Absolutely correct, and the reason is all cast bullets come out of the mold lopsided/non-concentric. Now it's time for those to chime in and say, "not my bullets they are perfectly round" but before you post, roll your perfectly round cast bullet on a concentricity gauge and post the video.
Non-concentric has nothing to do with the alloy, a quality mold or experience of the caster. It has everything to do with the physics of the cooling process; a poor quality mold could make it worse.
For full power accuracy at long range a bullet must be concentric, otherwise it will start to wobble and when it does the wobble only gets worse.
To help offset the issue, rifle bullets with maximum barrel contact and minimal nose typically work the best. A perfectly installed gas check can provide a flat perpendicular base and powder coating a jacket.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |