/diy/ - Do It Yourself

>>2780104
I need to make a deep hole on a 4140 steel bar.
The bar is 20mm in diameter and the hole needs to be 12mm in diameter and 20cm in length.
It's sort of like making a gun barrel, but since that's not the intended use I won't need to worry about rifling and such so it should be a bit easier than that.

Now I realize this is a really deep hole and I will need specialized equipment. My question would be what is the cheapest piece of equipment I could buy to make this repeatedly, reliably and easily? It's not about the money, it's more of like I don't want to buy a lathe because it's sort of a shame to buy such an important tool if it's just going to do that one thing.

Wondering about the HP needed for such a task too

Generally speaking, if I wanted to make a precise and smooth hole in a piece of steel, the process to do that would be drilling it first, then boring, then reaming, right? But can I skip a step in the process if it's a small scale one off job? Like, just drill it and then ream it assuming I can get a bit and reamer in that size? If it isn't obvious I know nothing about this stuff so I'd be hiring a shop to do it.

>>2765084
Reaming tool.