How weapons would be in 21st century If all guns were muzzleloaders?

( I decided to move this thread from History reaching to sometig more logical )
Sory for the poor cualaty guys, Im not English or American, I hope that I'm not poting this website I also have notion that I'm hilly probably righting an mess.

Yes, I'm talking about an pure fantasy alternate history like scenario wen primers never were invented, because somehow chemicals are less technologically advance, but teres still exist electricity, the same kenoladge abut almost everything...

How weapons would be in 21st century If all guns were muzzleloaders?