Well, ....... not to, '
rock the boat' but your friend told you wrong. In order for your handloads to, 'count against you' the prosecution would have to be able to demonstrate that: (1) Your reloads grossly exceeded the specifications for typical law enforcement ammunition (A reality that is very difficult for any reloader to achieve without risking damage to both himself and his pistol); and (2) by loading your handloads in this manner, you had a deliberate and malicious intention to do harm.
Does that sound like you? If so you may be at fault. However if there is, (1) no demonstrable malicious intent, (2) no provable desire to cause excessive damage; and (3) your handloaded ammunition is charged with no more than published, '
top of the chart' powder charges (along with conventional design bullets) then I very much doubt that any court would find you to be legally culpable.
PS: Yes, I've read the popular, '
horse hooey arguments' that reference differences in velocity, and target distance as adversely affecting the outcome of somebody's case; but, last time I looked, there was very little case law to establish any such documented supposition. (You've got to keep things in the, 'real world'; and, of course, as they apply to YOUR particular situation.)
I got married in 1973, and began reloading shortly thereafter. Neither do I have any idea how many 1,000's of times I've carried my own handloads for self-defense. Until, '
what's his name' started writing about it, the use of handloads for self-defense was honestly, truly, never an issue. Frankly I'd rather find something else about guns - something that's much more likely to go wrong - to worry about.