Scopes+edgun elevation range?
Hi all,
Is it common to run close to the limit of downward clicks on the elevation (vertical) knob? I was sighting in my r3 and I almost bottomed out on the clicks. I got the target on my crosshairs at 25 yards. Fortunately, my scope has mildots. It’s not a huge deal. I’m just curious if this has happened to a y of you.
Thanks,
Gabe g
All Replies
It really depends on the height of your scope rings…
I had thought he needed to lower the height but after putting everything in Chairgun (basically a trajectory model)ing tool without firing the rifle) I found that another 1/2″ (13mm) of height would actually reduce the total number of clicks.
So I would imagine that too low of scope rings that are canted might not help out the total number of clicks overall…
For the 25 in the Chairgun test above the total drop of the projectile at 100 yards was only 12″, which is not very extreme and would tell me serious canting of the scope is not required if the proper height of scope rings is used.
Burris advertises this :
“Swapping the standard inserts with a pair of offset inserts will move the point of impact approximately 5″ at 100 yards for the .005 inserts, 10″ for the .010 and 20″ for the .020.”
I took that for granted and even tho they don’t use the term MOA, the formula equals an MOA.
I did not know the Matador has a elevated base and I hope you are wright.
When I first installed the scope on my R3 I used 30mm Burris Signature Zee rings with the +/- .010 on both rings also. I was 15 clicks away from my optical center on the 50 yard zero. At first I was happy with that, but then I begun to reach close to the end of adjustments when I tried to shoot 100 yards and beyond, not to mention the view quality was cut at least in half because of the zoom and extreme internal adjustments. In my current setup I’m very close to optical center on the 100 yard range and the view quality is very good even tho I’m maxed out on zoom. On 50 yards and below I can also see good because I use the minimum zoom. I’m happy again. So for me, Ed’s canted base and both inserts were not enough.
I guess every scope is different and you don’t necessarily need both or any of the canted inserts at all. Also, every gun shoots at different speed so the numbers/formulas differ from user to user. Everybody should test and adjust both of them until they are satisfied for the purpose and the range of the gun.
The entire post has very good info, especially this sentence. Alow me to add that you can adjust the off widage as well with this inserts but you will proportionally lose some elevation value.
Gabe, all these guys are right. But that’s a LOT of info above.
Yes, we all have dealt with this problem in the past.
This scope correction used to be a real problem with the old springers, due to the slightly down-sloped barrels used then.
The answer in simple terms…lower the scope, or simply cut a few black electrical tape “shims” for the bottom of the back scope mount. That will give you the few thousandths of rear scope elevation you need to even out your elevation adjustment.
Eduard has mentioned he is putting a few mm’s of downward correction on his new scope mounts to accomodate for this little problem.
And it is really a small problem, easily resolved, and once corrected, it never has to be addressed again unless you change scopes.
Fix it quickly, start shooting, and have fun. That’s what counts.
Regards,
H 😯 😯 T
Hi Syn and Kiba,
thanks for detail info!!
I need to take small bites to digest it..
I’ll try to get some data as I can, which might be awhile.. and post it..
cool!!
Gabe G.
I love this forum 😆
(mine too) 😉
😆 😆 😆
Ed made the scope rails of the R3s with some built in cant so your scope should be biased towards the bottom half of its elevation adjustment at “normal” zero ranges. Running near the bottom of your scopes elevation adjustment at your zero range is a benefit IMO– it gives you more available up elevation adjustment travel which is needed for longer range shots. Unfortunately depending on your scope you might run into trouble as some scopes start having optical issues/distortion near their adjustment extremes or if your scope has limited elevation travel you might run out of adjustment range before you can get the reticle to match your point of impact at your desired zero range.
When I first installed the scope on my R3 I used 30mm Burris Signature Zee rings with the +/- .010 inserts setup for extra cant as I did on my R2.5. When zeroing the rifle the scope ran out of elevation travel trying to set a 50Y zero– I forgot the R3 has cant machined into the scope rail and had too much cant in the system between the canted rail plus the additional cant in the offset ring inserts. I went back to the 0-offset inserts in the rings and now have 4 mils down / 17 mils up elevation remaining in the scope at a 50Y zero which is perfect for “reaching out” on long range shots.
With the canted rail on the new R3 the issue some might have is trying to zero a scope with limited internal adjustment range. Based off my R3 if your scope has less than 14 mils (~51MOA) of elevation travel you might not be able to achieve a 50Y zero without resorting to adjustable scope rings like Burris Signature Zees. Shimming the scope if using straight rings isn’t a good choice because then you induce stress in both the scope tube and the mounting rail on the rifle.
The 0, 10, and 20 marks on the Signature Zee inserts aren’t MOA of offset but rather the difference in ring thickness in thousanths of an inch (the “10” rings are .010 thicker/thinner, the “20” rings are .020 thicker/thinner); the actual change in point of impact is then a function of insert thickness and distance between the rings.
If you run the numbers at 5″ between ring centers:
.010 up offset in the back ring and .010 down offset in front ring will shift the point of impact 7.2″ @ 50 Y / 14.4″ @ 100Y (approx 14.5 MOA.) This is the max adjustment capable with the 30mm rings as Burris only makes .010 offset inserts for the 30mm rings.
With the 1″ rings you can use .020 offset inserts; if you use .020 up offset in the back ring and .020 down offset in front ring will shift the point of impact 14.4″ @ 50 Y / 28.8″ @ 100Y (approx 29 MOA.)
You can also run combinations of a 0 offset insert in one ring and .010 or .020 inserts in one ring for a partial change.
Mounting the rings closer together will increase the effective scope cant, moving the rings farther apart will reduce the effective scope cant.
Example using the +/- .010 inserts at different ring centers:
4″ ring centers: 9″ change @ 50Y
5″ ring centers: 7.2″ change @ 50Y
6″ ring centers: 6″ change @ 50Y
Ok, so I got some preliminary numbers. You are looking at about 120 clicks from 25-100 yards.
I guessed you have 1/8″ clicks at 100 yards? Also what does the turret have in terms of numbers, my Accushit goes from 0-9 in one rotation with 8 clicks in between for a total of 72 clicks in a rotation. My Nikko goes from 0-7.4 or 60 clicks in one rotation.
Now here is the strange part.
Have you reset the zero on your elevation turret?
And can you do a test for me?
Test: I am trying to find two things. The natural zero for the scope in terms of turret rotations and shot placement (in yards) at the scope’s optical center.
Turret center. Turn the turret to full up and count the rotations to full down (probably somewhere between four or five complete rotations). Count the rotations, divide by two and then return the turret to the center of it’s travel to the nearest two to four clicks.
Shot placement: Go outside and shoot at different distances (by moving your target from closer to further away) until your point of impact is at the point of aim and write it down. In other words your pellet will impact the cross hair point somewhere between 25-75 yards without clicking the scope elevation turret after it has been optically zeroed, I need the distance at which this happens.
Why is this important? In Chairgun you set the zero point and it gives you clicks at the different distances.
If your rifle shoots at a ‘natural’ (optically centered reticle) zero at 75 yards you will need -63 clicks at 25 yards and 58 clicks at 100 yards.
If the rifle shoots at a ‘natural’ (optically centered reticle) zero at 50 yards you will need -19 clicks at 25 yards and 103 clicks at 100 yards.
If the rifle shoots at a ‘natural’ (optically centered reticle) zero at 35 yards you will need -2 clicks at 25 yards and 121 at 100 yards.
What I have also observed is that if you add 0.5″ to your scope height you will actually reduce the amount of clicks needed to shoot from 25-100 yards (from 120 to 105)! Granted this will not make you cheek weld much better and it will make the poi change greater if the rifle is canted when firing.
Chairgun info for reference:
Pellet Caliber: 0.25″
Pellet weight: 25.4 grains
Pellet BC: 0.0370
Pellet Velocity: 908 fps
BC tol: 10%
MV Tol: 1%
Clicks/Moa: 8.377 (1/8″)
Scope Height: 1.969″ (50mm/1.9685″)
1. Scope height above barrel, or the following.
a. Barrel outside diameter (shroud)
b. scope outside diameter at muzzle end and
c. it’s height above the barrel (shroud).
2. Pellet weight
3. Pellet name (so I can get the BC)
4. Pellet velocity
5. Overall shooting range (for example 25-150 yards) and output intervals for click readings (every yard, every five yards, every ten yards).
Hi Syn,
Here the infor
shroud diameter- 25mm
scope objective diameter- 53mm
scope height above shroud- 11mm
Pellet weight- 25.4 grains
pellet name- JSB .25cal Kings
range- 25 yrds -100yrds every five yrds.
thanks Dude!!
Gabe G.
Ok,
It all started as an experiment.I needed the bell of the scope lowered so I can be close to the optical center at long distances and also to increase the number of useable clicks in elevation. I have 10MOA insertions X2 = 20MOA of elevation but I need around 40MOA in total.
I started with electrical tape as I thought I need to experiment with some type of soft malleable plastic, so I will not damage the scope. First I put just one layer but there was a too small difference so then I put 4 layers on each half of the rings. Logically the diameter of the ring changed. It was no longer 30mm and the scope didn’t fit the rings anymore.
Striped the electrical tape off and then put one layer just a little smaller than the half of the ring, then another layer a little smaller than the first one, and so on until the 4’th layer was just 1cm long on the center of the half. That did made a difference and it wasn’t too much stress on the scope. I just need it to see how it worked and it was supposed to be taken off after that but the purpose was met and the groups were the same so the scope does not move in the rings so I let the rings/scope as it was.I know it is kind of stupid but at least I’m honest.
I have those rings about a year now, and I know there were available long before I got them. I really don’t understand how long it will take Burris to make 20MOA insertions for the 30mm scopes. They only have the 0 elevation and the 10 elevation , but the 1″ rings have the 0 , 5 , 10 and 20 MOA insertions and the 1″scopes are slowly disappear from the market as the 30mm ones are a lot superior. Go figure.
Eventually I will get something from this list but I will have to get used to the idea of the price and the scope being to high.
http://www.midwayusa.com/find?userSearchQuery=riser+moa
Maybe Ed will begin to send the guns with a 20MOA base straight from the factory.
aluminium doesn´t compress under pressure as electrical or paper tape, even the black stripe that´s comes with the mounts…
I dont understand what for you use over the scope
(sorry for my english, i´m a little rusty) 😉
go to full right, count turns to left, could be 7 turns, go 3,5 or to YOUR scope half, same for elevation and… thats all.
Or you can use a more precise method :
I have Burris Signature 20MOA elevation but it was not enough for a 100 meters, close to optical center view, so I used 4 layers of electrical tape on the upper half of the front ring and 4 on the lower half of the rear ring. Red Bull does’nt seem to be a bad idea. Maybe I will try it if ever unmount the scope from thr rings. I really wish I had a very slim 20-40 MOA rail…
Thanks. Will try it.
Gabe
if you need more high regulation, (for longer shots), you can add a few aluminium stripes under your scope, (rear mounting), i´m using 5 aluminium soda can, Light Coke BTW, but RedBull serves as well… 😆 😆 😆 ).
Only 5 stripes can solve your problem, test with 4. Only over the lower scope ring half of course, between the moun ant the scope. Allways start with the scope knobs in the Optical center.
go to full right, count turns to left, could be 7 turns, go 3,5 or to YOUR scope half, same for elevation and… thats all.
seeyou, good shots! 😉
I’ll get that info posted ASAP.
Thanks!
Gabe
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I had thought he needed to lower the height but after putting everything in Chairgun (basically a trajectory model)ing tool without firing the rifle) I found that another 1/2″ (13mm) of height would actually reduce the total number of clicks.
So I would imagine that too low of scope rings that are canted might not help out the total number of clicks overall…
For the 25 in the Chairgun test above the total drop of the projectile at 100 yards was only 12″, which is not very extreme and would tell me serious canting of the scope is not required if the proper height of scope rings is used.
I must admit I didn’t know that.
Another good piece of info. If everybody would share they’re testing and thoughts we will cut a good percentage of trial and error that will save time and money. Nice work you guys !