Which BDC reticle most closely matches the 65G?

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  • RANGER
    Warrior
    • Oct 2016
    • 102

    Which BDC reticle most closely matches the 65G?

    I have a Leupold Mk6 1-6 CMR (7.62) scope that I was thinking of using on my 16".

    Two questions....

    1) Will the subtensions that are set for the 7.62 (which I'm assuming is M118) be close to the 6.5G ? Or would the 5.56 be a closer match?

    2) if the basis of this rifle is to ring steel at 300-800 yards would I be better off with 18"? What range does the extra 2" matter?
  • VASCAR2
    Chieftain
    • Mar 2011
    • 6219

    #2
    I think the Leupold scope is for the 175 grain SMK in 7.62. Comparing to a 16” 6.5 Grendel this is what I got using Hornady ballistic computer.


    The CMR-W reticle is based on a 175gr Sierra MatchKing with a muzzle velocity of 2575fps and a 50 meter zero.

    I calculated 7.62 with 175 grain SMK .496 BC at 2585 FPS, 2.75” over bore I used 100 yard zero.


    308 175 .264 .505 @ 2800 fps and above
    .496 between 2800 and 1800 fps
    .485 @ 1800 fps and below




    Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
    0 2585 2596.0 -2.8 0.0 0.0 0 0 0
    50 2497 2422.0 -0.7 1.3 0.4 0 0 0
    100 2410 2257.0 0.0 0.0 0.0 0 0 0
    150 2326 2102.0 -0.8 0.5 0.2 0 0 0
    200 2243 1954.0 -3.2 1.5 0.5 0 0 0
    250 2161 1815.0 -7.4 2.8 0.8 0 0 0
    300 2082 1684.0 -13.4 4.3 1.2 0 0 0
    350 2004 1560.0 -21.4 5.8 1.7 0 0 0
    400 1927 1443.0 -31.6 7.6 2.2 0 0 0
    450 1853 1334.0 -44.2 9.4 2.7 0 0 0
    500 1781 1232.0 -59.2 11.3 3.3 0 0 0
    550 1710 1137.0 -77.1 13.4 3.9 0 0 0
    600 1643 1048.0 -97.8 15.6 4.5 0 0 0
    650 1577 966.0 -121.8 17.9 5.2 0 0 0
    700 1514 890.0 -149.3 20.4 5.9 0 0 0
    750 1453 820.0 -180.6 23.0 6.7 0 0 0
    800 1395 756.0 -216.0 25.8 7.5 0 0 0





    I calculated 16” 6.5 Grendel, 123 grain bullet, 2425 FPS with .510 BC and scope 2.75” over bore. I used the 100 yard zero.



    Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
    0 2425 1606.0 -2.8 0.0 0.0 0 0 0
    50 2342 1498.0 -0.6 1.1 0.3 0 0 0
    100 2261 1396.0 0.0 0.0 0.0 0 0 0
    150 2181 1300.0 -1.1 0.7 0.2 0 0 0
    200 2103 1208.0 -4.1 1.9 0.6 0 0 0
    250 2027 1122.0 -9.0 3.4 1.0 0 0 0
    300 1953 1041.0 -16.0 5.1 1.5 0 0 0
    350 1880 965.0 -25.4 6.9 2.0 0 0 0
    400 1809 893.0 -37.1 8.9 2.6 0 0 0
    450 1739 826.0 -51.6 10.9 3.2 0 0 0
    500 1672 764.0 -68.9 13.2 3.8 0 0 0
    550 1607 706.0 -89.3 15.5 4.5 0 0 0
    600 1545 652.0 -113.1 18.0 5.2 0 0 0
    650 1485 602.0 -140.5 20.6 6.0 0 0 0
    700 1427 556.0 -171.9 23.4 6.8 0 0 0
    750 1372 514.0 -207.5 26.4 7.7 0 0 0
    800 1320 476.0 -247.8 29.6 8.6 0 0 0
    Last edited by VASCAR2; 01-11-2018, 02:37 AM.

    Comment

    • VASCAR2
      Chieftain
      • Mar 2011
      • 6219

      #3
      Here are the results for an 18” 6.5 Grendel, 123 grain bullet 2480 FPS, .510 BC scope 2.75” over bore. I used 100 yard zero.


      Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
      0 2480 1680.0 -2.8 0.0 0.0 0 0 0
      50 2396 1568.0 -0.6 1.2 0.3 0 0 0
      100 2314 1462.0 0.0 0.0 0.0 0 0 0
      150 2233 1362.0 -1.0 0.6 0.2 0 0 0
      200 2154 1268.0 -3.8 1.8 0.5 0 0 0
      250 2077 1178.0 -8.4 3.2 0.9 0 0 0
      300 2001 1094.0 -15.0 4.8 1.4 0 0 0
      350 1927 1014.0 -23.9 6.5 1.9 0 0 0
      400 1855 940.0 -35.0 8.4 2.4 0 0 0
      450 1784 870.0 -48.7 10.3 3.0 0 0 0
      500 1716 804.0 -65.1 12.4 3.6 0 0 0
      550 1650 743.0 -84.5 14.7 4.3 0 0 0
      600 1586 687.0 -107.0 17.0 5.0 0 0 0
      650 1524 634.0 -133.1 19.5 5.7 0 0 0
      700 1464 586.0 -162.8 22.2 6.5 0 0 0
      750 1408 541.0 -196.7 25.0 7.3 0 0 0
      800 1354 500.0 -234.9 28.0 8.2 0 0 0
      Last edited by VASCAR2; 01-11-2018, 04:01 AM.

      Comment

      • VASCAR2
        Chieftain
        • Mar 2011
        • 6219

        #4
        At 300 yards 7.62 has a drop 4.3 MOA

        At 300 yards 6.5G 16”. drop 5.1

        At 300 yards 6.5G 18”. drop 4.8

        At 300 yards 6.5G 20”. drop 4.7



        At 500 yards 7.62 has a drop of 11.3 MOA

        At 500 yards 6.5G 16”. drop of 13.2

        At. 500 yards 6.5G 18”. drop of 12.4

        At 500 yards. 6.5G. 20” drop of 12.2


        At 800 yards. 7.62 drop of 25.8. MOA

        At 800 yards. 6.5G 16”. drop of 29.6.

        At 800 yards. 6.5G 18” drop of 28.0

        At 800 yards. 6.5G. 20”. drop of 27.5

        Depending on load in 223/5.56 even with 77 grain SMK I think the 6.5 Grendel would still be closer. A 20” 6.5 Grendel would be closer to the 7.62 175 grain SMK.
        Last edited by VASCAR2; 01-11-2018, 02:47 AM.

        Comment

        • VASCAR2
          Chieftain
          • Mar 2011
          • 6219

          #5
          Last edited by VASCAR2; 01-11-2018, 03:29 AM.

          Comment

          • VASCAR2
            Chieftain
            • Mar 2011
            • 6219

            #6
            Here is 223/5.56 with 77 grain Sierra Match King, I estimated velocity about 2800 FPS out of an 18” barrel, .362 BC, 2.75” scope over bore. I used 100 yard zero.


            Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
            0 2800 1340.0 -2.8 0.0 0.0 0 0 0
            50 2674 1222.0 -0.8 1.5 0.4 0 0 0
            100 2551 1113.0 0.0 0.0 0.0 0 0 0
            150 2432 1011.0 -0.6 0.4 0.1 0 0 0
            200 2316 917.0 -2.6 1.3 0.4 0 0 0
            250 2202 829.0 -6.3 2.4 0.7 0 0 0
            300 2092 749.0 -11.8 3.7 1.1 0 0 0
            350 1986 674.0 -19.2 5.2 1.5 0 0 0
            400 1882 606.0 -28.9 6.9 2.0 0 0 0
            450 1783 543.0 -41.0 8.7 2.5 0 0 0
            500 1687 487.0 -55.8 10.7 3.1 0 0 0
            550 1596 435.0 -73.7 12.8 3.7 0 0 0
            600 1509 389.0 -95.1 15.1 4.4 0 0 0
            650 1426 348.0 -120.2 17.7 5.1 0 0 0
            700 1350 312.0 -149.6 20.4 5.9 0 0 0
            750 1279 280.0 -183.8 23.4 6.8 0 0 0
            800 1216 253.0 -223.3 26.7 7.8 0 0 0
            Last edited by VASCAR2; 01-11-2018, 03:00 AM.

            Comment

            • VASCAR2
              Chieftain
              • Mar 2011
              • 6219

              #7
              When I posted the 77 grain results I forgot this is not the bullet used with the Leupold scope. In the QA CS advised the scope is calibrated for 62 grain FMJ BC .302 at 2970 FPS. Leupold uses 50 yard zero but I used 100 yard zero scope 2.75” over bore.


              Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
              0 2970 1214.0 -2.8 0.0 0.0 0 0 0
              50 2813 1089.0 -0.8 1.6 0.5 0 0 0
              100 2662 975.0 0.0 0.0 0.0 0 0 0
              150 2516 871.0 -0.4 0.3 0.1 0 0 0
              200 2374 776.0 -2.2 1.0 0.3 0 0 0
              250 2237 689.0 -5.5 2.1 0.6 0 0 0
              300 2105 610.0 -10.6 3.4 1.0 0 0 0
              350 1977 538.0 -17.6 4.8 1.4 0 0 0
              400 1854 473.0 -26.9 6.4 1.9 0 0 0
              450 1736 415.0 -38.7 8.2 2.4 0 0 0
              500 1624 363.0 -53.4 10.2 3.0 0 0 0
              550 1519 317.0 -71.4 12.4 3.6 0 0 0
              600 1420 278.0 -93.1 14.8 4.3 0 0 0
              650 1329 243.0 -119.2 17.5 5.1 0 0 0
              700 1248 214.0 -150.2 20.5 6.0 0 0 0
              750 1177 191.0 -186.8 23.8 6.9 0 0 0
              800 1117 172.0 -229.6 27.4 8.0 0 0 0


              I decided to run the same data with 50 yards zero to see how much change it makes.


              Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
              0 2970 1214.0 -2.8 0.0 0.0 0 0 0
              50 2813 1089.0 0.0 0.0 0.0 0 0 0
              100 2662 975.0 1.6 -1.5 -0.4 0 0 0
              150 2516 871.0 2.0 -1.3 -0.4 0 0 0
              200 2374 776.0 1.1 -0.5 -0.1 0 0 0
              250 2237 689.0 -1.5 0.6 0.2 0 0 0
              300 2105 610.0 -5.7 1.8 0.5 0 0 0
              350 1977 538.0 -11.9 3.3 0.9 0 0 0
              400 1854 473.0 -20.4 4.9 1.4 0 0 0
              450 1736 415.0 -31.4 6.7 1.9 0 0 0
              500 1624 363.0 -45.2 8.6 2.5 0 0 0
              550 1519 317.0 -62.4 10.8 3.2 0 0 0
              600 1420 278.0 -83.4 13.3 3.9 0 0 0
              650 1329 243.0 -108.6 16.0 4.6 0 0 0
              700 1248 214.0 -138.8 18.9 5.5 0 0 0
              750 1177 191.0 -174.6 22.2 6.5 0 0 0
              800 1117 172.0 -216.6 25.9 7.5 0 0 0

              Here is the 16” 6.5 Grendel data 50 yard zero, 123 grain bullet, 2425 FPS, 2.75” over bore.


              Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
              0 2425 1606.0 -2.8 0.0 0.0 0 0 0
              50 2342 1498.0 0.0 0.0 0.0 0 0 0
              100 2261 1396.0 1.1 -1.1 -0.3 0 0 0
              150 2181 1300.0 0.6 -0.4 -0.1 0 0 0
              200 2103 1208.0 -1.8 0.9 0.2 0 0 0
              250 2027 1122.0 -6.1 2.3 0.7 0 0 0
              300 1953 1041.0 -12.6 4.0 1.2 0 0 0
              350 1880 965.0 -21.4 5.8 1.7 0 0 0
              400 1808 893.0 -32.6 7.8 2.3 0 0 0
              450 1739 826.0 -46.4 9.8 2.9 0 0 0
              500 1672 764.0 -63.2 12.1 3.5 0 0 0
              550 1607 706.0 -83.0 14.4 4.2 0 0 0
              600 1545 652.0 -106.2 16.9 4.9 0 0 0
              650 1485 602.0 -133.1 19.5 5.7 0 0 0
              700 1427 556.0 -163.9 22.4 6.5 0 0 0
              750 1372 514.0 -199.0 25.3 7.4 0 0 0
              800 1320 476.0 -238.7 28.5 8.3 0 0 0
              Last edited by VASCAR2; 01-11-2018, 03:55 AM.

              Comment

              • VASCAR2
                Chieftain
                • Mar 2011
                • 6219

                #8
                Here is comparison 62 grain FMJ to 16” 6.5 Grendel both with 50 yard zero. I decided to add in the 7.62 with 50 yard zero and the 18” 6.5 Grendel.


                300 yards 5.56. 1.8 MOA

                300 yards 6.5G. 4.0 MOA
                16” barrel

                300 yards 7.62. 3.1 MOA

                300 yards 6.5G. 3.6 MOA
                18” barrel


                500 yards 5.56. 8.6. MOA

                500 yards 6.5G. 12.1 MOA
                16” barrel

                500 yards 7.62. 10.2 MOA

                500 yards 6.5G. 11.3 MOS
                18” barrel


                800 yards 5.56. 25.9 MOA

                800 yards 6.5G. 28.5 MOA
                16” barrel

                800 yards 7.62. 24.8 MOA

                800 yards 6.5G. 26.9 MOA
                18” barrel
                Last edited by VASCAR2; 01-11-2018, 04:20 AM.

                Comment

                • RANGER
                  Warrior
                  • Oct 2016
                  • 102

                  #9
                  Wow, ask and ye shall receive!


                  Looks like the scope I have should be “close enough”

                  Thanks for the data!

                  Comment

                  • VASCAR2
                    Chieftain
                    • Mar 2011
                    • 6219

                    #10
                    I decided to run the numbers on the 7.62 with 50 yard zero. I was bored and was curious, so I decided to share. lol


                    Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
                    0 2575 2576.0 -2.8 0.0 0.0 0 0 0
                    50 2487 2403.0 0.0 0.0 0.0 0 0 0
                    100 2401 2239.0 1.3 -1.3 -0.4 0 0 0
                    150 2316 2085.0 1.1 -0.7 -0.2 0 0 0
                    200 2233 1938.0 -0.7 0.3 0.1 0 0 0
                    250 2152 1800.0 -4.2 1.6 0.5 0 0 0
                    300 2073 1669.0 -9.7 3.1 0.9 0 0 0
                    350 1995 1546.0 -17.1 4.7 1.4 0 0 0
                    400 1919 1431.0 -26.7 6.4 1.9 0 0 0
                    450 1845 1322.0 -38.7 8.2 2.4 0 0 0
                    500 1773 1221.0 -53.3 10.2 3.0 0 0 0
                    550 1703 1127.0 -70.6 12.3 3.6 0 0 0
                    600 1635 1039.0 -90.9 14.5 4.2 0 0 0
                    650 1570 957.0 -114.5 16.8 4.9 0 0 0
                    700 1507 882.0 -141.6 19.3 5.6 0 0 0
                    750 1446 813.0 -172.5 22.0 6.4 0 0 0
                    800 1389 750.0 -207.6 24.8 7.2 0 0 0


                    Here is the data for 18” 6.5 Grendel with 50 yard zero


                    Range Velocity Energy Trajectory Come Up (MOA) Come Up (MILS) Wind Drift Wind Drift (MOA) Wind Drift (MILS)
                    0 2480 1680.0 -2.8 0.0 0.0 0 0 0
                    50 2396 1568.0 0.0 0.0 0.0 0 0 0
                    100 2314 1462.0 1.2 -1.2 -0.3 0 0 0
                    150 2233 1362.0 0.8 -0.5 -0.1 0 0 0
                    200 2154 1268.0 -1.3 0.6 0.2 0 0 0
                    250 2077 1178.0 -5.4 2.1 0.6 0 0 0
                    300 2001 1094.0 -11.4 3.6 1.1 0 0 0
                    350 1927 1014.0 -19.6 5.4 1.6 0 0 0
                    400 1855 940.0 -30.2 7.2 2.1 0 0 0
                    450 1784 870.0 -43.3 9.2 2.7 0 0 0
                    500 1716 804.0 -59.1 11.3 3.3 0 0 0
                    550 1650 743.0 -77.8 13.5 3.9 0 0 0
                    600 1586 687.0 -99.8 15.9 4.6 0 0 0
                    650 1524 634.0 -125.2 18.4 5.4 0 0 0
                    700 1464 586.0 -154.4 21.1 6.1 0 0 0
                    750 1408 541.0 -187.6 23.9 6.9 0 0 0
                    800 1354 500.0 -225.2 26.9 7.8 0 0 0
                    Last edited by VASCAR2; 01-11-2018, 04:11 AM.

                    Comment

                    • scroder
                      Unwashed
                      • Dec 2016
                      • 23

                      #11
                      I do quite a bit of long distance shooting. BDC reticles are about only good for hunting out to 300y or so. Other than that, the BDC will never truly match what you are shooting due to weather, elevation, atmosphere, etc. Better to just get turrets and learn to dial for correct distance instead of relying on something that will be off 90% of the time.

                      Comment

                      • LR1955
                        Super Moderator
                        • Mar 2011
                        • 3355

                        #12
                        Originally posted by RANGER View Post
                        I have a Leupold Mk6 1-6 CMR (7.62) scope that I was thinking of using on my 16".

                        Two questions....

                        1) Will the subtensions that are set for the 7.62 (which I'm assuming is M118) be close to the 6.5G ? Or would the 5.56 be a closer match?

                        2) if the basis of this rifle is to ring steel at 300-800 yards would I be better off with 18"? What range does the extra 2" matter?
                        Ranger:

                        Seems to me with a 6X optic using a Christmas tree reticle that the optic was made for the various 7.62 service carbines popping up. Thus M-80. Ought to be a decent match up to an effective range for a 6X optic which is probably pushing it past 300.

                        I have the very first model of this optic that Leupold made about twenty years ago when SOCOM was thinking about a accurate 5.56 carbine for sniper team observers. The magnification is so low that precision was out of the question past 300 yards when using the dial, let alone a hold off. It really wouldn't matter if you put it on a 7.62 and shot 118 or M-80 or you kept it on a 5.56 and shot any of the 5.56 rounds. Honestly, you had a real hard time with a sight picture past about 300 due to the low magnification.

                        You want a match up for the Grendel? Find a reticle for the old M-852. I did just that with a scope that Night Force made some years ago using their 'velocity' reticle. You could choose between three reticles. One for low velocity, one for mid velocity, and hone for high velocity. I chose the low velocity and it was about a half minute from my Grendel loads at 600. The optic is a 10X which allowed me to get to 600. 6X with a tactical optic? Probably not.

                        So maybe the real issue is the magnification of your optic? Get a 10X and you are still pushing it at 800. 6X won't cut it in most environmental conditions at 800.

                        LR55
                        Last edited by LR1955; 01-11-2018, 03:58 PM.

                        Comment

                        • zcostilla
                          Warrior
                          • Aug 2017
                          • 110

                          #13
                          I have a question, and it's how good is good enough? It's a question we all ask at some point, especially when building something, anything. I asked it when putting together my Grendel under budget constraints, and had to settle on a Bear Creek Arsenal barrel& BCG, and a cheaper Vortex 2-7 scope. These will probably get upgraded, depending on how much I fall in love with the Grendel cartridge.

                          In your case, this scope is deemed good enough, and I completely get it. It has good glass, and is good for moderate ranges, especially for hunting. But if you're target shooting, and have a log book, then is the guesstimation of the reticle good enough? It might be, and then everything Im about to describe is completely overboard and academic, and would be a waste of time.

                          But I know me, and I'd use a ballistics app to calculate the MOA value for each subtension on the reticle, and then calculate the actual bullet drops for my commonly used loads at those MOA subtensions. And then Id paste the printouts inside the front cover of my range log. And then I'd use my first couple range sessions validating those numbers. And then I'd feel more comfortable when target shooting offhand and if I had to hunt with it, I'd also feel better about those guesstimations. (This is exactly what I have to do after finding which ammo my Gendel will like the best).

                          But it's all based upon the value you place on time/resources, and how good is good enough, and only you can make that decision. And it's no knock if you decide it's good enough as is, because you will have saved a lot of time and money.

                          On a side note: I only wish I was this anal about my woodworking, because I'm not, and prefer function over form, so good enough for me is based upon how well something works and not how pretty it looks. Needless to say, my wife wasn't thrilled about my homemade desk, and bought a replacement a year later when she couldn't stand looking at it. And I absolutely hate it because it's not very functional to me, but it looks nice, and a happy wife means more approved time for the things I love, when I'm well enough to do them. And I absolutely can't seem to get trim dine to my own satisfaction, so that job gets hired out.
                          -Zac

                          Husband, Father, Veteran. Grateful for my redemption.

                          Comment

                          • StoneHendge
                            Chieftain
                            • May 2016
                            • 2009

                            #14
                            Burris has a great reticle analysis tool on their website:



                            This will obviously work with any of their BDC type reticles but should also work for any standard 556/308 type reticle that has the same distance hash marks. It allows you to go in and manually enter your velocity/weight/bc etc. and you can also input your environmentals. It will then give you yardage at the hash marks
                            Let's go Brandon!

                            Comment

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