With the A-TIPS 300 PRC outperforms 338LM.
Just like we saw up until few years ago the in 6.5mm standard sized cartridge space there is competition in the long action magnum cartridge space right now. 6.5 Creedmoor won that war which is excellent for those that shoot 6.5cm because there's more people using it which means more rifle's chambered in it more ammo for it and reloading components for it and all at lower prices due to economies of scale. Right now in the magnum cartridge space we're about where we were in 2015 in the 6.5mm cartridge space.
You have to look at your options today and to look to future at how things are going to play 5, 10, 20 years from now. IMO 300 PRC is going to win this fight it's going to be the prevalent long action cartridge in the future and anybody shooting 300NM or 338LM will be a rare oddity just like anyone shooting 260 Rem or 6.5x47 rather than 6.5cm is now.
I think the absolute K.O. blows on why 300 PRC will win out against 338lm, 300NM or other competitor are because;
#1. 300 PRC factory Hornady match ammo can be had for $1.62/round online compare that to $3.75/round online for 300NM or 338LM and it's no contest. You have to remember that most shooters don't reload so when they see the price of 300 PRC ammo being only 43% of it's competitors they're not going to look twice at the other calibers. 300 PRC is such a new caliber that most people don't know about yet but when the masses realize that they can get 338LM or 300NM performance at a very affordable price alot of people who have always wanted an ELR magnum but have been put off due the costs will jump into the water with 300 PRC.
Link; Hornady 225gr ELD 300PRC ammo for $1.62/round at Classic Firearms
# 2. The DOD has just officially adopted 300 PRC and ordered their ASR Barret MRAD's in 300 PRC. We all know we know what wide spread military adoption can do for a caliber and 300 PRC has just recieved it outperforming 300NM, and 338NM in the process. Just more nails in the coffin.
https://www.tactical-life.com/news/department-of-defense-hornady-300-prc/
#3. 300 PRC outperforms 338LM.
Here's ballistics for a 24" barrel 338LM with 300gr Berger VLD's using posted velocities from Nosler for 300gr bullets with 24" barrels at 2750 fps. If any 338LM guys are going to be upset by this comparison take note that I could have used Berger's posted load data but that's only 2700 FPS from a 26" so I'm using Nosler's.
The 300 PRC is also from a 24" barrel and velocities are Hornady's posted load data using 230gr A-TIP's at 2850 FPS. To keep things fair I'm using posted load data from major manufacturers on both not any individuals claimed numbers.
Both are ran at 5000 ft/alt
Note that 300NM is about 50-70 FPS faster than 300 PRC and that's something but it aint much in the grand scheme of things. Then you consider that 300NM is more expensive to load for and it doesn't have affordable bass cased ammo. I know 300NM guys are playing up the Lapua brass which 300 PRC doesn't have but you have to look to the future Lapua will get forced into 300 PRC just like they were forced into 6.5 Creedmoor. If you want to make money selling brass then you've got to sell brass in popular calibers and 300 PRC will soon be more popular than 300NM if it isn't already.
338LM top
300 PRC bottom.
The 300 PRC has less drop, less wind drift, slightly more supersonic range and 338LM's energy advantage at ELR ranges is not much the difference in spotting shot here is probably more or less a wash. Also this was using 230gr ATIPS rather than the 250gr ATIPS because Hornady's posted load data for the 250's tops out at 2700 FPS which seems strange to me that they 2850 FPS for the 230's but only 2700 FPS for the 250's. It's also good data point to note that the 230gr ATIPS $0.10/ea cheaper than the 300gr VLD's.
I remember a few years ago when 6.5x47 and 260 rem guys would tell you that 6.5cm sucked because at the time 6.5cm didn't have any Lapua brass and how'd that arguement play out long term? Of course 6.5cm dominated market share because it had affordable ammo when the others didn't and Lapua went into the 6.5cm market because they want to make money. Brass just isn't an arguement you can bank on long term.
Note post edited to include load data from manufacturers since it was suggested that I had "optimistically fudged the numbers in favor of my favorite" although no explanation of how was given.
Notice that Berger's load data for the 338LM gives a max velocity of 2700fps for the 300gr VLD but this is with a 26" barrel (Hornady's load data is for a 24" barrel) this could be because the 300gr VLD is longer than Nosler's 300gr bullets and thus leaves less room in the case for powder. I actually used Nosler's 2750 fps for 300gr pills in 3338LM on the charts in the comparisons above to give 338LM the best velocity possible based on actual manufacturerers load data for both cartridges and not considering any individuals claimed velocities. Thus note that with 338LM this comparison is made are using one manufacturer who makes a higher BC bullet and a different manufacture who posts the highest velocity but with a different bullet.
