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Thread: Figuring your bullet drop for a dope card???

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    Figuring your bullet drop for a dope card???

    I went to buy a scope dope today and the guy told me to shoot 3 rounds at each distance on the card. then take the average of each shot at each range and use that for my dope.

    Am I being fed bullshit here?

    Can someone explain how they figure a scope dope car?
    Originally Posted By: Rosie Palma

    If you're truly worried about a bear attacking you after shooting your whitetail deer, then I suggest 12 gauge with slugs. When you're field dressing, place some claymores on the perimeter and have your hunting buddy conduct overwatch with the 50 BMG...

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    Re: Figuring your bullet drop for a dope card???

    ballisic program
    heres what you need though, BC, MV, atmospheric conditions you will be shoting in, range you will be shooting (for .308 just go 0-1000y)

    So to the point, unless you know your MV with a particular ammo, you wont be able to get good results. What most do w/o a chrony is to take your best guess, get your dope, then go shoot to test your dope. If it doesnt match, go back to the program and play with the MV intil your data matches better, and go w/ that.
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    Re: Figuring your bullet drop for a dope card???

    That be a good way to get it. I used a large peice of carboard. I painted a 3 inch line about five inches down from the top, and line the cross hairs up on that. Shoot three and measure from line down to impact and that would be your hold over for your chart.

    Joker59 =^)

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    Re: Figuring your bullet drop for a dope card???

    Originally Posted By: wjwill
    I went to buy a scope dope today and the guy told me to shoot 3 rounds at each distance on the card. then take the average of each shot at each range and use that for my dope.

    Am I being fed bullshit here?

    Can someone explain how they figure a scope dope car?


    The first question you have to ask is how far are you going to be shooting? What's really the furthest distance you're going to shoot? If you're shooting out to 300 to 500 yards his method will work fine. Shoot groups at each distance record the difference from POA to POI and make your ballistic card.

    If you're going to be realistically shooting beyond 500 yards then a ballistic program and chronograph come in very handy to get in the ball park.
    Jeff

    Distance is not an issue, but the wind can make it interesting!

    John 3: 1-21

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    Re: Figuring your bullet drop for a dope card???

    I plan on trying to shoot it out to 800 yards tops. I all this math and figuring got me feeling like a retard.

    the barrel is 20 inches long with a 1:10 twist rate. The ammo I will be using is 147 grain Q3130 winchester.
    Originally Posted By: Rosie Palma

    If you're truly worried about a bear attacking you after shooting your whitetail deer, then I suggest 12 gauge with slugs. When you're field dressing, place some claymores on the perimeter and have your hunting buddy conduct overwatch with the 50 BMG...

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    Re: Figuring your bullet drop for a dope card???

    My personal belief is that getting an average of 3 rounds fired its near useless. Shoot at least 5-10 rounds before getting averages. I watch guys try to zero scopes at the shooting range all the time, firing one round, clicking away, firing again, clicking away, and they go through a whole box and never get sighted in. Shoot a 5-10 shot group, then get your average point of impact and then adjust your scope. (I know this isn't really on topic, but it is relevant info)

    If you want an accurate dope chart, your best bet is to shoot 10 shot groups at all your different ranges and record the deviations firsthand as opposed to trying to plug in values into a calculator. This one seems pretty useful, http://www.eskimo.com/~jbm/cgi-bin/jbmtraj-5.0.cgi but I wouldn't assume the results to be spot on at all those ranges, more like general guidelines of where the bullet should be.

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    Re: Figuring your bullet drop for a dope card???

    Originally Posted By: wjwill
    The ammo I will be using is 147 grain Q3130 winchester.


    Exbal list Winchester USA 147gr FMJ with a MV of 2800fps.
    based on 1.5" sight above bore, a BC of .414, Altitude at 1100ft, Temp 70deg, RH 50%, pressure set to 29.92.

    Target Dist = 800yds Wind value 5mph from 9

    Velocity = 1357fps, flight time = 1.2426 sec, Energy 601ft/lb, Elevation = -208.3", Windage = 33.9"

    Elev Correction = 24.75MOA, Wind = -4.00moa (@ 800 yds)

    775yds = 23.5moa -4moa wind
    750yds = 22.0moa -3.75wind
    725yds = 20.75moa -3.5
    700yds = 19.5moa -3.5
    675yds = 18.25moa -3.25
    650yds = 17.25moa -3.0
    625yds = 16.0moa -3.0
    600yds = 15moa -2.75
    575yds = 13.75moa -2.5
    550yds = 12.75moa -2.5
    525yds = 11.75moa -2.25
    500yds = 10.75moa -2.25
    475yds = 10.0moa -2.0
    450yds = 9.0moa -2.0
    425yds = 8.25moa -1.75
    400yds = 7.25moa -1.75
    375yds = 6.5moa -1.5
    350yds = 5.75moa -1.5
    325yds = 5.0moa -1.25
    300yds = 4.25moa -1.25

    Hope this helps

    Terry

    Output from JBM

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    Re: Figuring your bullet drop for a dope card???

    While you are all on the subject of figuring out dope....Is there a way to figure out dope for various ranges with out a ballistic program?

    I'm zeroed at 100yrds, shooting 168gr FGMM ammo. I have a lot of different formulas and have got myself a bit confused with some of the math. I'd appreciate some help from any and all hide members that would like to offer.
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    Re: Figuring your bullet drop for a dope card???

    your barrel length makes a huge difference in velocity too. I just got done working up a hand load and according to the book I should have been just shy of 2600 fps, how ever after figuring my drop and pluging it into a bal program I found I was down around 2450 fps.... So just because a load in a book says one thing dosnt make it true.

    the difference was the test gun for the book had a 24" and mine is 20.

    To get my drop I simply zeroed at 100 shot a group at 300 and measured down, then plugged it all in. A crono is the way to go for sure but I dont have one, so I had to do what I could with what I had.

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    Re: Figuring your bullet drop for a dope card???

    It all changes...and a program will get you very close but nothing will be able to get you exactly gnats ass out to 800 yards 1st shot every time. Unless you figure the program and then actually figure the real world drop associated with what your chart says....maybe 8% more drop in the real world...if you can get the error % figured for whatever program you run it would help....there are some out there that if you feed it the info it will get you on paper 1st shot though.

    Best cheapest way to do it is to get an idea from a program then find out how much more is needed for POA =POI with your ranges and just right the MOA/MIL needed to get there.....forget the drops because it ends up getting confusing for beginners to translate 246" of drop at 800 yards into 1/4 MOA adjustments. Just note your asjustments on your scope...hell I was able to get my 223 Rem out to 820 yards with a Lupy 2.5x with 1MOA adjustments....just fire a few and then adjust up untill you are close to the target and just hold for wind.....if you write down your adjustments for the lower ranges just spin back....mine was at the "9" for 100 yards...."24" for 575 yards and "43" for 820 yards.
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    Re: Figuring your bullet drop for a dope card???

    The simplest way to get dope without any ballistic computer or cartridge data is to proceed as follows.

    Zero at 100 yards.
    Move to 200 and shoot a group, at least 5 shots.
    Measure the drop with a ruler to center of the group, convert to the click value of your scope. Dial that on, shoot another 5 to confirm.
    Move to 300, and repeat the exercise.

    At 400, the drop is enough that shooting with a 300 yards zero will often put you below the average size target backer. At 400, add the same amount you came up between 200 and 300 to your 300 yard zero. For 500, add the same amount you came up from 300 to 400, do the same for 600. At 700, come up the value between 500 and 600 plus half the value, same for 800, at 900 and 1000 add 3/4

    For example, you zero at 100 yards. At 200 yards, the 100 yard setting leaves you 4" low. Dial up 2 MOA, shoot to confirm, you should be right on. At 300, your group turns out to be 9" low with the 200 yard setting. Add 3 MOA and shoot to confirm.

    Now you have 5 MOA up to shoot at 300. To start at 400, come up the same 3 MOA you came up to get to 300 from 200. With 8 MOA dialed on, shoot a group and correct up or down as required, you'll be within 1 to .5 MOA or so. Let's say that left you 1/4 MOA high, so 7.75 is correct. Come up 2.75 more and shoot at 500. That puts you at 10.5, you find that to be 1/2 MOA low, so 11 is correct. Add 3.25 and shoot at 600. 14.25 turns out to be .75 low, so 15 MOA is correct for 600. At 700, add the 4 MOA differance between 500 and 600, plus half that, 6 MOA total, 21 MOA on the gun.

    This process will put you pretty close, withing a minute or so at each range.

    I run zeros with my classes this way all the time, it works quite well.
    Cory Trapp
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    Re: Figuring your bullet drop for a dope card???

    What ballistic program can create these dope cards?
    Thanks Bill


    Originally Posted By: suasponte
    Originally Posted By: wjwill
    The ammo I will be using is 147 grain Q3130 winchester.


    Exbal list Winchester USA 147gr FMJ with a MV of 2800fps.
    based on 1.5" sight above bore, a BC of .414, Altitude at 1100ft, Temp 70deg, RH 50%, pressure set to 29.92.

    Target Dist = 800yds Wind value 5mph from 9

    Velocity = 1357fps, flight time = 1.2426 sec, Energy 601ft/lb, Elevation = -208.3", Windage = 33.9"

    Elev Correction = 24.75MOA, Wind = -4.00moa (@ 800 yds)

    775yds = 23.5moa -4moa wind
    750yds = 22.0moa -3.75wind
    725yds = 20.75moa -3.5
    700yds = 19.5moa -3.5
    675yds = 18.25moa -3.25
    650yds = 17.25moa -3.0
    625yds = 16.0moa -3.0
    600yds = 15moa -2.75
    575yds = 13.75moa -2.5
    550yds = 12.75moa -2.5
    525yds = 11.75moa -2.25
    500yds = 10.75moa -2.25
    475yds = 10.0moa -2.0
    450yds = 9.0moa -2.0
    425yds = 8.25moa -1.75
    400yds = 7.25moa -1.75
    375yds = 6.5moa -1.5
    350yds = 5.75moa -1.5
    325yds = 5.0moa -1.25
    300yds = 4.25moa -1.25

    Hope this helps

    Terry

    Output from JBM


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    Re: Figuring your bullet drop for a dope card???

    Most all the programs will provide a printout of the drop data, some can be configured to print just what you like. Absent that, you can just print to a file, then eidt it to display just what you like in the format you want. Using Excel, I put the data into nice divided and shaded cells for easy reading, size the font to put the firts 400 yards inside the scope lens cap and the rest on the side of the rifle.
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    Re: Figuring your bullet drop for a dope card???

    "The price of reclusion in the beauty of nature is poverty and namelessness. Or, perhaps, the price is itself the reward."
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    Re: Figuring your bullet drop for a dope card???

    Lindy
    Thanks I owe you one .
    Just what I was looking for
    Bill

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    Re: Figuring your bullet drop for a dope card???

    Here is a picture of a bullet drop chart I made for a load I had! Aim point at top of sheet, move to each range you want and fire 5 shots for group. This confirms my calculated to real world! You can also confirm your wind adjust too!

    Always aim at the top aim point and let the bullts fall where they may.



    don't remember what this was for since I have done several!

    Searched my records. This is for 308 147gr CBC's at 2700fps. The 147gr bullets drop like a bitch past 300m. Not a match grade load by any means! But still gets me some trigger time!

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    Re: Figuring your bullet drop for a dope card???

    This relates to the problem I have. I now have a couple loads worked up for my newly aquired AR30, and want to start doing some long range shooting. I am using Nightforce ballistics calculator which is nice, but I understand that their numbers probably won't be exact with the real world. This summer I will have plenty of time to zero at 200yds and figure all my dope out to 1000yds; However when deer season comes around and I want to try some 600-800yds yard shots, the 50 to 100 degree tempurature change from my summer dope will definately change(not to mention the muzzle vel itself [img]<>/eek.gif[/img]). So i want a way that I can go out, zero my gun at 200, then go out to 500 and figure out all my dope. Any programs like that? or is the best way to tweak the NF ballistic calculator to get the right moa adjustment at 500yds and go from there.
    Oh, and anyway know where I could get small hand held dope cards that are durable and could be carried in a pocket, or should I just take the time and make some on excel?

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    Re: Figuring your bullet drop for a dope card???

    IMO the Night Force, and Exbal Ballistic calculators will get you close enough to put a kill shot on a deer, even a groundhog! If you have a Kestrel anemometer that gives you the temp, RH, and altitude where you are and know your muzzle velocity you will bring home the meat!

    I know that I am within 1.75moa out to 800m with the exbal. That is a hit on a deer and a groundhog!

    As for the dope cards use JBM and laminate the output cards! Leave excess at the top and drill a hole thru it. Get some brass chain from Home Depot and use it to attach to the scope base!

    JBM Ballistic Calculations and Trajectory Cards



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