My limited experience of 'old' rifles is that they shoot well and usually better than the operator. I think it is a perception that 'old' rifles didn't shoot well because that is what we expect of 'old' rifles. Due, I think, to indifferent ammunition, indifferent sights, poor care, indifferent shooting skills, poor memory, etc.

I have a Stevens 22/410 that will put just about any 22LR ammo in about 12mm at 25m, built in 1937. In spite of the poor sights. My BSA No 1 Mk III*, built about 1922 I think, did about 50mm at 100m with 30 year old military ball.