I decided to make a small guide for going to steel/iron dragons.
Their best drops are Draconic Visage, Dragon Plateskirt, and Dragon Platelegs.
They are located in Brimhaven dungeon (made from Zybez.com)
Heres a picture for you.
Recommended lvls: 60+ range/mage, 34 agility, 30+ Woodcutting, 43+ prayer
I take Diamond (e), Emerald (e), and normal Mithril bolts and look how i do.
Don't worry about Ranging and Maging them. They will not walk to you during combat.
NOTE: If i was in any real danger... i would not wear my Void.
As Evil Bob said, You may take range pots and a Beast of Burden (summoning monster that holds stuff) if you like.
Before entering the dungeon... take 875 gp... thats the entrace fee. You will also need an axe to cut through vines that block your path. Their are mainly 2 ways to get to the dragons (above).
Once you get there, take a does of Antifire potion right away. The combined effect of Anti fire shield and the potion will make their fire hit constand 0's. pay attention though... the potions affect will wear off. you will be warned before it wears off but its hard to see because you chat box will be flooded. just take a few food incase.
While in combat against these dragons, stand back. You can stand anywhere in here. If you are mage/ranging them they will not walk to you. Irons can be killed fairly fast... but steel dragons take a little longer. When you kill one they will drop their type of bar (steel dragons drop steel bars), Dragon bones, and a random item. Get what you want and get ready.
When you are ready just teleport out OR run out.... doesn't matter but be careful.
ENJOY!