Hello. I attempted to use my hammer ramset tool to fasten a 2x4 to the concrete however using the ramset tool my nails stick out of the 2x4 about 1/4"- 1/2" and are not flush with the wood. Because of this I cannot place the sliding glass door into the frame because I did not account for the extra 1/2" that the nail would be sticking out from the wood. Any tips or advice on how I can make these ramset nails flush with the wood so that I can ensure my sliding glass door is sitting on a flat 2x4 surface before securing it?

EDIT: I want to add this important detail here. It is also worth mentioning that this 2x4 was not secured or screwed to the jack studs on the side of the frame. I had just put liquid nail on it when I attempted to nail it and what happened was that the nail actually only chipped the concrete. I've used this ramset nails and ramset tool on the other 2x4s in the same garage and had no problems but the 2x4s i nailed it into were secured on the sides to the rest of the frame. Sorry for being a noob but I'm trying to learn.

Why would I need to use a heavier load if this load worked perfectly fine in other areas in the same garage? Am I just in error and that problem was caused by the bottom plate 2x4 not properly being secured to the jack studs?