BDC or CDS system??
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ImBillT
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I either use 200yds or as far as I can go without being more than 2.5” high at the peak depending on the gun. In my .260AAR I go with dead on for shots under 300, and top of the back out to 400yds. I use a simple duplex almost exclusively, but have considered a move toward some the Christmas tree type MOA reticles.
On most scopes you can find out how many MOA are between he crosshair and where the duplex gets thicker at different powers. You can use this for holdover as well.
Guy
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I like that simple approach. With decent loads, your 7mm magnum is a pretty flat-shooting cartridge. With your self-imposed limit of 400 yards (which I think is terrific) you really won't ever have to hold above the elk to take it. I've made some 300 - 400 yard shots simply holding right on the back of the animal, letting that bullet drop nicely into the vitals.
Consider doing some off-season coyote hunting with the same rifle and load, you'll get those 200, 300, 400 yard shots down pat!
Regards, Guy
Boarmaster
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This is very good and practical advise. Especially if your in wide open coyote country. If not then just shooting off season at those ranges would be good.
Well, I've been convinced. Just pulled the trigger on the VX-3i 3.5-10 with the standard duplex reticle. Cabela's has them on sale for $320 and I had a $50 gift card so it ended up being a pretty sweet buy. I plan to hit the range more this year than I have in the past and definitely figure out exactly where my bullet is hitting at certain ranges. I was thinking about it and in the past few seasons I haven't shot at a critter that was more than 250 yards away. Once again, thanks for all the input. Can't wait to get it mounted up and into the field!
MinnesotaHunter
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I have used both and most of the comments above are accurate, some of this is repetitive, but here is my take based on using both. Full disclosure, my duty rifle has a Trijicon ACOG with a graduated reticle that I have been using extensively for 15 years, and for me it is very effective.
BDC:
- unless you invest in an FFP scope the graduations are only accurate at a specific magnification setting.
- adds clutter to your sight picture.
+ improves accuracy of holdover; it is just a reference point.
+ Less opportunity for loss of zero, or zero creep due to repeated or accidental adjustment.
+ Faster
CDS:
- opportunity for zero shift or tracking issues due to malfunction or inadvertent adjustment
- Slower
+ uncluttered sight picture that allows dead hold.
+ Accurate at all power levels
IMO, neither of these alone equip you to shoot beyond 400-500 yds, as neither address the issue of wind; which in most circumstances is a far greater margin for error than range correction. I think they are personal preference with the exception of preventing the turret from accidentally turning, and I am not convinced of the reliability of their tracking after repeated dialing.
As for BDC reticles spend the time and get the precise yardages for your given optic/cartridge. The graduations in those scopes are generalizations based on a close fit for the masses. For example, I have a 7mm Mag with a Zeiss Rapid-Z reticle; with my chosen load the 400 yard line actually represents 427 yds.
That being said, I own 3 CDS scopes and have not had an issue with RTZ. I did have an issue with a turret accidentally spinning on a Vortex HSLR, and it cost me a nice Mule Deer I had been chasing for days. Now I wrap a piece of electric tape around the dial to keep it from spinning. If I buy another CDS scope it will have the Zero Lock that comes on the VX-5/6.
BDC:
- unless you invest in an FFP scope the graduations are only accurate at a specific magnification setting.
- adds clutter to your sight picture.
+ improves accuracy of holdover; it is just a reference point.
+ Less opportunity for loss of zero, or zero creep due to repeated or accidental adjustment.
+ Faster
CDS:
- opportunity for zero shift or tracking issues due to malfunction or inadvertent adjustment
- Slower
+ uncluttered sight picture that allows dead hold.
+ Accurate at all power levels
IMO, neither of these alone equip you to shoot beyond 400-500 yds, as neither address the issue of wind; which in most circumstances is a far greater margin for error than range correction. I think they are personal preference with the exception of preventing the turret from accidentally turning, and I am not convinced of the reliability of their tracking after repeated dialing.
As for BDC reticles spend the time and get the precise yardages for your given optic/cartridge. The graduations in those scopes are generalizations based on a close fit for the masses. For example, I have a 7mm Mag with a Zeiss Rapid-Z reticle; with my chosen load the 400 yard line actually represents 427 yds.
That being said, I own 3 CDS scopes and have not had an issue with RTZ. I did have an issue with a turret accidentally spinning on a Vortex HSLR, and it cost me a nice Mule Deer I had been chasing for days. Now I wrap a piece of electric tape around the dial to keep it from spinning. If I buy another CDS scope it will have the Zero Lock that comes on the VX-5/6.
sbhooper
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I totally agree with this. Knowing the ballistics of your load and lots of practice will easily cover everything out to 400. If one uses a bdc, it necessitates shooting at different ranges to see where the lines actually match the range. Most are relatively close. I have one that is pretty close, but I also ran tests to get the exact ranges.
I also have SWFA scopes, where I can twist turrets. They are great, but rarely do I have shots past 300 anyway, so they are pretty much set and forget. I have only used them a few times and they worked perfectly. Leupold and Vortex CDS-type systems are having lots of failures to rtz and track. The bottom line is, that with a scope used to spin turrets, moving parts are more apt to add a certain degree of failure to the equation.
ImBillT
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^^^ Totally agree. I just use a duplex, sight-in at 200yds, hold top of the back at 400yds. I spent a lot of time shooting HBR, then moved to F-TR before I decided that I’d rather hunt than shoot matches. Anyway, the majority of match shooters in those two disciplines, unless something has changed, don’t touch a knob once they start shooting for record. They adjust by holding off. Why? Because even the best trackin scopes aren’t perfect, especially on the first shot. It often takes a shot or two to “settle” after making an adjustment. The idea of dialing a scope and then shooting at an animal without getting a confirmation shot or two on paper erks me to the core, as does a knob without a screw down cap. Maybe it shouldn’t CAUSE a miss at 300-400 yards, but then you really don’t have to be dialing at that range anyway. While it may not CAUSE a miss, it could certainly contribute to one. I know I’ve seen quite a few videos of people ranging an animal, dialing a scope, and then missing a shot they were confident in. I can’t help but wonder if the miss was not entirely their fault.
I love the Leupold scopes that I’ve owned, and will own more in the future. That said, when I was shooting matches they were somewhat known for RTZ and tracking issues. Weaver/Sightron, Nightforce, S&B, and March were the ones people trusted the most. Even so, most guys wouldn’t touch a knob once it counted. For hunting guns I’ve always sighted in and then never touched a thing again until I changed loads.
I love the Leupold scopes that I’ve owned, and will own more in the future. That said, when I was shooting matches they were somewhat known for RTZ and tracking issues. Weaver/Sightron, Nightforce, S&B, and March were the ones people trusted the most. Even so, most guys wouldn’t touch a knob once it counted. For hunting guns I’ve always sighted in and then never touched a thing again until I changed loads.
That means in Colorado what??
D
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Accomplished match shooter who lobs wild guesses at bulls, great stuff.
A zero set too far can make for an unacceptable mid-range height. I'm more used to and comfortable with holding over. Won't zero a rifle where the height before the zero is too high.
ImBillT
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Matches are fired at known ranges with wind flags and sighter shots. Hunting does not have much crossover beyond loading ammo, gunhandling, and trigger control. I thought the elk was much closer. After the first shot I had more information to go on. Same with the second. That hunt and situation were not my preferred method of doing things. I’ve admitted as much. This doesn’t change my experience regarding dialing scopes around.
ImBillT
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Totally agree and this is very important.I try to keep my max height at less than 2.5” above line of sight. That may be too conservative, but most cartridges can be zeroed out to 200yds without exceeding that number.
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Colorado..........perhaps he references the wacky tobaccy?
Oh, I got it, just discounted it. I guess I need to type higher...Right over your head
Washington Hunter
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I've always used Leupolds and the standard duplex reticle, but in the last few years I've been switching all my rifles over to the Long Range Duplex reticle. Even if I don't use the holdover dots, I don't know that they hurt anything. I was able to make use of it this year in Wyoming with my 338 Win. Mag. and my Leupold VX-1 3-9x40. Had an antelope at 350 yards. My rifle was zeroed at 200 yards, and the holdover points are approximately on at 300, 400, and 500. So I just had to bracket the antelope between the 2nd and 3rd dots, and the 200 grain Nosler Ballistic Tip hit it perfectly. Yes I could have got by just fine with a regular duplex reticle but I'm more confident having the holdover points. I hope to practice more with it before next hunting season and try to become proficient at 500 yards.
Almost forgot- I use an app on my phone called Strelok. Put in the data, muzzle velocity, bullet b.c., zero distance, etc. and it will give you the zero distance for each holdover point. It's very handy as I can play around with the numbers until I get the holdover points to be good for 300, 400, and 500 yards. I just like them to be good for even 100 yard increments so it's easy to remember.
Almost forgot- I use an app on my phone called Strelok. Put in the data, muzzle velocity, bullet b.c., zero distance, etc. and it will give you the zero distance for each holdover point. It's very handy as I can play around with the numbers until I get the holdover points to be good for 300, 400, and 500 yards. I just like them to be good for even 100 yard increments so it's easy to remember.
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While at the range just for chits and giggles aim with the lower thick to thin point of the duplex on the target with the scope set on 10power to see how high it shoots at 100. That is after you have zeroed at whatever distance you prefer. You have one built in hold over just figure out at what range it is. You won’t be disappointed but remember that the power ring will change POI. Just an FYI, do with it as you like.
ImBillT
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Many manufacturers list this measurement in the specs. Field confirmation is always a plus.
