Another way is to cut the curve out and weigh it. Bolck off the paper around the figure, weigh,cut, and weigh again. Simple, and accurate.
Good Luck!

You can view the data in a PT trace file and, if desired, import it into a spreadsheet where it is easy to tabulate.

You also would have to include the push the bullet continues to receive AFTER it exits the muzzle.

You would also have to know when the bullet exits the barrel. I have reason to believe the PT exit time is not reliable.

You also would have to account for friction and heat losses. I don't think they would be significant, but I could be wrong.

It's an interesting concept. Thanks for reminding me.