As other have said above; shot placement and velocity is important. The mono need speed to be effective as they don't have a soft core like lead core bullets. The weight of the bullet is not important, it is how fast it is traveling on impact. I work on 2100 - 2200fps as a minimum velocity, then you can work out the maximum terminal ballistic range - providing you hit bone!
The results when working within the above parameters can be impressive! Especially on big body animals.
I have also seen some not so flash results when the projectile has not meet enough resistance on impact.
I tend to use these kind of loads as a spook and shoot type scenario. For instance I have a 6.5 prc shooting the 120ttsx at 3320fps, with my rifle zeroed at 300 yards(3 inches high at 100) I know I can point and shoot out to 400. Anything beyond 400 I tend to dial up with a softer fragmenting projectile, in my case the 147 eldm.
Hope this helps
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