Aluminum would be softer and easier to work. Heck, even lighter to carry, too. What can I say? I'm a fan of the steel. I have gotten pretty good at the "keep your fingers anywhere but where the hammering is going on" part. The key is to let the vise do all the holding. I could hammer on it all day and it wouldn't complain a bit. As far as the hot metal shavings go, just use gloves and an appropriate face shield. The danger is all relative to your experience working with these tools and the safety precautions you take.
The hammer is used to
form the butt-stock only, as I can't bend steel that thick with my bare hands and lack more sophisticated tools to do it. It just bolts in place on the blaster, no "persuasion" needed. Everything just slips into place with a flick of the wrist.
Here are the pics of a vintage Star Wars stormtrooper blaster, circa 1978-ish. I can certainly say they don't make 'em like they used to.
Note the tabs under the barrel and the corresponding slot on the stock.
Here you can see the knobs that lock the stock in the open position. The plastic is flexible enough to take the stretch required by the arms.
The rear endcap comes off with a slight pull, allowing the battery hatch to open. This was later moved to the handle when they changed to an "AA" battery configuration.
The new ones don't feature the yellow and black "barber-pole" which spins inside the barrel with a really loud, parent-annoying, "Look-at-me-I'm-shooting-bad-guys" noise also made by bits inside the barrel. The new ones also lack the 3-position stock although you can see where it used to attach to the gun in the later versions. :cry Law now requires the blaze-orange endcaps on the guns in the US as well, same story as the Han blaster (made sure I got one of those, too). The vintage blaster rifle shows up on Ebay from time to time, and it's a fun piece to own. Not cheap, but some of the older stuff just can't be beat...
Once again, big thanks to WackyChimp for the hosting.