My dim recollection (obviously wrong) was that while the steel was in a semi molten state, it was squeezed through a mandrell (imagine tooth paste squeezed from the tube)into a ingot form, from there it was hammered into forged ingots later to be machined into anything from rifle barrels to an artillery barrel or whatever.. Sorry, I should have made myself clear.. I wasn't refering to hammer forged barrels as we know them today..

Thanks Jeff and Curl..

That stupid little question was nagging at me..