Quick Drop vs Danger Space

[24valve]

Ok, had some time to wrap my head around this a bit and I have some additional questions for the brain trust. Maybe Im misunderstanding or misusing some of this, but it seems many of the advantages of QD are really degraded if you dont have a cartridge that fits into it exceptionally well, but notably also anytime a “partial” or non-linear correction is required on top of the basic qd math. Hence the original question obviously, but given the necessary adjustments it seems even many guns that “fit into QD” will run into this at some DA where a correction is needed…

First, NONE of my guns fit into QD as well as those pictured. That may be the first issue. If I go way up in DA to something like a “western mountains” zone my 6.5’s start to fit pretty well. But just as an example, this morning waking up Im at NEGATIVE 3000’ DA. So nothing I have is a perfect “base qd” that stays within a tenth out to full practice range. So I’ve got limited range to functionally use base QD (which is +\- where Ive had success using it), and/or I frequently have MULTIPLE correction factors just at one DA. Example is my 270, where I can use base qd to 350yds, but after that I have to use a .5 correction. So if “mental load” is a significant goal, then it’s basic qd math (easy enough) but only to 350 yards (hardly past pbr), then past that range its a different math with a correction. The key is that frequently I’ve not been able to apply one correction across the entire trajectory, which introduces an additional thing to remember and an additional mid-shot decision. So “in the moment” when QD is useful, Im left with
1) qd math
2) multiple corrections to remember
3) in the moment decision: choose WHICH correction factor to use
4) apply correct correction factor

Thus far when practicing on a clock I have been unable to consistently apply the correct adjustment to the base qd when Im hovering around my cutoff range (ie first shot is at base qd, but a follow up enters the range where a correction is needed, or vice versa).

So Im left asking the same question that I have been struggling to articulate. I do understand base qd. I do understand a standard correction to it. The issue is that in my situation, for the guns I have, it’s rarely been that simple, even with standard cartridges. In order to stay within a reasonable amount of error for a first shot at an animal, what applies is multiple correction factors all at the same DA. To me this is not achieving “lower mental load”. And while I may have taken one too many wacks to the head as a child, my apparently-smooth brain just hasnt managed it well.

So, in this case, is there a simpler solution? Why not a taped BDC turret marked in yardage…in conjuntion with a correction factor? Folks have argued pretty vocally that such a turret is a bad idea, and I would have tended to agree…but Im curious on this, given the specific situation what youd actually be giving up, and what situations that would make a difference? I guess it just seems to me that utilizing yardage on the turret with ZERO math, and then only using and having to remember a correction factor (ie “dial to X marked on turret, then dial correction clicks) is actually less of a mental load than QD+correction, but would utilize the same correction factor in order to achieve equal precision across DA’s without needing the math. Plus, if that allows a flatter-shooting cartridge it would have the benefit of 1) minimizing the correction needed in the first place, and widening the range of DA’s where no correction is needed, 2) minimizing the impact of ranging errors, etc, everything that goes with that flatter trajectory.

Curious on folks thoughts on this.

You are correct in that what makes QD so useful is it's simplicity and low mental load, and that is diminished when there's multiple correction factors to remember.

Before getting to alternatives, I am curious as to why none of your rifles match up. 6.5 creedmoors are usually close, and fast, flat rifles like your 270 usually match QD better with lower DA. Would you mind sharing some more info on the rifles, bullets, velocities, and dope charts you're working with?

For example, below is a 243 with 95 TMK's at -3,000 DA. It's base QD out to 600.



And the 223 from my previous example: base +0.3 out to 500.

 

[SkeeterMcgiblet]

I dove in to Quick Drop when I bought a "dial-y" scope last year. From the Form provided info I made my own cheat sheet & examples as I worked through learning it. Spreadsheets are what I do for work so putting everything into tables really helps show the trends and better understand the the system and how to adjust for different MVs / Loads (168 vs 175 SMK for 308). Admittedly I only own a 308 that fits pretty well with QD so I'm a believer and dont have any experiences with other cartridges that may not work well with QD. Hopefully this helps some people better grasp the system.

 

[Macintosh]

I guess the point and the resulting questions are twofold.
1). I am challenging the statement that “a simple 0.5 correction applied beyond 350yds” is an easy thing.
2) i am saying that some rifles that ARE friendly, BECOME unfriendly as you go to an extreme of DA.

Example: My 20” 6.5cm is shooting a 140 eldm at 2598fps mv. Thats garmin chrono velocity. Im at a DA today of -3000’. According to my AB, which is pretty well trued, regular QD puts my cone center almost 5” off target beginning at 300yds, and increasing from there. At 700 yards cone center is off .6mils, or over 16” from poa. Depending on the max range I want to use QD, I can use a correction factor anywhere from .1 thru .4 to do better.
BUT, the exact same rifle at a DA of 8000’ the basic QD formula has me within .1mil all the way past 800 yards.
Two different DA’s, two completely different QD situations.

I have the opposite case with my 270 shooting regular ttsx’s (270win, 130ttsx @3000fps). It fits QD pretty well here near sea level, but it breaks down and requires a correction factor past 350 when Im at a high DA.

So thats what Im getting at:
1) I do not accept on its face that a correction factor applied only at certain distances is a simple thing that sufficiently achieves “reduced mental load” such that it can be brushed off as easy under stress. I may very well be a smooth-brained exception, but I suspect Im not the only one.
2) many guns only fit perfectly into QD across some range of DA. What do you do if you spend time outside that range?

 

[Nine Banger]

Could you elaborate? If youre suggesting I just need a gun that matches better, neither my 24” nor my 20” 6.5creedmoors match especially well with factory-loaded 140eldms, they are better than the example gun I used but only out to moderate range and definitely not as cut and dried as the examples others have posted about, so I think its fair to say its not only an issue of uber-flat shooting cartridges.

It's an opportunity to get a 6.5PRC with a shorter barrel if you want that diameter cartridge or get a 6 or 22 with a shorter barrel.

 

[JF_Idaho]

I know a lot of people are against it. But for those of you running 223 (77tmk especially) with a correction factor, take a look at a 50 yard zero. You're welcome.

 

[longrangelead]

I guess the point and the resulting questions are twofold.
1). I am challenging the statement that “a simple 0.5 correction applied beyond 350yds” is an easy thing.
2) i am saying that some rifles that ARE friendly, BECOME unfriendly as you go to an extreme of DA.

Example: My 20” 6.5cm is shooting a 140 eldm at 2598fps mv. Thats garmin chrono velocity. Im at a DA today of -3000’. According to my AB, which is pretty well trued, regular QD puts my cone center almost 5” off target beginning at 300yds, and increasing from there. At 700 yards cone center is off .6mils, or over 16” from poa. Depending on the max range I want to use QD, I can use a correction factor anywhere from .1 thru .4 to do better.
BUT, the exact same rifle at a DA of 8000’ the basic QD formula has me within .1mil all the way past 800 yards.
Two different DA’s, two completely different QD situations.

I have the opposite case with my 270 shooting regular ttsx’s (270win, 130ttsx @3000fps). It fits QD pretty well here near sea level, but it breaks down and requires a correction factor past 350 when Im at a high DA.

So thats what Im getting at:
1) I do not accept on its face that a correction factor applied only at certain distances is a simple thing that sufficiently achieves “reduced mental load” such that it can be brushed off as easy under stress. I may very well be a smooth-brained exception, but I suspect Im not the only one.
2) many guns only fit perfectly into QD across some range of DA. What do you do if you spend time outside that range?

like anything, QD has its limitations and ideal operating range.
outside that ideal range, you are correct, it's no easier because you have to do all the things that QD eliminates.

it's really that simple, it works or it doesn't.

I realize not everyone has a safe full of guns to choose from, but if you do have multiple different rifles/cartridges, when one doesn't work, a different one may work.
Or if you hunt sea level and 11,000 regularly, it might make sense to have a rifle set up for the average DA for each place.

people keep pointing out the instances where it doesn't work and want to call it pointless or whatever.

In the cases where it does work, which is all I care about, it's stupid quick and easy.

So stupid quick and easy, I'm one of the ones setting up several rifles specifically for QD/avg gun.

For me, most of my fall hunting and all of spring bear fall within average DA's that allow me to use QD.
At that point it's just a matter of range, what rifle/bullet/velocity do I need for the potential max range.

 

[Macintosh]

That makes sense. Also, just to note, Im not saying any of this as a rationale against qd. I’m saying it because Ive used it and like it, and Im trying to find a better way to do it without a complete re-do of my safe, which just aint happenin.

Unfortunately, living and practicing in a cold/low elevation climate is not conducive to practicing with the gun you take to 9000’ in october elsewhere.