KJV Onlyist Error: The Septuagint

KJV Onlyists believe that the KJV translators solely used the Masoretic Hebrew text. However, it is very clear that their translation was frequently augmented by the 2,000 year old Greek Septuagint. While there are many passages that can be used to show this, I will use Psalm 22:17, verse 16 in the King James Bible, as a demonstration. The Masoretic Hebrew text for this passage reads; For dogs have surrounded me, the assembly of the wicked have encircled me, like a lion at my hands and my feet. Now lets take a look at the LXX, which reads; For many dogs have compassed me, the assembly of the wicked doers has beset me round, they pierced my hand and my feet. Now let's compare these with the KJV; For dogs have compassed me: the assembly of the wicked have inclosed me: they pierced my hands and my feet. It is pretty obvious that the KJV translators were using the Septuagint in this verse as the Masoretic Hebrew texts reads 'like a lion,' while the Septuagint has 'they pierced.'