I drank the cool-aid, and it was good!

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  • LRS_Ranger

    I drank the cool-aid, and it was good!

    Well, with all the hullabloo about 8208 I went in with a friend and got an 8 lb jug. Today I loaded from 27.8-29.2 grains in .2 grain increments. 123 AMAX, Lapua brass, CCI 450's, 2.270 COAL, and 1.5 thou of neck tension. I only got chrono info on the 29 and 29.2 charge weights, and they were 2605 and 2630 FPS average respectively. I hit a node on the head at 28 grains, and I and pretty close to another one at 29.0 grains. I'm glad it all worked out, because I have 8 lbs of the stuff. If it works as well as I have heard with 155's in the 308, I'll never use Varget again...

    I am also going to use my AMAX load to find a 123 Scenar load as well; a 2600 FPS+ Scenar would be the cat's ass...

    As a side note, the upper I'm using is a SAC build with a 20 inch Krieger bbl.

  • #2
    How do you feel about pressure at 29gr?

    Hodgdons max charge for a 123gr serial is 28.5.

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    • LRS_Ranger

      #3
      I was watching closely the whole way up... No primers were flat, did not have cratering of the primers, and everything looked normal. I realize that it's a little bit hot, but everything seems alright... I should probably drop down again and work up when I switch to Scenars though, just to be safe.

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      • #4
        Keep us in the loop.

        You ever shoot anything with those scenario?

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        • LRS_Ranger

          #5
          Yea, I've burned through almost half a box of 1000 of them... they don't shoot for crap at 100, but out at 300 and beyond they are awesome. If the Amax's shoot well at all distances, I will most likely shoot those exclusively after I use the rest of the box of Scenars.

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          • #6
            I think there is definitely something to the group tightness at 100 yards versus 200 yards. I just got in 500 of the 123 AMAX and was planning to pick up a Pound of the 8208 to try. This is good info to compare the 8208 with the 2520 at longer ranges. Keep the info coming. I'll post up what I find, also.
            Rick

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            • LRS_Ranger

              #7
              Next week I should be able to get out to the 600 yard... I am thinking that I am going to refine my load this weekend and bang some steel. After the 600 I'll post up how it worked.. For now I am going to stick with the AMAX, I'll mess with the Scenar's later.

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              • #8
                Originally posted by LRS_Ranger View Post
                Next week I should be able to get out to the 600 yard... I am thinking that I am going to refine my load this weekend and bang some steel. After the 600 I'll post up how it worked.. For now I am going to stick with the AMAX, I'll mess with the Scenar's later.
                Well? How did it go? I just got in 500 Sierra 123's, so now I can do a side-by-side of the 123 AMAX and the 123 Sierra. Just finishing up a month long shutdown so there has been no shooting for me in over a month. I'll post up info on the comparison soon.

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                • LRS_Ranger

                  #9
                  Update:
                  I have useful load with both AMAX's and Scenars. All loads are with CCI450's, Lapua brass, about 1.5 thou of neck tension.

                  123 Scenar, 28.4 of 2808, and 2.268 COAL 2630 FPS
                  123 AMAX, 28.5 of 2808, and 2.270 COAL 2625 FPS
                  I can get around .5-.6 inch average with the Amax at 100 yards, but the velocity is not always consistant. The batch of brass I was using for this load has been loaded about 4 or 5 times and I haven't annealed yet, so I am guessing that inconsistant neck tension could be the source of some of my problems there. When I took it to 600 yards, it seemed to shoot fairly consistant except for the low flyers. I am going to try this in newer brass, or anneal that batch and see if that clears up some of the problems. I really would like to like the Amax's as they are much cheaper than the scenars. With consistant velocity this would be fairly good load.

                  The scenars run EXTREMELY good extreme spread numbers (less than 10 FPS) but still shoot like crap at 100 yards. .7-.9 is fairly common. However, when you take them out to 600 they start to shine. Vertical at range is very good, with the bullets tracking in a line across the target due to wind. I had an occasional low shot, which I am owing to the fact that I threw the charges. Next time I am going to throw and trickle, and I bet that even the occasional 2 inch low shot will go away.

                  Just for kicks and giggles I threw together a few loads with 120 Nosler BT's and 28.5 of 8208. I only shot them at 100, but they went to the same point of impact as both the other loads. I only shot 3 rounds, but they were under an inch. Velocity was around 2590 average.

                  I really want to like the Amax's. They are so much cheaper that the Scenars, and have a similar BC. I am going to load them in fresh brass and see what I can make happen. If I can't clean up the extreme spread numbers though, I guess I will stay with the Scenars, unless I am trying to shoot something small close up. I would like to try some Nosler 120's with this powder as well. Maybe that will be my next experiment. The 120's shot extremely well with 2520 in my rifle.

                  -LRS
                  Last edited by Guest; 06-29-2011, 07:34 PM. Reason: Clarify and add new data

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                  • #10
                    I had an oppurtunity to take one of the Grendels out this past weekend to a BBQ and shoot. I loaded some 120 SMK's over 30.2 grains 2520 loaded to 2.220". I did not get to personally shoot these loads, because everyone else wanted to shoot it, but it was busting the crap out of 4" clay pigeons at 200 yards. No misses. Not exactly a technical report, but at least the loads did not appear to have any pressure issues. Temperature was 95 degrees. I plan to start refining my loads and have some 120's, 123 SMK's, and 123 AMAX to play with.

                    I usually don't chrono my loads until I find the nodes that group best. I used to frustrate the hell out of myself when I would get these great muzzle velocities, but the groups were poor.

                    I still plan to try some 8208, but since I got 8 lbs. of 2520, it may be a while. Lol.

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                    • #11
                      LRS_Ranger,

                      What magnification were you on when shooting at 100yds?

                      LRRPF52

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                      • LRS_Ranger

                        #12
                        I usually shoot for groups at 100 around 14X or so. I have a 6.5-20 Leupold Mk4. I've experimented with different settings, and that is the one that shoots best for me. When I'm actually shooting at real targets I typically use less magnification (around 10X) unless I'm much further away.

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                        • #13
                          LRS_Ranger,

                          I was just wondering if your groups at 100 would shrink if you dialed down to 10x or even lower. It doesn't make sense that the bullets would be unstable at 100, then tighten-up further out. I've heard the argument about bullet RPM and balancing out, but shot dispersal between a group of projectiles can't be stabilized by bullet rotational balance to the axis of flight...only individual projectiles can. In other words, even if they were somehow individually not optimally balanced, they would still print the same or better group dispersal at 100 than 200. I bet if you dialed down and tuned your focus, you would probably see tighter 100yd groups.

                          I found it much more difficult to shoot on higher magnification at 100yds. With a rifle rest using Velcro straps and a solid mechanism to lock the gun down, I have been able to do it when doing accuracy-testing for a manufacturer, but it required a lot of mental focus, and extreme attention to the fundamentals, even with the rest. This was for rifles with .5 MOA guarantee, so test targets had to be sent with each rifle. It's not so fun when you have a stack of 20 .338 LM rifles that have never been shot before, with $66 boxes of Lapua/10rds .338 LM, day after day. I always had the S&B PMII on 25x for those tests, which I normally would never do at 100. It was more convenient to keep it on 25x so I could measure the groups, versus dialing back and forth, or looking through a spotter. That's the only reason I think it stayed on 25x...

                          I don't know if you're using a rest or not, but it helps me to settle the gun each time, no matter what position I'm using. That get's me closer to natural point of aim when I do it, so it takes less time and less shooter input to keep the reticle true through the center of my aiming point.

                          The biggest factor that comes into play is overcoming the mental game of seeing negative effects of shooter input magnified on such a close target, and feeding into the positive loop feedback cycle it does on your mind and body, which can easily spiral downward when apprehension kicks in, then fear of the shot, fear restricts bloodflow, muscles start shaking...along with the reticle, causing more apprehension...more fear of failed performance...O2 loss to muscles...spiraling down...down...down...BLAM!!! "Where did that one go...?"

                          Experienced shooters will have a tighter shot group under these conditions due to successful and habitual practice with consistent positioning, trigger control, sight alignment, etc., but still not exploit the accuracy potential of their firearm. I have seen several shooters report this same phenomenon, where their 100yd groups weren't what they would like, but the rifle/ammo/optic/mount/shooter system proves to be exceptionally sub-MOA at distance well past 200. Without exception, I think every instance involved shooting at 100 on higher magnification than necessary.

                          LRRPF52
                          Last edited by Guest; 06-30-2011, 05:08 PM.

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                          • #14
                            LRS-
                            Finally gonna get a chance to check my loads tomorrow. I'll post up my 2520 results with the 120 SMK's. We can compare notes against the 8208.
                            Rick

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                            • LRS_Ranger

                              #15
                              I will try that. That's one thing that I have not tried to shrink my 100 yard scenar groups.

                              The way I've heard it explained as to why some bullets take longer to settle down, is to relate it to a child's top. Some do it more than others, and some hardly at all, but all tops, when initially spun, exhibit a bit of wobble till they gyroscopically stabilize and then continue to spin smoothly. Now picture the rifle bullet being spun out of the barrel by the rifling. That initial wobble is enough to deviate the bullet slightly from it's course. After the wobble stops though, the bullet stabilizes and flies as designed.

                              I'm always ready to try a new idea though, so I will give dialing down my magnification down a shot. (no pun intended... ) I do think that there is more than shooter mental stuff going on though, because the scenar is the only bullet that I can't get to group for crap. The 120 SMK's regularly shot into under half an inch for me when I was doing load development, and using the magnification I always have.

                              RStewart, I'll look forward to hearing your notes on the 120 2520 combo. It was a winner for me, but I had 1000 scenars so that's what I'm shooting. I'm interested in seeing how they work with 8208. I imagine similar to the 120NBT, which I got to almost 2600 over 28.5 gr of 8208.

                              -LRS

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