Musketman and others,
I have shot a few artifacts through my repro. 1842 smoothie. I am lucky to live in the middle of the second most active Civil War location, southwest Tennessee. I could not resist firing a few drop quality.69 three ringers. I dug them from the Confederate retreat to Corinth , Miss from Shiloh. A waste of a artifact, sure, but it was my call. Now I can say I have fired a real .69 press lead bullet.
However, I would not fire the .69 Gardner you have pictured. I can dig the common .69 three ringer, cone base at a 100:1 ratio, to the steel cupped pressed .69 Gardner. those rounds fetch $65-$90 each, depending on condition. That bullet was made for smoothbores and rifle barrels. In theory the steel cup that held the paper and powder forced a mushrooming effectwhen fired. The same theory behind the box wood plug base .69 Mississippi rifle round. That bullet looks like a huge two ring Enfield round and will fetch $100 and up for excellent examples.
The Holy Grail of .69 cal bullets are called Missouri Hogs, a .72 cal single ring, deep based cone style bullet. Again looks like a huge single ring Enfield bullet.
The only thing that I will lay my traditional smokepole for, is to pick up the metal detector and find the real stuff.
Smokeblower