I love old axes and hammers. I've got half dozen axes or so and at last count around 30 hammers.
That looks like a tough using tool and a handy thing to carry in a truck.
I'm a big fan of wooden handles. While I was in school I worked for a summer framing houses. One day of swinging an Estwing framing hammer and my elbow felt like it was about to explode from the vibrations transmitted thru the metal handle. And just try choking up on a metal handle. The next day I had a Vaughn framing hammer with good old hickory--problem solved. I do like my little Estwing trim hammer with the leather handle. I kept the Estwing framer for rough work.
A properly hung ax or hammer will not fly off the handle. It's not that hard to do. Anybody who wants to learn how let me know and I'll send a link to a Forest Service publication and video with a great tutorial. Up until nearly the mid 20th century much of the continent was cleared by men with wooden handled axes.
Some time back I sharpened my grandfather's old ax, stamped "R. King", a Collins stamp used between 1830 and 1925. I don't think it had ever really been sharpened and was very thick behind the edge, like a lot of American axes were when new. Prob used as a splitter on the farm because it sure weren't no chopper. So I used the Forest Service gauge to set the edge geometry and filed it back and used a round stone to hone it. You can see the fan shaped area I filed. When I got done I went out and felled limbed and bucked up (mostly) a seven inch oak. When I got done I gave the ax half a dozen swipes on each side with the stone to touch it up and decided to check the edge. It did this to a piece of paper:
That was after cutting the tree and a very light touch up. I'd say the steel in this old tool is pretty good. You do want to exercise some care with an ax that sharp--it's a four pounder and if you bump into it it sure don't give--it just cuts the snot out of you.
In my truck I carry an old Craftsman boy's ax I gave the same treatment to. It's come in handy a couple of times on FS roads while I've been hunting.