Originally Posted by Fiftydriver
...Again, in this class of chamberings, you will see 15 to 18 fps per inch of barrel length for velocity increase.
Exactly, Longtimelongranger told me that year ago when I bought my lapua. I load my Lapua to get about 2700 and I have a 28" barrel.
The problem with the improved is that the hassle of fireforming the cases is not worth the added velocity gain. The Lapua is a very accurate cartridge but it not a super fast one. Velocity only gets you so far. If you want more then go with one the 338 edge. it is a 300 RUM necked up to 338. (FYI: the 338 RUM uses a smaller case that is why the egde uses the 300 RUM case which has more capacity) I believe he is getting a good 2900 from a smk. I can't recall exactly. The only thing required is a set of dies from redding. It pretty easy to neck up 300 to 338. And, you don't have to fireform. The only downside is that you don't get to use lapua brass but I believe Nosler Custom Brass makes 300 rum brass.
If you really want Hard hitting AND high velocity go with one of Kirby's Allen Magnums.