How do I use a bulk loading caulking gun?

There are two primary ways to load bulk caulk. One thing they all have in common is a properly maintained gun. The barrel should be clean and lubricated. The Pistons must be oiled and not excessively worn. The rod should move freely back and forth when the recoil is depressed.
1.) Direct from a pail: In addition to lubricating the inside of the barrel, spray a light lubricant such as WD-40, 3-in-1 or cooking spray on the exterior barrel cap threads. Remove the cap and nozzle assembly from the gun. Immerse the gun into the material to a depth of about 1". Move it about slightly to completely wet the barrel to ensure an air seal. Pull the piston rod back slowly, sucking the material up into the barrel. As the level of material in the pail decreases, sink the barrel deeper to avoid drawing air. When the barrel is full, remove it from the material. Clean the barrel first with a Spatula or Bucket Scraper, then wipe the threads clean with a rag. Invert the gun and tap the side to burp out any air pockets. Replace the cap and you're ready to go.
2.) With a Follower Plate: These handy accessories fit snugly inside 2-gallon or 5-gallon pails. There is a threaded ring in the center to accept a 2" diameter bulk guns such as the DL-45 or DL-59 series. It has has the added advantage of keeping air and other contaminants out of the caulking.

• To operate, place the Follow Plate directly into the caulking and press down firmly to remove air pockets.
• Remove the front cap from gun and advance the rod as far forward as it will go.
• Thread the gun into the Plate.
• While exerting pressure down onto the plate, and pressing on the recoil or thumb release, pull back on the rod to fill the gun.
• When full, unthread the gun from the plate and replace the cap and nozzle on the gun.
• Cover the opening on the follow plate with a piece of plastic to limit material contamination and curing between fills.