bit older now!)
I think most fellas don't understand how to shoot with irons properly on a target, or tend to use a bull that is too small for their sights,that is why they can get better results with a scope."...What kind of grouping..." Depends on the rifle, the ammo and the mount used. A scope won't make a rifle that doesn't shoot well with iron sights more accurate.
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"...What kind of grouping..." Depends on the rifle, the ammo and the mount used. A scope won't make a rifle that doesn't shoot well with iron sights more accurate.
The diameter of the barrel has a lot to do with accuracy too. Lee-Enfield barrels can measure from .311" to .315" and still be considered ok. Over .315", the barrel is shot out. Using a .312" bullet, the most common commercial hunting bullet diameter, in a .314" barrel will give mediocre to poor accuracy.