A general mountaineering axe when held in your hand with your arms at your side should come close to touching the ground.
A technical ice tool/ski mountaineering axe is typically shorter, anywhere from 10-20 cm.
The length you opt to select will be based primarily on the use and your comfort on varying steep terrain. If you solely want it for steep couloirs I would roughly recommend something in the 55-60cm range (caveat, I don't know how tall you are or the length of your arms).
I have a BD Raven and have beaten the hell out of it for the past 4 years. Very durable, but coming at the expense of additional weight.
I like the shorty for riding because it isn't so cumbersome, but it's still (just) long enough to use while climbing steeps. Plus, with my CAMP USA aluminum crampons, the axe/crampon set up weighs in at about a pound!
For riding I would get a short axe (50-55) because it will be good for holding while descending and swinging around. A shorter axe will be less good for using a walking stick but you'll have poles anyway. I also like a light axe like the Grivel Air. I think that Raven is a heavier axe better for longer lengths and general mtneering. IMHO.
Edit to add: it will spend most of it's time on your pack so shorter + lighter = more better.
But in general, as stated by others, you want the shaft length to be long enough so that when you are holding the axe in a self arrest hold at you side, the spike should reach the bulging bone in your ankle. It used to be thought that it should reach the ground, but in reality, that's a little long (great for flat glacier walking, and I have a long one for just that) Plus, longer shaft = heavier axe.
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Joined: Fri Nov 12, 2004 1:43 pm Posts: 442 Location: Western Washington
I am currently using a Cassin Dragonfly (9 oz. and discontinued) 50cm as a self-arrest tool only. Straight shaft, all aluminum. Useful for soft to harder snow, nothing else. Also have a BD Black Prophet 50 cm, useful for those scary places I shouldn't be but end up in. Straight shaft also. Notice a trend? Good for plunging into the snow, boot-axe belays, impromptu anchor duty. What I need to do is get the Whippet thing going, makes a LOT more sense ascending in split mode, useable for self-arrest going down, just not as sturdy shaft-wise as a good axe. How you size your axe will depend on what you use it for, but I recomend short for self-arrest.
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