All it takes is an extra turn on the Lee FC die, or different primers, or hot weather, or different brass, etc. and you find yourself in the 50K psi range. What's funny is that you don't gain a thing by pushing the cartridge/rifle this way.
DLA-I e-mailed Lee Precision about there crimp die and pressure after hereing on the Marlin forum how a heavy crimp increases pressure.There reply was,there is only so much energy in a given load.Like the load in question(Marlin Talk)It was under published max in powder charge but velocity made it a max load.Velocity is the key to being safe and not being 50,000 CUP.Granted with H-4198, 2.5 grains of powder takes you from 39,400 CUP to 49,100 CUP and velocity goes from 2002 fps to 2108 fps.That is where the use of a Chronograph is a must to be safe.The Chrono is one of the most important tool's there is to keep your loads in the safe zone.
You don't gain a thing?Really.Here is a comparison of a .308 bullet in the .308-.06 and .300 Win Mag.Same bullet,different velocities.180 grain Nosler by federal
308 Win--2620 fps--2743 energy
30-06 Spr.--2700 fps--2913 energy
300 Win Mag--2960 fps--3502 energy.
Same .308 bullet at different velocities.Seems to me you gain alot especially for the longer shot's.
45-70 300 grain Nosler and Factory 300 Partition Gold from Larry Weishuhun and Rick Jaimeson both in Guide Gun,Rick's is in the .450 Marlin.
45-70 Factory 300 grain Partition Gold.
1826 fps--2223 energy
.450 Marlin Handload with 300 grain Nosler
2333 fps--3626 energy
1400 ft lbs of energy is alot to be gained,I think.
Just my opinion.Jayco.
