Originally Posted by venomballistics

Going by the account in post 1, I'm thinking that you got crossed up just prior to committing to the run load.
If you worked up to it properly, there would be no surprises like this.
Could be that you read 15 on the scale in development, but thought 16.
Could also be a failure to zero the scale.

Guess that means you have a few bench gremlins to hunt down.