A common .44 bullet, the hornady XTP 300 grain hollow point has two crimp grooves. The listed hodgdon max load is 19 grains of h110/w-296. With the bullet seated at the upper groove I can still hear the rattle of powder in the case, no compression, although it is cose to seating atop the powder. This load is listed around 38500 CUP. Now, seating the bullet on the lower crimp effectively legnthens the case. Does this really allow you to throw an extra couple of grains in and not blow pressures of the chart? How do you work these up, by reading primers? I assume many of you have worked up loads for Marshall's dual crimp bullets.