Put the summary of the bug you're having here

What I expected to happen was...:
When a block is mined, the entity drops near where it was mined from.

What actually happened was...:
At random, the entity of the block that is mined shoots several blocks away sometimes into solid walls causing it to despawn

Steps to Reproduce:
1. grab any tool,
2. cut down trees, mine in tunnels (multilevel tunnels show it best, mine on lower level and watch as some of the blocks go through 2 solid blocks to the upper level.) etc.
3. look around areas that were mined for entities that went flying.