they did make one, it was called the gewehr 43. it was designed to be a multi task rifle, so they all had rails to accommodate sniper scopes but also had open sights so that they could issue it to general infantry.
the M1, even though it was technically the MBR of the US armed forces was still very limited in numbers by the US entry in 1941. the US had the thompson and the M1 but germany had the MP40 and sturmgewehr, a full fledged assault rifle, it wasn't until the war started going badly and germany started capturing russian SVT40s that they realized that a semi auto general issue weapon was necessary. by the time the G43 hit the scene germany was just not able to crank them out fast enough and compounding the problem, most soldiers(especially the snipers) preferred the mauser's accuracy, and simpler design.
ignore my complete lack of capitalization. I still have no problem correcting your grammar.
I never said half the crap people said I did-Albert Einstein
You can't believe everything you read on the internet-Benjamin Franklin
Bean counters told me I couldn't fire a man for being in a wheelchair, did it anyway. Ramps are expensive.-Cave Johnson.