oh my mistake. serebii doesn't have it listed as a egg move. who knew psypokes would be a step ahead o.o
i suppose it's because shelgon must be part of the breeding, rather the whole chain.
here's a suggestion for a moveset then:
Salamence @ Salac Berry
Jolly Nature
252 ATK/252 SPEED/4 HP
-Dragon Claw
-Fire Fang/Brick Break
-Substitute
-Belly Drum
same as Charizard. switch it into skarmory or something who will clearly switch out, set a sub, then belly drum, and Salac Berry will activate.
dragon claw has STAB and with fire fang, it covers everything except Heatran. Dragon Claw + Brick Break will cover everything as well, but the downside is that Brick Break might not OHKO skarmory.
the biggest problem with this moveset is ice shard and extremespeed. people who are not prepared will lose, but there are those who will foresee it and you will be doomed.
a better belly drum moveset i suggest is the following:
Salamence @ Yache Berry
Jolly Nature
252 SPD/64 ATK/192 HP
-Dragon Claw
-Fire Fang
-Brick Break/Roost
-Belly Dram
yache berry reduces ice damage. you basically use belly drum in against something like a skarmory or something else that knows it is screwed against any Salamence. this salamence will at least OHKO 2 pokes in a battle.
be sure, however, that you use it for the late battle. a lot of people prefer to pack ice attacks just for dragons, so make sure that it makes its appearance after certain sweepers are out of the way.