Range Report: AR-Comp & Amax 123

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Range Report: AR-Comp & Amax 123

    Wee Dogies!

    You gotta love these affordable, AR-Stoner (E.R. Shaw) barrels. Once again, these Amax 123 gr bullets make even a mediocre shot like me, look good. Combined with Alliant's new AR-Comp powder, they were fairly accurate across 2gr of powder variation. AR-Comp by weight delivers more velocity than 8202. Like 8202, it's a small granule extruded powder, but not as small as 8202 and less dense so you can't pack as much in by weight.

    That having been said. Range conditions were ideal as I head toward the weekend when we tear it down. So ideal that, cough I had to use up some of my cough banked 168 hours of sick leave cough cough. When I drove the Mrs to the park-n-ride, as she exuded jealousy, the bank said it was 59 degrees out and with the windows down the whole way, it combined with the low humidity to make me eager for the range to open a 9 AM. My only regret is that I didn't load up many more other calibers I'm working on to make it a longer range day. Yep, we're definitely starting the slow slide toward our 6 months of winter. We had a longer duration winter than usual last year, then maybe 2 weeks of spring and boom! Hot weather set upon us like a lot of the nation. Hopefully the autumn will be longer. The range is closed the next two weekends.

    Anyway, my gut feeling is this powder, despite being very powerful for it's burn rate, is a titch too slow for this weight range of bullet in this caliber. For folks considering hunting with 140gr bullets, I'd bet a dollar to a doughnut it would fall smack dab in the middle of the sweet spot. If it gets your interest up, look at the recipes for .223, .308, .22-250 and .223 WSSM on the Alliant web page. The velocity yields are unbelievable and that from a wide temperature (claimed) powder.

    Here's the four 5-shot strings from my 24" barrel and their respective 100 yard groups. I was mainly focused upon the chronometer, but tickled pink with the groups for a range hack like me.





    They compare favorably to my first at bat with them last May Here.

    If you like to play with alternate powders in between sessions of shooting the same, old, reliable stuff, consider a bottle of AR-Comp.

    Respectfully submitted

    Hoot
    Last edited by bwaites; 08-10-2011, 11:23 PM. Reason: 24 not 23
  • bwaites
    Moderator
    • Mar 2011
    • 4445

    #2
    Nicely done, thanks for the information!

    Comment

    • Variable
      Chieftain
      • Mar 2011
      • 2403

      #3
      +1! Thanks for sharing the info!
      Life member NRA, SAF, GOA, WVSRPA (and VFW). Also member WVCDL. Join NOW!!!!!
      We either hang together on this, or we'll certainly HANG separately.....

      Comment

      • terrywick4

        #4
        This looks like an outstanding powder for the grendel. Any signs of pressure? How do you think it would do with 107 smk? I like the velocity of the 28.5 and the grouping aint terrible, but I haven't had much luck with compressed loads in the past with other calibers seems oal is hard to hold and control over time unless one puts a good crimp on them. Is great range report is definetly worth investigating. Was pretty set on 8208 but now will have to do some comparing once golf season is done.

        Comment


        • #5
          Originally posted by terrywick4 View Post
          This looks like an outstanding powder for the grendel. Any signs of pressure? How do you think it would do with 107 smk? I like the velocity of the 28.5 and the grouping aint terrible, but I haven't had much luck with compressed loads in the past with other calibers seems oal is hard to hold and control over time unless one puts a good crimp on them. Is great range report is definetly worth investigating. Was pretty set on 8208 but now will have to do some comparing once golf season is done.
          As I said in part one with the NBT 120s, I do not use really compressed loads due to the fact that they tend to stray from the predictable ballistic curve. That 28.5 load was barely breaking granules and that's why I stopped, despite zero pressure signs, unlike 8208 as you get near the top. It being slightly faster than the AR-Comp, it would be a perfect match for a 107 SMK, but I'm speculating as I haven't tried lighter bullets than the 120s with AR-Comp. I am sincere in saying that it looks to be more suited for heavier bullets in this caliber, but life is for learning. Getting back to that 28.5 load. There was not enough compression so as to resist the bullet staying seated at a particular COL. It felt as if I could have gone to 29 and possibly 29.5 before that degree of compressed load occurred. As soon as I heard granules cracking with the stethoscope, I stopped increasing the charge. It turns on much more mellow than 8208 as far as the actual ignition felt through the gun.

          I have not played with primers at all. I like the Rem 7 1/2's because they're very hot for igniting slower powders. Perhaps a slightly cooler primer with 8208 would make a difference. Right now, I have two other calibers, I'm experimenting with and writing reports on, but the Grendel is always guaranteed to improve my mood when the other two are being difficult. I believe it is the epitome of all around performance on an AR15 platform, without going to extremes.

          Hoot

          Comment

          • rasp65
            Warrior
            • Mar 2011
            • 660

            #6
            Hoot As usual the data you provided is in an excellent format and well presented. Great work.

            Comment


            • #7
              Hi Hoot, I have a 24" 1-8 lother walther SAOD upper over an RRA lower. I have gotten similar velocity, 2506 with 29.4 gr of Re15 and .610 five shot groups with the 123 amax. I have found most alliant powders to be very sensitive to only one tenth grain increments, but if you hit the sweet spot they are the best. I will try the ar-comp.
              Rich

              Comment

              • Drifter
                Chieftain
                • Mar 2011
                • 1662

                #8
                I tested AR-Comp with 123gr Lapua Scenars and got respectable results from an 18" Satern barrel (Grendel chamber). Accuracy tightened up when overall cartridge length was shortened to 2.250". At 2.260", velocity (and pressure) was higher, but accuracy not as consistent.

                The target below shows a 5-round group at 200 yards on 9/27 that prompted me to load more at the same length. Then four 3-shot groups were fired on 9/28. (Extra hole below 1st bullseye was from previous day.) The results were not only a testament to the powder, but also to the repeatability of the Bobro mount, which was removed / replaced twice during the four groups. All except 1 of the 12 shots were inside of the inner 1.5" circle (~0.75-moa @ 200 yards).

                Hopefully, details of the load will show in the pic below:





                *These loads were safe in my rifle. Use of load data is at your own risk.*
                Drifter

                Comment

                • sneaky one
                  Chieftain
                  • Mar 2011
                  • 3077

                  #9
                  You did a Great job = Hoot and Drifter, nice pics too. I've been leaning towards 8208-- and- or ar-comp.,,, or alliant mr 2000. Drifter- nice rifle! Mine is boring in comparison. Yet I will use mine for mostly hunting, and the off chance of a survival scenario- aka- if I need a beatin stick, or a boat paddle, it's hired !
                  Last edited by sneaky one; 09-30-2011, 02:05 AM.

                  Comment


                  • #10
                    Great post. I am looking forward to getting back out with the Grendel before too long.

                    Comment


                    • #11
                      Originally posted by sneaky one View Post
                      You did a Great job = Hoot and Drifter, nice pics too. I've been leaning towards 8208-- and- or ar-comp.,,, or alliant mr 2000. Drifter- nice rifle! Mine is boring in comparison. Yet I will use mine for mostly hunting, and the off chance of a survival scenario- aka- if I need a beatin stick, or a boat paddle, it's hired !
                      Pretty hard to beat 8208 for extruded powder with this caliber and its more available than AR-Comp at the moment. It also delivers more velocity, accurately than AR-Comp due to higher loading density. If you want to shoot the 140s, AR-Comp is a better choice in rifle length barrels from being a slightly slower burner. If you get some AR-Comp, do try different primers with it. I did a head-to-head comparison with the same charge weight in my LAR-8 .308 and got my best groups with inexpensive CCI 200s, over Federal 210M, Remington 9 1/2 and WLR, all of which run hotter than the CCIs. Reasonable SD as well, which was indeed a surprise. All produced velocities within 25 fps of one another, with the CCIs being the slowest, but there was no comparison to the accuracy edge of the 200s. I realize in the Grendel, those would be CCI 400s, WSR, 7 1/2 and 205M. When I work up my deer season load in a week of so, I will try the same experiment in the Grendel, though I already have an NBT 120 load that shoots sub-MOA, but I am considering a monolithic bullet to avoid eating lead and given their predictable expansion. Just not sure which one. I know there are members who are very happy with the TTSX in a slightly lighter bullet running higher velocity for reliable expansion at longer distances.

                      Hoot

                      Comment


                      • #12
                        Hoot,

                        You have 2.29 listed for the OAL. How far off of the lands are you with that? Have you guys tried to mess with the length at all, or how close are you putting them?

                        Comment


                        • #13
                          Originally posted by Sniper20 View Post
                          Hoot,

                          You have 2.29 listed for the OAL. How far off of the lands are you with that? Have you guys tried to mess with the length at all, or how close are you putting them?
                          About .03 inches closer than 2.26.

                          Seriously, you really should measure your particular chamber as there are variances from one to the next and yeah, it's important to know your particular chamber's measurement as opposed to someone else'. I will try to remember to look at my notebook for the Grendel when I get home from work, but it's probably going to be a dimension unique to my .300 neck Grendel chamber.

                          Hornady does make a 6.5 Grendel case for the Overall Chamber Length Gauge. A tool I recommend every reloader have, or a DIY version like this. Starts at post #7.

                          Hoot

                          Comment


                          • #14
                            I know that each chamber is different. My question was how far off did you set the ogive? Most bullet like to have about the same amount of jump from the ogive to the lands. I was just curious as most bullets like the same amount of jump... Did you set .005 back, .010 back, .015? Just trying to help get a good reference point for mine...

                            Comment


                            • #15
                              Originally posted by Sniper20 View Post
                              I know that each chamber is different. My question was how far off did you set the ogive? Most bullet like to have about the same amount of jump from the ogive to the lands. I was just curious as most bullets like the same amount of jump... Did you set .005 back, .010 back, .015? Just trying to help get a good reference point for mine...
                              I just remembered to check my notebook. For an average of 10 bullets from the same box, the 123 Amax hits the lands with authority (not mushy) at 2.296 inches COL. Longer than either the 100 or 120 NBT.

                              Hoot

                              Comment

                              Working...
                              X