How to get started in Gunsmithing...
First learn "How to File"...from that, all other trade abilities will follow.
The Community trade courses to familiarize yourself with the use of a lathe, Mill, Drills, etc at the very basic level, including Thread cutting, dividing, drilling and tapping, and the Maths behind all these things.
All the "Gun Familiarity" in the world is of no use if you can't make a repair piece properly, or tap a hole in hard metal.
AS an example, a friend of mine ( our friendship started over a Hand-built Hotchkiss MG) started his working life with a traditional Fitter and Turner/Tool and Die maker apprenticeship...in the days when one spent a couple of years learning how to do things with a file ( and very little else).
Just before he turned 60 ( yes, 60) he decided he liked the look of the M1909 Hotchkiss Portative, as used by his great-Uncle in the Great War (Palestine, 1917)...He got a 1/4 scale drawing ( used by Army Armourers to ID parts) some photographs of an example in the Infantry Musem, and a few measurements with a set of calipers on said original. Some 350 hours later for the Cavalry Model, and about 250 for the Tank model, he now has TWO, Replica ( non firing) Hotchkiss Mark I guns, which one can't tell from the originals, unless you try to pull the cocking handle---it is solid.
And we developed the stamping dies to make the 30 round strip for the guns as well...and they work in real Hotchkiss-type guns (Japanese Nambu....).
The clincher is that he built these two guns with a File/s, a small bench top drill press ( your $99 special), and a borrowed Lathe for the round barrel fins etc.
Shows that learning to "File" well can get you anywhere. ( look at the Gunsmiths of the Khyber Pass-Northwest Frontier of Pakistan....
SO, get those basics under your belt, then Read-Read-Read....and practice on scrap steel, brass, aluminium, etc, and on "Old Guns" ( those ruined Bubbas which have no collectibilty left because they have been butchered by idiots who wanted to "Improve" a Military rifle.
Patience and a steady hand and eye will get you a long way.
From a self-taught "Gun Wrangler" of the Movies...I still get my friend to do the complicated bits...( Like new trigger-guards for MG08/15).
Regards,
Doc AV
AV Ballistics Film Ordnance Services
Brisbane Australia.