37mm fin stabilized chalk round with screw on top for commercial aluminum hulls

37mm fin stabilized chalk round with screw on top for commercial aluminum hulls, sold by a set of 10. Color random. The screw on chalk cup holds the chalk powder more securely and the assembling is easier than the slide in type. Use “20OFF” for a 20% discount if you buy more than 5 sets. Download link here if you want to print it yourself.

This projectile is compatible with 3″, 3.5″(w/ powder bushing), and 4.5″ aluminum hulls. Please check your hulls against my pictures to make sure you are ordering the correct size.

Included items: base plate, fin, chalk cup ×10 each. Not included: primer, hull, black powder, chalk. They are only in the pictures to show you the loading process.

Loading Guide (video):

1. Prime the hull.

2. Pour 60 grains of black powder inside the hull.

3-4. Put a base plate into the hull and ram it down with a 1″ wooden dowel. (thinner steel punch works, too)

5. Push the fin down the hull.

6. Load the chalk powder into the chalk cup.

7. Screw the fin onto the chalk cup in the same direction shown in the picture.