Canadian Bushman
Well-Known Member
I know BT bullets are accurate as well but the inherent accuracy of flat based bullets seems amazing to me. Why is this?
Cleaner release, and inherently more stable(and not just due to length).
In addition to the other comments, flat based bullets normally have more bearing surface and tend to seal faster when fired.
Some boat tailed bullets have a very short bearing surface and some barrels/twist don't like them.
J E CUSTOM
Does the larger bearing surface contribute to accuracy in other ways beside aiding the flat base to seal to the bore?
I'm referring to muzzle blast across the back of the bullet. A flat base presents smaller area than boat tail area, and it's perpendicular to centerline(rather than more parallel).
Flat base bullets generate considerably more base drag, which pulls back center of pressure to shorten the Cg to Cp moment arm.
The fb bullet designs are also usually more tolerant to slightly out of spec barrel diameters, which is why I suspect some of my factory bbl.'s only tolerate them and not any bt's.
Again, this is because of FB bullets large bearing surface and its flat bases ability to easily obturate to the rifles uneven bore?
Do bullet manufacturers purposely use a concave base instead of a truly flat base to enhance this property?