Fill water caner over 1/2 full of water and bring to a simmer. Wash jars and screw bands in hot soapy water, rinse with warm. I place my jars into the caner with the basket raised upside down to sterilize while preparing jelly.
Place peppers into a 6-8 qt saucepan. Add vinegar. Stir in pectin. Add butter to reduce foaming. Bring mixture to a full rolling boil (A boil that will not stop bubbling when you are stirring) on high heat. Stirring constantly, stir in the sugar. Return to a full rolling boil and boil exactly 1 minute while stirring constantly. Remove from heat. Skim off any foam with a metal spoon.
Ladle immediately into prepared jars, filling to within 1/8 inch of tops. Wipe jar rims and threads. Cover with 2 piece lids. Screw bands tightly. Place jars on elevated rack in caner. Lower rack into caner. (water must cover jars by 1-2 inches). Add boiling water if needed. Cover, bring water to a gentle boil. Process 10 minutes. Remove jars and place upright on a towel to cool completely. After jars cool, check seals by pressing centers of lids with finger. If lids spring back, lid is not sealed and those must be refrigerated and eaten within 3 months. Sealed jars should keep in a cool dark place for a year.
Be sure to wear gloves when working up the hot peppers.