I'm new to this forum, but not to guns. I have a rather perplexing question as to why certain manufacturers rifles seem to underperform and others over perform from factory specs. I have been hunting and quite successfully I might add, for the past 50 years. Recently I jumped on the bandwagon and went with a new lightweight rifle in a new razoo chambering. BTW, I began reloading more than 40 years ago, and rarely every shoot factory loads, unless economics dictates the cheapest way to shoot and acquire brass for a new project. Well this new rifle/chambering was going to save this old body about 2 pounds on those long hunts while still offering comparible performance to my elk rifle. I took extra care breaking in this new rifle, working up loads, and making sure I was happy with it before I hunted with it. Just to be upfront, I worked up loads without a chronograph. I thought I had a pretty good load going with the gun and went on an antelope hunt. Needless to say I was less than impressed with the performance. But I attributed it to bad karma. I then went on an elk hunt and was rewarded with similar results. The problem was I was putting bullets where they belonged, and animals were not going down as expected. This scenario repeated the next year, and I was thinking the bullets were the problem, I went to the manufacturer and got their take on the situation and they recommended a different bullet. In the meantime, I am super impressed with new rifle accuracy and convince several friends to invest in similar outfits. On, his brother owns a gun shop and has the same caliber but different make gun, as well as a chronograph. What he found out, our guns were consistently 3-400 fps slower than his rifle with his handloads. Just to take handloading out of the equation, I have purchased 3 boxes of different factory loads and chronod them to find out the velocity difference is consistent across the board. Now to recap, my new brand gun, plus two others all shoot 3-400 fps slower than the friends rifle and antoher make in the same caliber. We have all gone to the range on the same day and shot on the same ammo through 2 different chromos with similar results. Why?