2 year old crate-motor
350 Chevy
86 Blazer
6,000mi on it

At the end of a 200mi drive the engine started to miss.
Quite badly. Limp home 15 more miles.

Next day do a cold compression test.
All cylinders look reasonable with the exception of one that reads zero.

Easy to check for broken spring. Pull off the rocker cover and the valve springs look okay.

Could be a hole in the piston?
Could be broken rod?
Could be a failed rod cap?
Could be a burnt valve?

What else can it be?
What is your guess?
Why would a valve burn or a piston hole after 6,000miles,
during an otherwise, run-of-the-mill trip?