Originally Posted by royinidaho
now that I have the 375 I'm done looking. Kind of a peaceful feeling.
I can still feel and hear the 350's impact after shot from your AM this summer in Townsend.
Several friends are aware I have a 338AM that’s been in the works for the past two years. It’s an interesting discussion when they ask how much more range this will increase my hunting probabilities. When I reply in all practicality based off my most likely hunting conditions about 200 yards more over my 338LM, they kind of look at me funny. Cheytac parent case, 140+ gr powder, only 200 yards more than the 338LM what the heck!
Using the 338LM, 338AX. 338AM and 375AM as comparison. Assume all are capable of equals, that is same precision potential of .5 MOA or better, same muzzle variation of 15 fps or there about, and shoot equally under the same environmental conditions.
Using an air density equivalent of 3000ft DA and the following on a ballistics engine:
338LM, Berger 300 OTM, 2800 fps- red line
338AX, Berger 300 OTM, 3000 fps-orange line
338AM, Berger 300 OTM, 3400 fps-yellow line
375AM, SMK 350, 3300 fps-green line
Exploring energy, all are capable of producing 1500 ft/lbs at 1300 yards or beyond. Totally capable harvest energies for elk at these ranges.
Therefore, considering everything equal and sufficient energy, wind uncertainty is what limits maximum effective range. In most of my hunting conditions its not uncommon to be shooting around a 1.5MPH full value equivalent crosswind uncertainty. Assuming correct application for an accurate firing solution, I will apply an error equivalent to 7” of drift for wind uncertainty for an elk sized target. Just for wind alone, this leaves 7” left and 7” right or 14” potential variation just for wind uncertainty. Now you have to consider your precision potential combined with wind uncertainty but for this another topic.
Looking at the 1.5MPH crosswind chart and 7” of wind drift, MY comfortable maximum effective range for each cartridge:
338LM, 1000 yards
338AX, 1100 yards
338AM, 1200 yards
375AM, 1150 yards
So for my comfort levels, and most likely hunting conditions encountered, the 338AM only adds 200 yards to my maximum effective ranges compared to the 338LM and only 100 yards over the 338AX.
With a 2MPH uncertainty and using the same criteria:
338LM, 900 yards
338AX, 950 yards
338AM, 1050 yards
375AM, 1000 yards
With a 1MPH uncertainty and using the same criteria:
338LM, 1200 yards
338AX, 1275 yards
338AM, 1425 yards
375AM, 1350 yards
So where does one start to consider the advantages of the 338AM outweighing the advantages of a 338AX? I can see definite advantages when conditions are very predictable, but how often does this happen with my hunting conditions, not very. Therefore in my opinion will a 338AX with a lighter platform, better mobility, easier brass accessibility, better overall range capability such as short to long range hunting shots, and overall longevity to barrel life as compared to the 338AM accomplish 90% of my hunting shots. Yep. The 338AM will only extend my ranges by a few hundred yards in all practicality and many more under ideal conditions. Additionally the 338AM will shoot rocks a looooooong way out there, something my 338LM is not capable of.
There are advantages and disadvantages with every choice. We just need to be aware of them and ensure they fit what we intend to use them for. Bigger and “badder” not appropriately employed has little advantage if any at all over more reasonable, lighter, usable and efficient applied appropriately.