4? ball shell clearance in mortar

[TheSandmanIsMe]

I?ve always us paper ball shells in the past. They are 3-3/4? when assembled, and strips of paper are glued on in layers to make the O.D. Of the shell fit snug into the 4? I.D. Of the mortar tube. I?m trying the plastic shells this time. They are also 3-3/4? O.D.. I can?t find any info about wrapping layers of paper to build up and fit snug in the tube. Is paper layering the process for plastic shells?

[PyroJoeNEPA]

Most people just use a strip of fiberglass reinforced tape around the equator [after gluing the halves together]. Basically, that is all that is needed. The point of using the plastic hemi's is to save time not having to paste the shell and also to ensure the halves are "true" and not warped. Some people put a layer or two of tape over the plastic if they feel they need a harder break--[depends on what is in the shell]----.

[TheSandmanIsMe]

Thank you Joe, I will go with that.