Stuck on Quick Drop

[HuntHarder]

Like long range lead said there is almost always a good gun/ bad gun factor.. if you post or send your ballistic profile we can help you with that. My .223 is a “bad” gun and has a correction factor of +.3..

So essentially range -2, +/- .3 (either 1.7 or 2.3) depending which side of bad your gun is on, for your .223? This holds true and is linear out to say 700 yards?

 

[huckfin]

With faster cartridges I have found running a 200 yard zero and memorizing the holds for 300,400,500 is easier. Then use your QD for ranges 600-800 where the bullet has slowed down enough that its trajectory lines up for a QD solution.

 

[Wprinkle]

So essentially range -2, +/- .3 (either 1.7 or 2.3) depending which side of bad your gun is on, for your .223? This holds true and is linear out to say 700 yards?

It’s essentially-2 for an average gun.. the +.3 was an example as i have a 16” barrel on my 223 and with practice ammo fairly poor speeds. This is much easier to explain on words (for me) if you would like help pm me and I’ll send you my number.. once you see it you “got it”.: back to Ryan’s question for my fast 6mm is was close enough to use quick drop but i backed off speed just a little and it works perfectly out past 700. Next barrel will be shorter to accomplish this without having to back off powder charges..

 

[Jimbee]

I've shot a few NRL Hunter matches and having a combo that works for quick drop is so much faster than having to look at a dope card. I can definitely see the value in slowing a cartridge down to accommodate easy mental math. My 6mms don't line up very well but would probably be close enough if I used "average gun" to around 400yds and "good gun" for further distance if I was in a hurry.

 

[SkeeterMcgiblet]

I've shot a few NRL Hunter matches and having a combo that works for quick drop is so much faster than having to look at a dope card. I can definitely see the value in slowing a cartridge down to accommodate easy mental math. My 6mms don't line up very well but would probably be close enough if I used "average gun" to around 400yds and "good gun" for further distance if I was in a hurry.

Form's QD & Wind is the main reasons I feel I had success at NRL as a noob who had never shot past 300 yds last season and even felt comfortable enough signing up for a competition. My 22" 308 with 168s @ ~2675 hits almost exact to "minus 2.0" out to 700 (Colorado, DA around 7-10k average). Prepping for my first match I made the cheat sheet below and would practice getting shot solutions with random numbers from a dungeons and dragons die set. It may not be perfect but I think it was a great starting point and hopefully it can help someone else.

I feel understanding the actual margin for error with QD as being very important, personally I made a chart that showed me when QD would put me past an error of 3" at each range.

I'm a construction nerd who's life is "high stakes basic math" and use excel for everything and felt seeing the data in a table helped me understand the system the best.

Its such an easy & reliable system that I've pondered getting a 6.5 prc or 6 creed and chopping barrel to maintain the "minus 2" QD and have a great short mountain rifle that works for the realistic ranges I'd shoot.

 

[longrangelead]

So essentially range -2, +/- .3 (either 1.7 or 2.3) depending which side of bad your gun is on, for your .223? This holds true and is linear out to say 700 yards?

basically yes, there is more to it for good/bad but it's hard to articulate the simplicity typing it out.

 

[SkeeterMcgiblet]

Form's QD & Wind is the main reasons I feel I had success at NRL as a noob who had never shot past 300 yds last season and even felt comfortable enough signing up for a competition. My 22" 308 with 168s @ ~2675 hits almost exact to "minus 2.0" out to 700 (Colorado, DA around 7-10k average). Prepping for my first match I made the cheat sheet below and would practice getting shot solutions with random numbers from a dungeons and dragons die set. It may not be perfect but I think it was a great starting point and hopefully it can help someone else.

I feel understanding the actual margin for error with QD as being very important, personally I made a chart that showed me when QD would put me past an error of 3" at each range.

I'm a construction nerd who's life is "high stakes basic math" and use excel for everything and felt seeing the data in a table helped me understand the system the best.

Its such an easy & reliable system that I've pondered getting a 6.5 prc or 6 creed and chopping barrel to maintain the "minus 2" QD and have a great short mountain rifle that works for the realistic ranges I'd shoot.

Also to further nerd out I had a "modified" QD for 175s at ~2600 fps that came out to "minus 2, plus 0.2" from "average gun" for a QD factor of 1.8. The greyed out areas are ones that I figured were a constant (200, 300 yds) and need to be calced or hard doped (past 600 yds). Red highlihts are for anything over 0.3 mil error from actual dope which I deemed "un-acceptable" for precision.

 

[BBob]

With faster cartridges I have found running a 200 yard zero and memorizing the holds for 300,400,500 is easier. Then use your QD for ranges 600-800 where the bullet has slowed down enough that its trajectory lines up for a QD solution.

I have a ballistic twin to a 6UM IMP and this (200yd zero) works pretty darn well. It uses a base -3 correction plus a yardage correction factor. Not sure I can type it out to make sense but I could try.

Edit: I’ll add that it adds a little extra mental gymnastics and isn’t as fast as with a rifle that fits the perfect QD mold. It’s doable but you have to remember the corrections just for this rifle. In the end probably not faster than a range card but you wouldn’t have to come off the rifle to do it with the modified QD.

 

[lefthandedasian]

Next barrel will be shorter to accomplish this without having to back off powder charges..

Excuse my ignorance, I don't reload at all (or yet) but why would you do this exactly? Seems like both ways accomplish the same velocity out of the barrel which results in the same QD and effective range right? A longer barrel with less powder charge seems like it would give (marginally) less recoil, less muzzle blast and be cheaper on your wallet by saving powder. Would running a full charge reduce SD's or something like that to make the full charge more advantageous? Like I said I don't know anything about reloading but seems silly to me to cut the barrel down and use more power and increase reload costs, more recoil and more muzzle blast just to achieve the same velocity as the previous setup.

 

[Nine Banger]

Excuse my ignorance, I don't reload at all (or yet) but why would you do this exactly? Seems like both ways accomplish the same velocity out of the barrel which results in the same QD and effective range right? A longer barrel with less powder charge seems like it would give (marginally) less recoil, less muzzle blast and be cheaper on your wallet by saving powder. Would running a full charge reduce SD's or something like that to make the full charge more advantageous? Like I said I don't know anything about reloading but seems silly to me to cut the barrel down and use more power and increase reload costs, more recoil and more muzzle blast just to achieve the same velocity as the previous setup.

Take a look at @longrangelead's gun up a few posts. (Speaking of which, Lowe's called, they want their 2x4 back.)

It's fun to carry around a short gun with an OTB suppressor.

It's easy to get Quick Drop with 22 creed and 6 creed and short barrels.

 

[longrangelead]

Take a look at @longrangelead's gun up a few posts. (Speaking of which, Lowe's called, they want their 2x4 back.)

It's fun to carry around a short gun with an OTB suppressor.

It's easy to get Quick Drop with 22 creed and 6 creed and short barrels.


View attachment 979292View attachment 979293

that Maple 2x4 is just "rustic"

 

[longrangelead]

Excuse my ignorance, I don't reload at all (or yet) but why would you do this exactly? Seems like both ways accomplish the same velocity out of the barrel which results in the same QD and effective range right? A longer barrel with less powder charge seems like it would give (marginally) less recoil, less muzzle blast and be cheaper on your wallet by saving powder. Would running a full charge reduce SD's or something like that to make the full charge more advantageous? Like I said I don't know anything about reloading but seems silly to me to cut the barrel down and use more power and increase reload costs, more recoil and more muzzle blast just to achieve the same velocity as the previous setup.

I worked down in barrel length to get to QD velocity so I'm not really doing anything different than if I had a long barrel.
I wanted QD #1 and a short barrel #2
I shot it at factory length for velocity. (22"?)
again at 16"
again at 15"
again at 14.5"

I considered 14" but then I'd have to do as you describe and start working for it.

Admittedly, this is with a near max load in brass with the shallow shoulder angle of the 243 case.
The same load in Fury cases is 50ish fps faster without the pressure/shoulder issue(slight bolt lift only). I'm loading less in the Fury case to do the same thing as brass currently.
If I AI the chamber I'm positive brass would be just fine again due to less case growth.

It might seem like a lot of work or the long way around but it's the same thing as doing a 7-300 Norma improved to shoot x bullet @ 3600fps right?

it meets the intended goal.

 

[Marbles]

A 6 UM throwing a 115 DTAC at 3300 fps simply doesn't work with any correction factor at closer ranges. So,

Also to further nerd out I had a "modified" QD for 175s at ~2600 fps that came out to "minus 2, plus 0.2" from "average gun" for a QD factor of 1.8. The greyed out areas are ones that I figured were a constant (200, 300 yds) and need to be calced or hard doped (past 600 yds). Red highlihts are for anything over 0.3 mil error from actual dope which I deemed "un-acceptable" for precision.

View attachment 979228

While generally there is no reason to convert MRAD to inches, this is one of the exceptions as error on target is what matters. 0.2 mil error at 650 yards is 4.7 inches, but at 350 yards a 0.3 mil error is only 3.2 inches and "unacceptable".

At 750 yards the "acceptable" 0.2 mil error is 5.4 inches. So for the 175 SMK everything but the 550 yard error (5.9 inches) should be accepted too.

 

[longrangelead]

A 6 UM throwing a 115 DTAC at 3300 fps simply doesn't work with any correction factor at closer ranges. So,

While generally there is no reason to convert MRAD to inches, this is one of the exceptions as error on target is what matters. 0.2 mil error at 650 yards is 4.7 inches, but at 350 yards a 0.3 mil error is only 3.2 inches and "unacceptable".

At 750 yards the "acceptable" 0.2 mil error is 5.4 inches. So for the 175 SMK everything but the 550 yard error (5.9 inches) should be accepted too.

going off topic a little, but this is where the dispersion of the rifle and the ability of the shooter come in.
IF, the shooter is a 2 MOA shooter, double that error as potential total error as long as the dispersion of the rifle is within that 2 MOA.

A 2MOA shooter quickly reaches max effective range on a 10" target.

 

[HuntHarder]

How do you measure a shooter's MOA?

 

[longrangelead]

How do you measure a shooter's MOA?

Form has by far the most experience here. According to him, this timed drill is something like 90-95% accurate of what a person will shoot like in the field under stress/excitement.

I shot this my first time through S2H. After getting a real zero on the rifle, this timed drill exposed my tendency to put to much cheek pressure on the right side of the butt driving the muzzle left.

 

[Wprinkle]

Excuse my ignorance, I don't reload at all (or yet) but why would you do this exactly? Seems like both ways accomplish the same velocity out of the barrel which results in the same QD and effective range right? A longer barrel with less powder charge seems like it would give (marginally) less recoil, less muzzle blast and be cheaper on your wallet by saving powder. Would running a full charge reduce SD's or something like that to make the full charge more advantageous? Like I said I don't know anything about reloading but seems silly to me to cut the barrel down and use more power and increase reload costs, more recoil and more muzzle blast just to achieve the same velocity as the previous setup.

So I’ll try to keep it not a novel lol and I’m just a dude that like to shoot and hunt I’m no expert anything. But I’m going short barrel because i want to try it. You’re absolutely correct a lighter load would save powder and accomplish the same thing. It actually even produces (on average) lower SD and ES with tighter groups when i use a light load. The answer probably is same barrel length with a lighter load to get QD aligned. But i like to experiment and i wanna try the short barrel.

 

[Marbles]

going off topic a little, but this is where the dispersion of the rifle and the ability of the shooter come in.
IF, the shooter is a 2 MOA shooter, double that error as potential total error as long as the dispersion of the rifle is within that 2 MOA.

A 2MOA shooter quickly reaches max effective range on a 10" target.

But, that doesn't address the issue. We are talking about consistent error that increases the depression of the system by stacking on top of everything else, and people in this thread are talking about 700 yards shots in examples.

For hitting a target of a certain size, adding 0.3 mil (why switch between mil and MOA in the discussion) of error at 200 yards is meaningfully different than adding 0.2 mil of error at 700 yards whether or not it is a 0.5 mil or 0.3 mil system. One is worth mental effort to avoid, the other still leaves an acceptable miss rate.

Put differently, one is pol vaulting over mouse turds, the other needs to be accounted for.

 

[Schmo]

one is pol vaulting over mouse turds

Whelp, that’s about the highest thing I can pole vault anyway

 

[longrangelead]

But, that doesn't address the issue. We are talking about consistent error that increases the depression of the system by stacking on top of everything else, and people in this thread are talking about 700 yards shots in examples.

For hitting a target of a certain size, adding 0.3 mil (why switch between mil and MOA in the discussion) of error at 200 yards is meaningfully different than adding 0.2 mil of error at 700 yards whether or not it is a 0.5 mil or 0.3 mil system. One is worth mental effort to avoid, the other still leaves an acceptable miss rate.

Put differently, one is pol vaulting over mouse turds, the other needs to be accounted for.

the target is in MOA I assume because it's close to 1 inch increments which makes sense to people and is easy to measure.

unless I missed your point, my point was human error will possibly double (or more) a math error.

if the math error equates to 5.5" inches at 550yds, (1 Moa for the parallel) a 2 MOA shooter is at 11" with no other error like wind introduced.