BP research with 1000 fragments, not 100% success

I have just lost 1000 BP fragments trying to search the assalut rifle BP. “Original” assault rifle was just repaired, 100% good. Boosted with the maximum amount of BP fragments: 1000. I got only 94% chances of success. Why not 100% ?? Moreover, thanks to fate, 94% was not enough, so i lost the good rifle and the 1000 Bp. Please explain what went wrong, thanks.

There is nothing wrong here as the gun had either already been used or was found with damage to it so the % chance is always lower and doing a repair will not make it 30% again and its been like this since i can remember.

If that Weapon already got repaired once you cant get the weapon back on 100%