There are many examples in the English language where two different words can have the same meaning, or refer to the same object. When it comes to the material that you hold onto a handgun, grips and stocks mean the same thing.
Some people just can't get over the way they understand the meaning and make a big deal out of it. This person used this term, this other person called it that, this book said that, this other person said that, this company called it this thing, this other company called it that; blech!!
Most of us understand what is meant when either word is used, and just continue on with our happy lives... Use whatever word makes you happy, I've got your back, got you covered, got your six, etc...
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