So, in previous threads it became clear that regardless of whether you like the PatMarlins gas check maker or the other guy, they are both capable of making good gas checks. I went with PatMarlins for a 30 caliber maker and am happy with it. I was looking for accurate, repeatable results, not necessarily speed and that's exactly what I got. I like the two step process and am happy with my purchase. I am using .015 copper for the Lee 312-155-2R bullet.