This is my second home brew. I just did my boil and my OG reading was 1.055. The recommended OG was 1.061-1.065. Not only did my OG not reach the recommended value, my final volume of wort into my primary was only ~4 gallons ( from a 5 gallon kit). I believe my loss of wort was from the boil and the straining while transferring into the primary. My question and concern is about the OG and the final volume. Will the loss of the one gallon just cause me to come out with less beer in the end? Will it cause a change in flavor? Change in alcohol Level? Is it a problem that the 5 gallon recipe turned out only 4? I would appreciate help with this so next time I can make a proper brew! Thanks!
The way it sounds you brewed up a kit which recommends a partial boil. I do these also. The kits are designed to meet the recipe OG if you have the correct volume of wort in the fermentor. Your kit recipe has a range for OG, but the range will not affect ABV by much.
It isn't necessary to take a kit OG because the OG will be in the range specified by the recipe if your volumes are correct. Use the recipe OG for your notes.
Volume in your fermentor is the larger problem. Are you using a carboy or bucket to ferment in? Did you add a measured 5 gallons of water to your fermentor and mark this level before your first fill with wort? Without having the 5 gallon level measured and marked you really don't know how much wort you have. This may affect FG, but will affect calculations like ABV greatly.
Buckets with gallon/liter markings are notorious for being incorrectly marked.
As an example this is what I do with an extract kit. Partial mash is slightly different.
I start with a measured 2.5 gallons of water in a 5.5 gallon kettle. I do my boil and chill the wort in the sink with ice and water. The wort gets chilled to about 68°. I don't measure the temp. The lid just feels barely warm.
Second step is to add 2.5 gallons of chilled water to the carboy fermentor. The wort is then added to the fermentor. I pour through a bag to take out most of the hop material.
I then add water to bring it up to the 5 gallon mark which accounts for the boil off and the half cup liquid left in the bag strainer. I don't try to calculate boil off and add that volume ahead of time. I usually add just under a half gallon to top off to the five gallon mark. Full volume of wort in the fermentor is typically 58° to 60°.
Shake and swirl until aerated froth is evident all the way to the bottom of the carboy. Pitch yeast.