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Rapid Ranging Scopes

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sscoyote View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sscoyote Quote  Post ReplyReply Direct Link To This Post Posted: July/27/2009 at 01:12
Now if u wanna' get super-accurate with it subtract the thickness of the line stadia to develop an even more accurate unit of subtension. Darrell Holland is starting to teach this in his long-range shooting classes, since most people tend to bracket between line stadia instead of from the center of the line to the center of the next line. Your 0.5" subtension unit would them be probably something like 0.45 or whatever Zeiss uses for a line thickness. May seem like splitting hairs but it doesn't take any more time to range with 0.5 or 0.45 once the simplified system is established.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sscoyote Quote  Post ReplyReply Direct Link To This Post Posted: July/27/2009 at 01:52

Sorry i can't edit here--bad computer i guess.

My AR that i use for coyotes is an ISSI .223 AI with a 9 twist Hart. I run 65 JLK Low Drags (BC=0.4) out of it at 3050 mv, and it SHOOTS with that bullet. What i did was i got ahold of an old DPMS VLD magazine that allows me to shoot the VLD's (and LD's) with a 0.25" longer seating depth. It really is a cool little gizmo. But if u try to get 1 u'll also need to get the VLD bolt stop and change them out. That 65 Low Drag at that velocity oughtta' be fairly close to the 75 A-Max out to 500-600 yds. or so, and will be a bit flatter at the closer ranges. As far as i can tell it give the best bang for the buck to about 500 yds. or so.

 
What is your load 2T?
Steve
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: July/27/2009 at 09:13
any type of reticle ranging will give you an error spread about 5% x the distance ranged. Since your target is 12" the cone of fire for the 223 about 5" will be inside that. Also I take it that you are not dealing with movers, so the biggest devil will be the wind past 300 yds. Also I am assuming you are shooting against the clock and not par time (given amt. of shots in stated time). If you choose a ffp it will allow you the same windage lead at any power if you choose a z6 or z8 reticle it has the windage built into the reticle and since your choosing an sfp in the lower range, the poi shift with change in magnification will be very small. The ballistic curve for 223  will give you about 10 moa or 2.8-3 mils at 500 yds. It is unlikely that the zeiss computer program will give the hold overs in even numbers at 9 power more likely somethinglike 7.5. as it is unlikely the distances will be at even numbers, which means you will either have to dial with either system or use hold over. Most of this is discussing the differences, the important part here is if you know how to shoot a spotter. If your not limited to the number of shots you chould shoot a spotter for each distance, and with an ar it can be done far faster than corrections can be dialed in. A best "gammer" plan would be to laser range the two longest targets and adjust accordingly, if the shoot involves money or a prize table somebody has already beat you to it.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Jon A Quote  Post ReplyReply Direct Link To This Post Posted: July/27/2009 at 14:32
Originally posted by 2Tonic 2Tonic wrote:

Concerning that table of size vs. range, does a FFP 9x scope have enough magnification to discern whether a target at 500~600yds is subtending .6 or.7 of a mil?  Or is it really just a judgement call, recognizing that you're only going to be off by 20yds or so and will probably still hit the target?

With enough practice, yes.  But it's certainly not going to be as accurate as can be done with a higher power scope.  I also feel reticles with 1/2 Mil hashmarks are helpful but with practice you can make due with the standard Mildot.  Now down to .05 Mil....that's getting pretty tough with a 9X, especially when you're on the clock. 

The good thing for you is the target is pretty large relative to the distance so for most of them a "judgement call" will be enough.  Without taking any time to actually "mil" the targets you'll just visually see the close ones as being between 1 and 2 mils and you'll just "know" how far they are--well enough to hit them, anyway.  Once they're noticably less than a mil you'll want to take more time and try and be precise.  But even then with a standard mildot you'll sort of be "eyeballing" how much space the target takes up between dots--1/2 way?  60%?  3/4?  Some get very good at that with practice and actually find it somewhat simpler/easier/faster than trying to worry about hash marks.  I haven't seen this reticle yet but assuming the dots are .2 mil diameter, remember that can give you very precise breakdown from 1.2 to .8, then .7 is 1/2 a dot away from one, .6 is 1/2 a dot away from both it's between, etc. 

If there's any way to set plates up at various distances and practice before the match it would be very helpful.  Even if you need to take the scope off the rifle so you can do it in populated areas, put the scope on a tripod.

As for holding or dialing, you might want to do both.  It's pretty silly to be dialing for 200 or 300 yd shots, that will just slow you down.  It will depend upon your load, but it should be easy to dial the turret to somewhere around 300 yds, then you'd hold about 1 mil low for the 200 yd shots, right on for the 300 yd and around a mil high for the 400 yd shots, fudging in between ranges.  Again, the actual amount will depend upon your load.  But the target size relative to distance gives you some wiggle room so it doesn't need to be perfectly exact.  That would allow you to take care of all targets out to that distance without even moving from the shooting position or taking your eye out of the scope.

For the 500-600 yd shots, you'll want to be more exact.  First in ranging them, and then in firing.  With a 223, even with a heavy, high BC bullet, wind drift gets pretty substantial at those ranges.  It's difficult to hold both elevation and a large amount of windage precisely with a standard Mildot with the target hanging out in space.  This is where a ballistic reticle with lines has an advantage.  For this reason alone (unless you had a nice windless day!) I'd be inclined to dial elevation for the far shots so you can accurately hold wind while keeping your elevation cutting the target in half.

For that last reason a reticle with lines can have an advantage in shooting speed.  The problem is finding one in your pricerange that matches your load well enough, then figuring out how to range with it (which certainly can be done) and you're pretty much stuck with one power.  All those problems can be delt with, it just takes some effort.  The chances of messing up under pressure (using the reticle on the wrong power, etc) are probably higher.  The FFP Mildot is more versatile as it will work with any load, distance, target size, on any power, etc, but if you got everything worked out with one of the rapid reticles and didn't mind shooting the whole match on one power it could certainly be fast.  The JP reticle in my ACOG is fantastic for stuff like this shooting speed-wise, but I'm stuck with 4X and I haven't even tried ranging anything with it...but I definately see how both styles could work.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sscoyote Quote  Post ReplyReply Direct Link To This Post Posted: July/28/2009 at 02:03
When i set up a reticle for downrange zeroing i employ the same method Jon has done above for mil-dot rangefinding. If i were using that reticle i would find out what the stadia points all subtend (Zeiss should be able to send that info to u) at the optics highest power. I'd then calculate a conservative point blank range zero for a 9" tgt. (3/4ths of actual tgt. size maximum). I'd then calculate my zeros in 25 or 50-yd. intervals, BEYOND MPBR. I.e. if bullet drop is 13 MOA at some given distance, and say the 3rd stadia line is 10 MOA and 4th stadia line is 14 MOA, then the hold for 13 MOA is 3.8 (3rd stadia and 8 tenths down to the 4th stadia line). Since there are 4 MOA between that stadia to stadia gap, then 3/4=0.8 rounded off. Same with 10 mph windage for the horizontal stadia points. This way a grid system is calculated for the reticle. Once tested, and troubleshot, it then all goes into a sticker and placed in the Butler Creek scope cap cover, just like this--
 
425-2.4-0.9
 
...obviously range, elevation and windage, always in that order, no headers needed. The system is exactly this, no deviations. I don't worry if the reticle is intuitive or not as the Butler Creek reference system is almost as fast as the intuitive system anyway. Fact is, I may not even know what a particular stadia point's zero actually is in the field, as IMO the stadia r only there to calculate interpolation and test trajectory vs. subtension. 
 
The only problem with using the system Zeiss computes by changing the magnification is that u now have to keep adjusting power back and forth for rangefinding and downrange zeroing, and that's probably not gonna work. Rangefinding is plotted the same as Jon posted above for a subtension unit of 0.5 IPHY placed in the Butler Creek Blizzard-style scope cap cover noted above in 1 of my previous posts, but it only starts beyond the MPBR rangefinding system noted above. It's not necessary for closer ranges. A range sticker should always follow the "conservation of information" concept to minimize confusion.
Steve
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 2Tonic Quote  Post ReplyReply Direct Link To This Post Posted: July/30/2009 at 03:42
Wow, where to start?!?!  SS, DC, and Jon A; you guys have set my head to spinning! Whacko

First, thanks for the solid info, it's much appreciated.  Second, let me sift through the dusty reaches of my brain and try to come up with an intelligent response!

SS, my current load is either a 77gr Sierra Match King BTHP over 23.5grs of Ramshot TAC, good for 2800fps thru a 1 in 8 twist 20" barrel, or a 75gr Hornady ( A-Max or BTHP Match, both give their BC as 0.395) over 23.6grs of TAC which clocks at 2790fps. Both these loads perform almost identically to the Hornady 75gr TAP factory load, which I also use to benchmark my loads.

As for the ranging system you're talking about , I follow you on the math in the example,         ( btw, brain fade, IPHY is inches per....hash........?) and I can see how one could build a detailed and accurate chart using that system. 

However, the one big fly in my ointment there is brought up in Dales' post.  In order for the holdover bars to be accurate for my load the Zeiss computer says I must set the scope to 6.76x!  Yes, it could be found mathematically, or possibly even by measuring thru the scope, or perhaps better yet go shoot at paper at exactly 300,400,500 and 600yds until you fudge up the setting which allows the HO bars to zero those shots. But even if you can dial in to 6.76 and scribe a reference line on the scope it would seem a tall order to zoom to 9x to range and then re-align to 6.76 accurately and repeatedly while on the clock!  I suppose I could go and range 12" targets set up at specific distances, say every 50yds out to 600 with the scope at 6.76 ( or whatever power proves to sync up the holdover) and create a data chart  and just shoot the match at  that fixed power, but lets agree that this could prove less than.....elegant.

 Add to that the fact that ,no, you cannot shoot spotter rounds.  Every round over thirty results in a penalty.  The competitors do not get to see the target placement until it is their turn to shoot.  The firing line is over a rise from the check-in/staging area and access to the range is restricted.  You don't even get to watch the other shooters, you just count their rounds and the timing tells you when they're hunting for a target.  As I posted earlier, when you hit the firing line you can only see 10 ~ 12 of the targets from the first firing position.  The rest only come into view when you change firing locations and the targets are moved radically every week. I've watched 4 of these events ( non-competitors, i.e.spectators...ahem... can watch from an elevated platform that gives an overall good view down all three branches of the canyon) and it looks deliciously grueling, guys in and out of their scopes so rythmically they look like Stevie Wonder.  Whistling

I'm not sure which avenue to pursue yet, ffp-mildot or sfp-rapid Z, but at least now i'm looking at two good pieces of glass.  Thank you guys for your continued input, as I'm sure I'll be picking your brains some more before I purchase.  Later

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: July/30/2009 at 08:27

the match then is a par course, either fixed in round count or must be completed in a certain length of time. The course designers have done this to off set the advantages of a semi auto and since there is no power factor the course favors a small caliber and weapon with fast recovery.. increases in scope magnification of sfp scopes will cause a change in poa that makes the shooter readjust the cross hair which gives a lower point of impact. with the load you are using and only shooting to around 500 yds the z reticle will give you maybe 6 inches difference between the lowest power setting and the highest. In other words if you are center of impact at 500 on 6 power just hold on top of the metal at 9 power and you will be within the cone of fire. This type of course is best shot with something like a 204 ruger or 220 swift around 4000 fps which have moa drops around 4 moa at 500 and can be zeroed at 300 yds. This means no dial is needed for any distance and small if any reticle hold over or under.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote BeltFed Quote  Post ReplyReply Direct Link To This Post Posted: July/30/2009 at 10:32
Very interesting match 2Tonic. Where in Indiana is it, and is it an open match, or members only?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 2Tonic Quote  Post ReplyReply Direct Link To This Post Posted: August/03/2009 at 00:11
DC, I'm not quite sure if I follow you completely. Are you saying that once I find the power setting that actually makes the holdover points on the reticle correspond with the point of impact at the indicated ranges (3,4,5,600yds) I could dial back up to 9x for accurate ranging and just hold the holdover point high on the plate? Is this just for the longer shots or does this p.o.i. shift occur at all ranges? Or again, am I better off having found that magical power setting .......
(6.76 according to Zeiss....can't figure why they would'nt carry it to 4 decimal placesHammer...) to go range targets of known size and range to chart their appearance against the hashmarks at that power? Can the average person clearly see a 12" plate at 600yds at 6~7x?

BTW, it's not really a "par"match as there is no fixed time or round count, simply your time to solve the situations is your score plus penalties for targets you either don't engage, or miss and expend extra rounds at above the minimum thirty.

Beltfed...these matches are up here in NW In. near a tiny town named Belshaw.  The range is on a ranchers private property that butts up against an abandoned quarry (limestone, I think). Last year he got the chance to buy a chunk of the land and its a great range after a lot of backfilling, sort of like three box canyons that all meet.

Right now all activity out there is invitation only, I don't know what kind of loopholes he'd have to jump thru to go public, or even if the owner wants that much action what with his livestock and all.  He host these "matches" on a rather informal basis, in fact the participants all chip in to pay his kids to set the targets and paint them after every couple of shooters. The guys who came up with the rules are all buds who are into AR's and shoot together out at the DNR ranges around here, thats how I know some of them.  I got hooked up with this project because I was able to deliver the heavy earthmoving gear to reshape and and fill-in the quarry floor. (as a favor to my friend, for a favor to his friend, for a favor to the range owner...what is that 4 degrees of separation?)Call Me

So that got me a ticket to the circus, and hence my quest for information about putting a useful piece of glass on my rifle.

Thanks for the interest, and again I really appreciate all the info and opinions !!

2tonic
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: August/03/2009 at 09:23
the poa changes with different magnifications. this results in a poi change because the shooter moves the cross hair for correction. It easer to watch a sfp scope do this if you watch for holdover changes while making power changes. it really doesn't matter if you "calibrate" the zeiss to their internet site, as long as you under stand the principles that are going on and about how much shift is involved with each sfp in that magnification range. adecrease in mag. will raise the poi. in this case your only shooting to 500 yds, and the effect the shooter will see range of change in poi in a wide range variable (8x32) as opposed to low range variable (3x9) but the this doesn't have anything to do with the bullets ballistic characteristics. high velocity above 3500 fps even with low bc have about the same wind drift to 500 as a 308. a 12 in. target amost covers the full drop in a .223 round. and although high bc 223 are nice aren't really necessary as high velocity in these type of matchs. This course could be shot with a swift/22-250 with a 300 yd zero and a regular duplex reticle as all the targets are in the cone of fire at that range. Or in your case leaving the scope on the magical power.
Whether a shooter can see a target on low power and hit one on low power is two different things.
as to the course design--- this type of match is called "home townin". a group of shooters get together and work something up, based on their guns and the type of shooting they do. the most active usually develop the course of fire with unconsious insertions which will strongly favor certain types of (multiple choice)guns, targets, timed fire, reflections of reality,as opposed to a sanctioned course which goes before a commitee to weed out biases. Not saying this is bad, as long as everybody has fun and gets to shoot alot what the hey. Its unlikely this will go public because of liability problems, getting insurance to cover the accident that will happen (just a matter of when).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: August/03/2009 at 09:40
I ran the numbers at zeiss site and get closer to 8x for magnification in the .223 for both 50 vmax and 75.
But your comment on zeiss giving 4 decimal places or any at all raises a point I'd like to make about compensating reticles, scope makers and their on line computer programs that really upsets me.
The calibration marks on the powers of all variable scopes suck!!!!! The new zeiss conquest have the best markings as they give at least in 1/4 powers. No scopes have click stops. and the swaros (at least on mine) are only in whole powers. Soooo what good does it do to give someone information in fractions if the device doesn't calibrate to that. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: August/03/2009 at 09:42
sorry I got started-- but if thats not enough the "distance" between power settings on variables gets less as the mag gets higher, so 1/2 of a power becomes less critical to the scope the higher the mag. but is actually more important to the shooter than 1/2 power adjustment at a lower power.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sscoyote Quote  Post ReplyReply Direct Link To This Post Posted: August/04/2009 at 20:29

That's one of the reasons i like to stick to the optics highest power whenever i use a reticle for downrange zeroing or rangefinding. That (and the lowest power) are the only 2 stops on the power ring, and if the subtensions are accurate at the optics highest power, then i stick with it. Doesn't really make any difference whether they subtend as calibrated as long as i know them either via catalog spec. pg. or by measuring myself.

BTW, i looked at the Zeiss just this past wknd. at a gun shop, and the rangefinding marks are pretty coarse. I would subtract the line thickness if using my rangefinding system noted above.
 
One thing--find out how many guys r using a mil-dot reticle. If there's only a few then most of the other guys (if any of them really) will be able to get as accurate a range as u will by using the system i've detailed above, since they'd have to be an optics engineer to figure it out or get lucky like me and just stumble upon it.
 
Oh yeah almost forgot--IPHY is inches per hundred yds.


Edited by sscoyote - August/04/2009 at 20:32
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: August/05/2009 at 10:26
2tonic-- still not sure if you understand that ranging with a sfp can be done at any power, its just a ratio of the orginal setting on highest power.  ranging and holdover are not the same thing.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 2Tonic Quote  Post ReplyReply Direct Link To This Post Posted: August/10/2009 at 01:53
DC and SS, thanks once again for the skinny on ranging with sfp scopes!!

Please forgive my tardiness responding to you, I was on the road all week and am just now finding a few moments to sit and reply.  Glad you appreciated my sarcasm about the 6.76x.  It just struck me that maybe  a person could find 6.75x as that is 75% of full power but how the hell would you know if you tweaked it to 6.76 or not, so why not run it out to 4 decimal places and create a new hobby.  Wink

DC, I think I understand what you're getting at; if I set the Zeiss at 6.76 (whatever.....) it happens to be 75% of full power, therefore as long as I apply that multiplier (.75) to my ranging and create my crib notes based on that data ,I'm golden.

 i.e. at full power a 12" target at 300 yards will subtend 2 of Zeiss' ranging marks (representing 2" each). Using their formula of target size divided by ranging inches (in this case 4") equals range in hundreds of yards, we get 12/4 = 3 [x1oo yds]. If I now reduce power to 6.76x the target will appear smaller and only subtend 1.5 ranging marks giving me the data 12/3 = 4 [x1ooyds]. Now I apply the .75 multiplier and I get 300yds.

This can be done for any power percentage as long as you can consistently set the scope to that power setting. Then you just have to extrapolate the data for your particular situation.  Please tell me I'm on the right track with this?????

What I'm not sure I understand is the POI shift with magnification change.  Is this inherent to all sfp variable scopes? Is it caused by the scopes offset to the boreline or the reticle/erector not being centered in the tube?  Wait one.....are we talking a POI change at the zero range ,or just the holdover points which represent differing moa drops depending on power settings? If it's just the holdovers then I think I do get it.  Zeiss' ballistic program tells me to dial down because my load has more drop at long range than a lighter/faster load, more than compensated for by the reticles spacing.  So to sync up the POA/POI I dial back and the reticle covers more MOA. Is this the shift your speaking of?

Also, what load data did you enter in the Rapid Z calculator? I just tried the Hornady 75gr match load and the 75gr TAP and got 6.76 and 6.82 for optimum power. Did you set max power at 9x?  That brings me to another point you were making DC, about shooting with a .204 or other caliber.  That makes a lot of sense, but a .223 is what I have and with a 1 in 8 twist it works best with 62gr pills or bigger.  What about using a 300 yd zero?  Can you recommend a good online ballistic program where I could try my load info with different zero's?  Most that I've found, including the Zeiss, are stuck on either 100 or 200yd zero's.

BTW, SS when you said the ranging marks on the Rapid Z are coarse were you referring to the areas where they denote .5" between marks, or just the general thickness of the hashmarks.  I was actually having a problem getting the marks to stand out against a dark background ( some fenceposts running into a tree line) and wished they were somehow bolder or longer.  I wouldn't anticipate this problem on the range, but it does make one think fondly of illuminated reticles.......sigh.

At this point the Zeiss Conquest 3-9x40MC is looking more and more attractive.Zeiss has a $75 rebate going on them now and that gets me down to $425 as opposed to $599 for the SS Variable.  The concensus offered at this site is that they are both good pieces of glass and worthwhile investments. Anyone else care to chime in, please do.

Again, thanks for sharing your knowledge and patience with me,

Later,
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BretShooter Quote  Post ReplyReply Direct Link To This Post Posted: August/10/2009 at 13:42
First post, so sorry if I step on any toes, but what about the Shepherd line of scopes?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: August/10/2009 at 20:18

two ways to look at it-- your calculation method is correct, and so no need to go back to highest power each time.

the other way to look at it-- set your target at the range you wish, turn the power of the scope to fit the grid, make a small mark on the power ring. use multiple settings if you can keep it straight.
 
technically the poi doensn't change but the poa changes, the shooter recorrects to adjust so the poi then changes (chicken and egg question). How much depends on the power range of the scope the range of the shot and designer intent. Usually its not seen alot in scopes under 10 power unless they compensating reticles in them , then they effect is used to an advantage.
 
your explanation of the poi/poa shift is accurate and represents looking at the same problems-- no wait let me count them at least 4 different points of view. This is one of the confusing aspects of the whole business. A shooter will get hung up on one aspect when the problem can be looked at from many.
can't remember the load tried in zeiss
which brings up the 3rd method you could use. Run your data in jbm, noting the moa drops for the ranges which correspond to your reticle, (which are the same in the zeiss, but they don't tell you that), now correspond this data and it will give you the moa distance between the reticle spacings in particular scope your using.
this same technique can be used for a ffp mil type reticle, but why ----I'm glad you ask, if they are so much better
and -----  reset the outputs in JBM to give the drop in mil and read them directly off the reticle in the ffp scope. no need for any dial in.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 2Tonic Quote  Post ReplyReply Direct Link To This Post Posted: August/17/2009 at 01:51
DC, thanks for the heads-up on the ballistics calculator. It's proving quite entertaining!

I've run several loads through it and the numbers confirm a MPBR out to 280yds on a 12" target.  Using the "multiplier" we discussed before (.75) , such a target at 300yds will subtend 1.5 of the ranging hashmarks on the Zeiss reticle when set to 6.76x, or 3/4 power.  It will also, fortunately, subtend exactly the area between the horizontal crosshair and the 350yd holdover mark, so framing every target in the ranging marks isn't neccessary.
If I draw down on a target and it appears larger than this measure I can hold center with the crosshairs as it's within PBR. Only if the target appears the same or smaller will I have to range it to determine the proper holdover point.
I think this set-up will give me the best chance of ranging and firing quickly enough to be competetive, so I went ahead and bought the Zeiss Conquest 3-9x40. Now I'll have to go scan SWFA for a mount for it. The SS ssalt looks like the ticket.
Thanks again to all of you who offered your advice and opinions, and especially for the solid technical discussions. 

To the SS endorsers; you didn't lose one, I'm halfway through a build on a 6.5 Grendel and the SS sounds perfect for it. Maybe even one of the fixed power scopes.
p.s.- I went out this weekend to observe another match and noticed several shooters had added Aimpoint/red dot/heads-up type sights to their weapons, mounted either above the scope or canted at a 30~45degree angle.  Couldn't really tell if this was to their advantage for closer shots or if it slowed them down moving from one optic to the other.  Is this how "gaming" starts?
p.s.s.- Bretshooter, I don't have any experience with the Shepard scopes. I do know they have a reticle in both the first and second focal plane, that's how the "one shot zero" is able to work. As far as quality of glass....no idea, but that scope uses circles that correspond to an 18" target for ranging and that would make it difficult to use for my application where I need to precisely range 12" targets. Thanx anyway for the input.

Later
2tonic
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: August/17/2009 at 08:08

dots are added to the scopes in 3 gun matchs because one or more of the stages may require firing thru a port at a very close target. 5 to 50 yds. and many times the width of port will block the optical site visibility and the gun must be laid on the side or a dot put on the side to see the target, also the 2 inch mounting on an ar will cause the shot to hit high at this close of a range, and a lot of times a no shoot (hostage) is placed there for penalty. Yes this is how gaming starts.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote BretShooter Quote  Post ReplyReply Direct Link To This Post Posted: August/19/2009 at 15:41
Yeah, I wasn't thinking of the one shot zero faeture.  But they also have a reticle for 24" circle.  so range to the circle that fits, then shoot half the distance up the scale.  What weight does speed have in this event?
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