In reply to andrewmcleod:
> Search for 'Myth 3'.
There is more to placing pegs than the sound they make for sure - although they sound they make does help to indicate how good the placement is - other factors such as how much force you need to hammer it home, how you placed it initially, the type of rock etc.
Like placing wires - you don't just tug em to check if they are OK - you check the soundness of the rock, assess the wire placement for being mechanically strong e..g how the nut fits the crack etc.
So placing pegs. Generally the best placement is a horizontal crack, which takes the whole peg up to the eye and is angled down into the rock. The peg would be mechanically secure and could then be hammered home.
In real life it’s a case of finding a suitable crack (which will tend to be vertical) and selecting a peg that best fits it. The peg is then placed by hand: half to ¾ of its length. It is then driven home by well aimed hammer blows to the head of the peg. I must admit I've found listening for the sweet music of a rising, ringing tone indicating a good peg. If the tone changes it may mean the peg has bottomed, or the placement has failed e.g. the rock has fractured. I'll stand by this as a/ I've placed more than a few pegs in my time - in winter b/ I've abseiled off them c/ I've fallen on two different occasions onto pegs I've placed - they held both times.