Recent bottling problems

[drycreek]

I bottle my homebrew, which has worked fine until the last 2-3 batches, which I've felt were undercarbonated. There are a couple potential causes:

1) I normally get prepackaged priming sugar (4.5 oz) from my HBS to go with each batch. For whatever reason, I didn't order that for the last couple batches, and ended up measuring out 4.5 oz of corn sugar per 5-gal batch. It's possible I made a measurement error. My scale sucks, so maybe I'm just measuring out too little.

2) There could be something wrong with my bottle caps. I typically throw a bunch of them in sanitizer solution prior to bottling, use as many as I need, then dry the others off and return them to the main bag of bottle caps. It occurred to me that the process of getting wet and drying back off without actually being used on a bottle could have a negative effect on the seal. In other words, I should only put caps in the sanitizer if I actually intend to use them right then.

I have a batch (5-gal saizon) I plan to bottle in about a week. I ordered the prepackaged priming sugar this time, as well as new bottle caps. Is there anything else I'm overlooking here? Is one of these factors more likely than the other?

 

[basilchef]

one poss explanation could be an under mixing of your priming solution. The new caps and sugar should fix your problem though. also i would recommend using a priming calculator online to get exact measurements for your carb levels based on what type of beer you are making. too much and you have bottle bombs, too little and... well you know what happens. cheers.