According to Ken Rahn's table summarizing the bullet fragment weights (at:
https://www.kenrahn.com/JFK/Scientific_topics/NAA/NAA_and_assassination_II/The_fragments.html ) which is reproduced
here:
there was 1.361 grams of copper jacket recovered from CE569 PLUS some undetermined amount of copper from CE567(which with the lead core weighed 2.89 g) PLUS a full intact bullet CE399, (which had a total weight of 10.277 grams including all the lead).
Two simple questions:
1. How much copper (by weight) does a Western Cartridge 6.5 mm bullet contain?
2. What was the weight of copper recovered from CE567?
If the answer to 1. is less than 1.361 g. + the answer to 2. then the fragments represent 2 distinct bullets.