How to model a perforated cone in solidworks
Pretty easy to make almost perfect!
Removal of material from a sketch on the face and then a second removal of material with circles arranged in staggered rows of the first, but on a plane shifted by 12 degrees (axis of the cone) for a repetition of 15 times the two removals. Make sure both sketches are centered on the vertical through the origin
To get your basic shape, I'd make 3 work planes the needed distances apart for the 50, 25, and 60 mm diameters. Then draw a circle on each workplane of those diameters all centered. Then use the loft command and select all 3 circles to make that general shape. For the holes, it could get a little more complicated. What is the exact pattern of the holes you are making?