I'm with Phil on this one. Enthusiasm is great, but it must be tempered with some control. Call me a wuss if you like, but I do most of my work with a 2.2lb hammer. If I REALLY need to break out the whup-ass I pick up my 3lb hammer. That's the biggest hand hammer in the shop. That said, some number of years of practice have given me a little bit of hammer control, and I can move more steel with that 2.2lb hammer than a lot of guys can swinging wildly with a 4lb hammer. If you really have to swing a 4lb hammer that hard on 1in stock, you probably either aren't heating your steel enough and making too much work for yourself (you're going to reset grain in the HT anyways, run it at almost welding heat), or you're trying to prove something. Either way if you work smarter, you'll save your body a lot of wear and tear over the years. Sure, it doesn't seem like it to you now, but it will matter a lot in your future.
You've got a small press right? Why not use it to break down stock?
-d