I’m not sure why a bolt-action anti-tank rifle only has 15 rounds of ammunition, while a semi-automatic one has 20. Not to mention, the Japanese were able to fire freely with their heavy, 50+ kg, seven-shot anti-tank rifle.
Yes(At least give it 20 rounds or some other buff.)
No(Fifteen rounds are already more than enough—I never even use them all.)
This is a weapon featured in the Battle of Moscow campaign. When compared to Germany’s anti-tank rifles, their magazine capacities are actually quite similar. I think this discrepancy stems from the lack of unified balancing between campaign-exclusive content and tech tree weapons.