The one case I'm aware of (thanks to that known gunwriter) was not a self defense case. In a nutshell, the wife was dead, the husband said she shot herself. The crime lab said she didn't, based on the amount of gunshot residue, she was shot from several feet away. That made it murder, and husband was so charged.
To further complicate the matter, the reloaded ammo used came out of a box that had (at least) two DIFFERENT loads in it. One light, one not.
The defense argument was that the prosecution was wrong, that she shot herself, the lab was wrong, the light load left less GSR and so APPEARED to be a regular load fired from further away.
There was apparently no way to determine what the round FIRED had been loaded with. As noted, your records are suspect, simply because you are the accused. As mentioned, there is no way to prove that the round(s) fired were the same as your records (if any) indicate.
Likewise there is possible doubt that even remaining unfired rounds in the gun are the same as the round(s) fired. Because you handloaded them.
Factory ammo is a "known standard" that the court accepts. Handloads are not, and cannot be.
