this has always been an issue with many dianas. i am scoping a 46 and this is what i experienced. first the mounts. i used a 11 mm to weaver base and weaver rings (low). i first zeroed the scope by bottoming out the clicks and then counting back per the manufacturers instructions. that happens to be 200 clicks back on a hawke 4x16x50. with the reticle zeroed and the scope reasonably leveled side to side I shot at a spot on a grid at 15 feet.
the hits were 2 1/2 " low and almost verticle below the aim point.
i removed the scope from the mounts and cut a .015 shim from plastic that the mounts came in. placed in rear mount ring. put it all back together and cinched it down again carefully. point of impact was now 1 1/4 low and just about exactly verticle side to side. no click adjustments yet. a .015 shim was good for a whole inch at 5 yards. that calculates out to 2" at 10 yards and
4" at 20 yards. that is not a great deal of droop compensation but actually
pretty significant in light of not using any of the elevation adjustment.
considering that scope hight is close to 2" that is pretty close as a starting point. at the muzzle you would expect the point of impact to be 2" below the point of aim. you would expect some rise at 15 feet and at 1.25" that is what i have. this scope should have no troube with a proper zero for field target work. especially with 200 clicks available. at 1/4 minute of angle 8 clicks equals 1" at 50 yards and 200 /8= 25" of available elevation at 50 yards. my trajectory isn't that loopy. i am withing a few clicks of being centered side to side. i chose the 11mm to weaver adapter because i wanted to be able to move this scope to the diana 52 with the UTG droop compensating weaver rail and the same low rings if i ever want to do that.
That plastic shim under the scope at the rear scope mount approach has worked well for me.
If you get to the UTG droop mount, make sure your rings have a rectangular stop piece (I use B-Square interlock mounts). The Leapers Weaver mounts use the mounting screw as the stop and it is a round stop mating at the top of a square peg. With at gun with some kick, it will round off the peg at the top - ask me how I know.....
Hey Larry, I've been working at mounting a 4-16X50 scope on my D-54/.177. When I first mounted it, I shot some 7.9g at 75'. It was high and to the left by about 3" at 1073fps. Then some 10.5g which was dead on for elevation, 3" to the left at 875.6fps with a 1/2" group. Then some 11.5g which was 3" low and to the left at 815.6fps. The 7.9g and the 11.5g had about a 2-2 1/2" group. So the 10.5g was the best for group and speed and no compensatory mount. The speed and weight have a lot to do with whether it needs a droop mount or not. Have a great day - Lee
i used the utg droop compensator (leapers) and the space age rings with square stops. did not use any shims on the 52. i did not touch the windage or elevation on the scope since i set it set on the 46. in my office range i am
exactly 1" low and dead center on a verticle grid line. my ballistics program tells me that i should be 1.42" low in order to be "on" at 25 yards (ideal FT sighting in range in my opinion since that is the apex of the trajectory). this means that this gun will shoot high at 25 but within the adjustemnt range of the elevation adjustment with lots to spare. being perfectly in line with no windage is encouraging.
i may add a thin shim to the front ring to reduce the droop compensation since it does not seem to need as much on the 52 as on my 46. this seems to mirror my experience with the beeman/williams peep sight when i had mounted it on
both rifles. i needed more elevation on the 46 to bring it up. my 46 has more droop than my 52.
now i just need to shoot some to decide which rifle is going to be my primary
FT gun. it will come down to final accuracy. the 46 is not quite as strong a shooter as the 52. i will be putting a maccari GRT kit with delrin guides and tophat tonight. his guide is a perfect fit. tighter than the stock guide so should be smoother all around.
pelleteer (occasionaly posts here ) has been a great help in resolving the breach seal issues i was having on the 46. we used a .005 steel shim on each seal and two new square cut o ring seals that he sent me. no leaks.
i promised myself that i would not use a scope in FT till i was shooting 30% with iron sights. i missed that by 1 this last match (my third in 40 yeas). maybe next match i will make it and then its scope time from then on. doing this with iron is tough. no clicks and no rangefinding. its all ZEN.
First - don't beat yourself up. I just started FT last year, but I've never shot a match without a scope. I think it's different enough that you're just wasting time. Second - may or may not apply, but the best $70 I've spent in airgunning (remember I've only been at it a year or so) was to buy a Beeman one-piece adjustable mount. I can mount anything on my RWS 52 and know it will stay there - that mount is a BRICK. I'll never use anything else on a magnum springer.
I'm almost sorry I went to the UTG mount on the 460. I did it to head off problems that I never had with my Leapers one piece mount and a plastic shim between the rear mount and the scope. I may yet go back if my B-Square rings with blue lock tite loosen up!
On the 46 breech seal issue, I was amazed the other day when I looked at how my 300r is built. It does 820 fps and my 46's do 800 fps with cpl's. That means that the metal on metal "seal" on the cylinder to barrel is more efficient than the 46 "tube" with two breech seals. The "tube" is roughly twice the length of the 300r cylinder!
PS - Larry you should go with a scope on the FT thing. You would probably do a 12 power or less and not adjust the clicks, so you could hardly call that cheating on yourself! Sort of a hunter class with a springer.