The .224 Cal and FMJ bullet's are very remarkable. I have experimented for years with them in the .223 and the 22-250. Both are fully capable of killing deer effeicently. Now, for the use of FMJ bullets. If you have ever tried them, you will find that they do not react the same way consistantly. Meaning that sometimes in a given situation, they will leave a tremendous wound channel and exit wound , other times they just punch a small hole with minimal damage. However, if the bullet strikes in the vital area of the body the animal will die shortly. There is asignificant difference in the kinetic energy transfer between the .224 cal and larger calibers. Ultimately, it is the hunters choice to pick the weapon and caliber he/she feels appropiate to ethically harvest an animal. So, with all that said go enjoy the hunt.