Breaking in boots

I'm having a tough time breaking in my new SCARPA SL M3 boots. So far i've walked about 30km in them. My last walk was 15km on the weekend. The boots are a relatively good fit but I'm having trouble with blisters on the heels. One boot is worse than the other. The problem is generally friction when I am walking up hill. I wear two pairs of socks currently - a woolen Injinji toe sock and a traditional hiking sock. I'm switching to coolmax injinjis with a hiking sock outer since I hope that they will be less abrasive. I'm still waiting for the coolmax socks to be delivered.
The boots themselves are actually 4 years old since I was told that they are a superseded model. Maybe a long shelf life has allowed the leather to get a bit too tough?
A colleague at work suggested wetting them and then going for a short walk in them. I'm not sure if this is a good thing to do.
Any suggestions?
The boots themselves are actually 4 years old since I was told that they are a superseded model. Maybe a long shelf life has allowed the leather to get a bit too tough?
A colleague at work suggested wetting them and then going for a short walk in them. I'm not sure if this is a good thing to do.
Any suggestions?