Don't rely on your local sporting goods store for reloading advice.
Don't necessarily believe your chronograph if it's an inexpensive one and you're shooting in changing light conditions.
Stay within the maximum loads given by the bullet manufacturer. All bullets of the same weight are not equal when it comes to generating pressure.
When you say "I was loading to 100% of the fill ratio and higher," if by "fill ratio" you mean maximum charge listed in your reloading manual, stay at or below that. Until you have more experience under your belt.
Smokepole gave you some sage advice right there. You would do well to heed it.
GB
