We had feather picking problems from early on (we got our chicks mid May) and we tried many solutions. In the beginning, they were in the brooder too long while I built the coop and run. We noticed one of the gals was getting pecked badly and another one was getting it a little, too. So I built a bigger brooder and that stopped the picking. Then it started up again. We finished the coop and put them in, that helped for a spell. But they started in again and there was some nasty damage. We bought some Rooster Booster Pick-No-More lotion and it worked like a charm...for a while. We started noticing more of the girls getting pecked and realized that it wasn't just one culprit like we thought, but a couple of them. We painted (yes, with a 1" paint brush) the Pick-No-More on their butts and tails daily and that stemmed it but only for so long.
This was very frustrating, we were at our wits end. We seriously thought we would have to just kill them all before they killed each other. Then we found the Pinless Peepers. I was kind of freaked out about putting the regular peepers with a pin that goes straight through their nostrils, in fact I was kind of worried the pinless peepers would hurt them, too. The peepers were easy to use and they bugged the hens for a little bit, but they got over it pretty quickly.
My tips:
1) Have someone hold the bird while you put them in - holding their heads was not necessary for us.
2) Put the peepers in by bending them to flex the pins apart - the tip in this thread about hot water is great, we didn't need it though.
3) Angle one pin in first, then the other - chickens have soft tissue on their nostrils you should avoid pinching.
4) Put them on all of the chickens - we did anyway (6 hens...er...one turned out to be a roo) - when the first one got them in, the others started pecking at them.
5) Leave them in all the time - unless a problem arises from them - we didn't have any complications and we probably will take them out and clean them after a while.
We just took one of them to a farm as she turned out to be a he. I removed the peepers before sending him off to his new home. The peepers looked pretty clean, a smidge of dirt around the tight area by the nostrils, but clean on the pins. I assume they will be fine with them in for good.
I would recommend trying every solution possible before using the peepers, but if it's a matter of the birds killing one another, then these are definately the way to go. I read about the Pick-No-More lotions working for some and not for others, so I guess the same may be true for the peepers. I would love to hear if anyone else has had similar or contrary experiences as ours. Hope this helps someone...