HOW DO I BUY A GOCK 30 GEN 4 ONLINE FOR DUMMIES

My second G30SF also had precision challenges and also the WORST bring about pull of ANY Glock I've at any time owned, and I could NOT correct it applying this setup it doesn't matter what I did and nicely over one,000 rounds of trying to take care of it and “split in” the gun (which I haven't had to do with any Glock before both).Is one a litt