My first two PCPs (Prod and Avenger) both have their scopes in medium height rings for a distance from the bore center to the scope center of about 1.5 inches. The P35 I got last Thursday is a bullpup with a center cocking lever that moves a rod above the bore of the gun. So the picatinny rail is really high and I needed high rings to get my face up enough to see through the scope. So the center line to center line is about 2.67 inches. Over an inch higher. I've been shooting groups to determine what projectile this gun likes (FTT pellets and Slug HPs seem to be the best) and also started playing around with chairgun to see what kind of range the different projectiles would give me. The velocities vary quite a bit with the 34 grain Slug HPs only going about 650 fps and the FTTs (20 grain) going about 850. I sight in to keep the mid distance rise to about 1/4 inch - so I can ignore it for plinking and hunting. With this criteria and the average velocity I got with each projectile, I get a sight in distance of 32-33 yards for both weight of JSBs and the Slug HP. The FTT may be able to be sighted in at 39 yards, however, due to it's much higher velocity in this gun. But just for fun, I changed the height of the scope to 1.5 inches. That dropped the FTT to 33 yards and the others to about 28 yards. So I can be sighted in about 5 yards further out with the higher scope. Obviously for really short ranges the high scope will shoot as much as an inch lower but that closes pretty quickly. With the slug HP, with the high scope it will shoot 1.66 inches low at 5 (vs. .74 with low), .87 low at 10 (versus .19), .29 low at 15 (vs. .14 high) and .08 high at 20 (versus .26 high). So by 15 or 16 yards, the high scope is not an issue but less than that the gun will definitely shoot significantly lower. So if I can get a longer sight in distance with a high scope why do I want them low?
I have the same thing going on with a Huben I bought (and really like). All of my "regular" rifles have a scope height of 1.6-1.7", and the Huben is running about 2.6" to shoot comfortably.It really isn't a problem, but since they all shoot around the same speed, it makes for a very different experience for holding off on dots. I'm second guessing everything with it that way . . .
So if I can get a longer sight in distance with a high scope why do I want them low?
Quote from: JimD on October 24, 2021, 05:44:02 PMSo if I can get a longer sight in distance with a high scope why do I want them low? Two very good primary reasons for wanting them low. One would be personal preferences with regard to fit and getting a good cheek weld, which is veryi mportant to achieve the best most consistent sight picture.The other, is to minimize the effects of cant when shooting offhand. A .5 degree cant may not sound like a whole lot, and the higher the scopes midline is from the bore line the more it's amplified. So, while that .5 degree cant on a gun with the scope mounted 1.5" high might put you half an inch off your mark, a scope mounted 3 inches will put you a whole inch off your target.
A high scope will give a much more pronounced high bell trajectory,..well suited for longer shots and known ranges.the lower the scope the flatter the bell trajectory will be,...well suited for quick shots at unknown ranges up to pretty close in,....downside is that after the 2nd zero ( that will be much closer than the 2nd zero in a high scope ) trajectory will fall pretty good.