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Hi All
I was just reading a post on a different forum where someone was complaining that, on a particular rifle, the scope wasn't mounted to the barrel, so was less accurate. I've also read that the distance from the barrel also makes a difference to accuracy and ability to hold a zero.
Does this really make that much of a difference on a .22? What about something bigger, .308/7.62?
What about receiver mounted optics?

What do you guys think, any practical experiences?

Cheers
Dean

If a rifle has a wobbly barrel it orobably should not be shot. I can remember some break barrel air rifles with barrels that wobble or fud not return to the same position. So in that case, using sights on the barrel makes sense. The same could be argued for semi auto shotguns.

The hight a scope is above a barrel will not affect accuracy but it will equate to requiring more adjustment as the distances change.

DM

The key thing to remember with accuracy, is repeatability/consistency.

If a scope is mounted somewhere, providing it is in the same place relative to the line of the barrel every shot then it should be accurate.

The barrel would be the ideal place, IF, mounting a scope on the barrel did not effect the consistency of the shooting. A lot of people will argue about the harmonics of the barrel and suchlike, however it would be consistent.

Provided the receiver of the rifle in question was solid and always lined back up perfectly with the line of the barrel from when it was Zeroed it should make no difference where the scope would be mounted, this is why rifles like AR-15's although folding the entire upper system folds with it so the scope sticks relative to the barrel and does not adjust the zero. Rifles where this does not happen, or where scopes are mounted on the stocks of free-floating barrels would be therefore less accurate when any movement of the barrel/action occurs.

It would make a difference on any rifle of any calibre, but with bigger calibres you are likely to shoot longer distances, so the inaccuracy would be more apparent.

I'm sure someone will be along shortly and put this in easier to understand language, but that's my understanding on it.

TL:DR - If the relationship of the scope is directly proportional to the barrel, where it is mounted should not come into question, if the surface the scope is mounted on can have a variance that is not directly related to the barrel, accuracy will be diminished.

Most Russian military optics mount on the left side of the receiver with an almost universal rail and sit offset to the left of the bore, usually so the iron sights can still be used with the optic mounted.The scope on my SVDS sits way to the left of the bore and due to the way it mounts it holds its zero regardless of how many times its removed and refitted, its the same with Aks etc.

The height of the scope above the bore may not affect benchrest accuracy, but , unless you can guarrantee that you will never shoot with the rifle tilted, it certainly affects practical accuracy.
Fred

Good point Fred, something I forgot.

Again though, it comes down to consistency.... if you consistently shoot tilted you can zero to your tilt... but any variance will effect accuracy, more so the further from the barrel.