Cheddite 20ga 2.75" 16mm Primed Paper Hull (100/bag)

Technical Guidelines for Loading Paper Tube Hulls:

Paper hulls possess unique material properties that require specific mechanical handling compared to modern plastic cases. Adhering to the following guidelines will ensure optimal performance, prevent structural failures, and extend the life of your hulls.

1. Environmental Conditioning & Moisture Control

Paper and cardboard are highly hygroscopic and react significantly to ambient humidity. If a paper tube becomes too dry, it becomes brittle and prone to splitting.

· Avoid Dry Conditions: Never load paper cases in extremely dry environments. (For example, here in Minnesota our winter weather creates very dry conditions. Our local ammo company event stores their paper hulls in a large humidor. This is what is necessary to properly store and load paper hulls.)

· Pre-Load Conditioning: We strongly recommend conditioning your hulls in an environment with a minimum of 60% relative humidity prior to loading.

· The 48-Hour Rule: Open the product boxes 48 hours before loading to allow the hulls to naturally absorb ambient moisture and reach ideal elasticity. (A home humidor or even a poor-man’s humidor made out of Tupperware and a moistened paper towel or sponge is all that is needed. Check YouTube on instructions for making your own home humidor.)

2. Crimping & Closures

· Preferred Closure: A roll crimp paired with an over-shot closure disc is highly recommended over a fold crimp for maximum hull longevity.

· Fold Crimping (6-Star): If you choose to use a 6-star fold crimp, utilize a specialized crimping starter with radiused (softer) edges to avoid scoring or splitting the paper. MEC offers a MEC 12ga Smooth-Cone Spindex Head for Paper Hulls (#1308462S).

· Pressure Management: Excessive pressure or overly sharp crimp starters will pre-cut the paper, leading to mouth cracks upon firing.

3. Hull Mouth Prepping

· Mouth Opener Adjustment: Exercise caution when adjusting the depth of the mouth opener/re-primer tool prior to wad insertion.

· Avoid Over-Flaring: Setting the tool too deeply creates structural stress and invisible micro-fractures at the mouth, which inevitably develop into longitudinal splits during firing.

4. Component Sizing & Wadding

Because paper tubes are slightly thicker than plastic tubes, the internal diameter of a paper hull is generally tighter than that of a standard plastic hull. Components that must be forced into the case will compromise its structural integrity.

· Wad Dimensions: Over-powder cards and fiber wads with a relatively large diameter will overstress the tube and cause cracking. For example, for a 12-gauge paper hull, wads greater than 18.75mm (.738") in diameter can cause cracking. for a 16-gauge paper hull, wads greater than 17.03mm (.670") in diameter can cause cracking.

· Wad Selection: It is strongly recommended to use lubricated/waxed fiber wads. When using plastic wads, Mica Wad Slick is preferred.

· Insertion Force: Any component (gas seals, plastic obturators, card discs, or fiber wads) that requires excessive force to seat can create immediate or latent structural failure.

Note on Firearms: Shotgun chambers can and do vary by manufacturer and the age of a shotgun. Please be aware that shooting paper hulls in firearms with oversized or out-of-specification chambers ("wide chambers") significantly increases the risk of hull walls splitting or rupturing upon expansion.