I can only speak from experience using Nightforce and March in F-class at 600 and 1000 yards. I don't know of anyone using a Sightron in F-class, though I'm sure there must be a few. The main ones are March, NF, Kahles, and I see some Vortices (Vortexes?) from time to time.
I shoot my March-X 10-60X56 HM at 50X all the time, year round in South Texas. Before that riflescope I shot a Nightforce NXS 12-42X56 at 40X most times, or dialed down to 30X when the mirage was bad. The NF doesn't hold a candle (in the wind?) to the March-X 10-60X56 HM when the mirage shows up. I will only refer to the March-X now, because that's all I've been using since 2012, and only the HM since 2019. My vision has changed since I used the Nightforce NXS.
The exit pupil at 50X is 1.12mm in diameter. That is not an issue for me when I'm in prone position behind my F-TR rifle. I would think it would be an issue in most other setups. But for F-Class that is perfect. I can actually see the writing on the NRA LR-1FC target at 1000 yards. I can't read it. I also see the ring numbers, but cannot read them. I do sometimes use them to hold on target; very useful when you need to hold a couple lines to the side. The picture of the target is clear and sharp, and when the mirage roams, you can actually detect the river it makes in the scope but the target is still sharp.
This past weekend, I shot a 1000 yard match in atrocious wet, damp, sticky, hot, muggy conditions (90f+, 130%+ humidity). It was one of my better outings in a while and I shot 196-10X in the first match. I had two pairs of 9s because I was not paying attention closely enough to the conditions. However for that 20 shot string, I had 10 of them in the X-ring, which is 0.5MOA in diameter. At one point, I had 5 Xs in a row, preceded by a 10 and followed by a 10 as the last shot of the string. My hold on that final 7-shot string was the ring number between the 9 and the 8 ring, that was with the additional windage dialed in the scope. With my March HM scope, I could place the center dot of the MTR-5 right on the ring number because I could see it.
This is where quality glass makes a difference. Yes, the exit pupil is small, but in my March HM, it's superb IQ and very usable.
Does that make me a magnification whore? You betcha, but I have the scope that provides excellent quality magnified IQ. And I have set it up on my rifle with a 30MOA cant; I want to use as close to the middle of the optical path as possible for 1000 yards.
(Before you ask, my next two strings were not as good, but out of 60 shots for record for the day, I coaxed 23 of them into the half-MOA X-ring. That's 46% of my shots inside of 0.5 MOA at 1000 yards with a .308. At the same time, the F-open winner had 54% Xs. I think he has a 7mm of some kind.)
. March has had a 5-40x56 for years, biggest deficit was lack of good tree reticle, but that has changed with the PDKi reticle in the Gen II. This Sightron should do well as they’ve always tended to punch above their class optics wise.
