This is why "punching" the back of the hammer cut out is never successful and often leads to further wear and slackness very quickly .
Absolutely agree Gunman - this is why I call it a bodge method - it will tighten up the slop in the hammer but does not have the longevity of other methods. I used this method a few years ago on a pretty clapped out hammer gun I use pretty regularly. I used a large punch with a rounded face, with the hope that it would move more metal around, around the axle hole and it did a pretty good job I haven't shot the gun much recently but did use it eight days of the season last year.
Often on old guns the hammers have been levered or twisted off the axle by someone levering between the hammer and lock plate, and you can usually tell by any marks that might be on the back of the hammer or on the lock.
When removing the hammer its better to gently punch the axle/tumbler out from the hammer to prevent wearing the tapered join.
