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Hi i had a 305 that was rebuilt in 2012 and to this day it only has 6000-7000 miles on it... long story short i was at the our local car show this weekend and we getting ready to go on the dam cruise to show all the cars off to all the campers... well halfway through it my timing chain snapped and i sm clueless on what could have caused it to break any ideas???

What kind of timing chain was it? Was it a cheap $30 one?

May have just been a chain failure, I have a double roller chain in mine, been in there since 1984.......Did the chain actually break or was it a sprocket failure? I have heard of some problem with lower quality sprockets.

I have also had a Crank Keyway snap on a car that I bought that the previous owner had changed the cam and chain, he installed a 4 degree advanced crank keyway and it snapped. If it was an OEM replacement "silent" chain, they can stretch and snap. But sometimes things just break.

If a timing chain breaks after only 6000 or 7000 miles, there's really only two possibilities-
1- It was a defective(and most likely cheap) chain.
2- It was installed improperly.

I once had a chain fail in a race engine; a double roller, I had visually checked it when I bought the engine used; everything was tight and appeared to be fine. But 30 or 40 passes later, the chain in a dozen pieces along with a pile of shrapnel had liberated itself out of the hole it tore in the front cover. A spectacular failure at 6000+RPM that also bent 11 valves and 5 pushrods.
Post mortem revealed the most probable cause- a 3-keyway aftermarket bottom gear, mated to an OEM chain and top gear. Obviously not compatible in some way(pitch, or possibly roller size) the chain had sheared ALL THE TEETH from the top gear before it failed. Somebody cheaped out, or possibly just didn't know any better and put some mis-matched parts together, with disastrous consequences.

Im thinking a tooth snapped off the gear and got caught in the chain which snapped it and sheared all the teeth off the crank gear... it was only a single roller chain...