How does the TKb-022PM function / operate with the magazine so far rearward in the stock?
That’s a good question the TKB-022PM is on of Korobov’s designs which placed the magazine to the very rear of the weapon. Most bullpup designs today like the LA85, Tavor, FAMAS and the Steyr AUG place the magazine with the rifle’s bolt and chamber - normally about 3/4 along the rifle’s full length.
The TKB-022PM instead uses as vertical bolt, unlike the AK and AR the gas system surrounds the around the barrel in a sort of loop this moves the bolt backwards once fired, ejects the round, moves the bolt (literally) up and down and a u-shaped ‘rammer’ brings the next round forward from the magazine. This unusual configuration allows the rifle to minimize its length and have the magazine positioned all the way to the rear.
I hope that explains it, I’ve never had the chance to look inside one so I’ve only been able to explain it as clearly as I can from what I’ve read. Thanks for the question!
You can find the original post about Korobov’s bullpup designs here.