Re: Leupold or Night Force
You’re comparing scopes that have a doublet objective lens (Monarch and VX-3) with scopes that have a triplet objective lens (Nightforce). The triplet objective will have higher resolution, especially when the elevation and/or windage adjustment is set to a large value. About 20 moa from the mechanical zero is where resolution begins to degrade for a typical doublet objective. Loss of resolution is quite noticeable above 30 moa. The Nightforce has higher resolution at the mechanical zero and out to at about twice that adjustment value (greater than about 50 moa from mechanical zero). Do you know what the elevation and windage adjustments (from the mechanical or optical zero) are on your Monarch?
I’ve not been favorably impressed with Monarch resolution in side-by-side comparisons. I suspect that the Monarch erector tube optics are not quite up to par with, say a VX-3 or Zeiss Conquest. So you may see an improvement in the VX-3. Do not expect the VX-3 to hold up to a Nightforce, though, especially if the the VX-3 has a large elevation or windage adjustment.
There are so many other variables here, it’s impossible to predict how far you could see bullet holes with your new Leupold. Turbulence in the air is huge factor. Optical resolution at typical range conditions is usually limited by turbulence-induced image blur, not by magnification. The amount of image blur from turbulence depends on a lot of factors. Temperature, terrain, weather, time of day, height of the scope above the ground, size of the aperture are the major factors. 20X should be enough magnification to see all the details that can be seen through turbulent air (middle of a sunny day over flat terrain). On cool, cloudy days near sunrise or sunset, the turbulence could be so low that high magnification will allow you to see incredible details. Those are rare target shooting conditions, however. Are you comparing your scope with your friends’ Nightforce under the same conditions?
The theoretical limit of resolution at 400 yds is about 4 mm. That’s barely small enough to actually resolve a bullet hole under the best conditions. In this case, target contrast is also a big factor. If the target is black and the background behind the target is sunlit terrain, the hole will appear white on black and be visible at longer distances than for a lower contrast target (i.e, a buff target). This is the same reason we can “see” stars at night, although they are far too small for our eyes to actually resolve. Are you viewing the same target design as your friends, with the same background behind it?
The are personal factors that you should consider. Is your reticle focus (diopter) set properly? Is your scope focus set properly? Should you be wearing vision correction, for example for astigmatism, but are not?
For two scopes of the same objective size, properly focused to the target and your eye, set to the mechanical zero, at the same time of the same day, positioned next to each other, and looking at the same target, you will likely see very little difference between between them in terms of resolution if the turbulence is high. If you do the same side-by-side comparison when there is very little turbulence, I think the Nightforce will always win over the Monarch or VX-3. If you then set both scopes to 30 moa elevation, I also think the differences will be even more dramatic.
So,... if you want to always see the same details that your friends can see, I think you should cough up the extra dough for the Nightforce.