Anyone notice a change in accuracy while shooting with a sling attached to the barrel? Seems to me it should upset barrel harmonics. Haven't experimented yet myself, just a thought, my mind wanders

Nearly all my vintage German rifles have the front sling stud on the barrel and they shoot just fine. My two Mannlicher/Schoenauer's have the front sling stirrup that attaches with a screw through a lug on the barrel and through the forearm. The 1903 did require the wood be relieved around the sling stirrup lug but after that it shoots basically one hole at 50 yards and hovers around 2 inches at 100 yards with open sights.

I agree that it should change the barrel harmonics if added later but if the load is developed with it in place I haven't seen that it matters. If a fella is shooting long range competition I can easily see it not being desirable but that's a completely different kind of rifle.

I've got 4 pre 64 M70 custom rifles with a barrel band, no accuracy issues at all.

When I shoot my .416 (Mod 70) with a tight sling, it most definitely changes the point of impact - always lower, so much so I don't shoot like that in the field.

That has never worked for me, A tight shooting sling and a barrel band swivel seldom works, except on the internet at times..Ive tried it lots of times, gun always shoots low, the tighter the sling the lower it shoots..The barrel band was never intended to be used as a shooting sling, only as a carrying sling is pretty common knowledge...Might work with a bull barrel, don't know.