Range Report Swift Scirocco 130

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  • RangerRick

    Range Report Swift Scirocco 130

    I've been working up a load for the 130 Swift Scirocco hunting bullet.

    The bullet has an excellent reputation in other 6.5mm guns.

    Alexander Arms sells loads with this bullet. Gel test pictures are on their web site for the 130 Scirocco.

    The bullet tumbled in less than two inches, did not exit the last get block and stayed intact while mushrooming well. To see the picture, go to the Alexander Arms web site and select "online store" under "Products", select ammunition under Grendel, then choose the second picture.

    The manufacturer claims a ballistic coefficient of .571. If true, that's an excellent BC. Some say the BC is more like .540, but even that is very good.

    The bullet is usually used in guns with higher mv's than the Grendel is capable of with this bullet, so the BC may be even less at Grendel speeds.

    The barrel used for this was a Satern 20 inch, 1 in 8.5.

    Speeds were measured by chrono 15 feet from the muzzle.

    I started out using the Alexander Arms load data. I had Winchester 748 and AA2520 on hand, so I used them.

    2520 was a little better than the 748. I also had some LeveRevolution, so I gave it a try since it's a slower powder.

    The mv's of 2300+ fps were significantly better than the other two powders I tried.

    LeveRevolution is pretty dense too, so it leaves plenty of room in the case for the long 130 grain bullets.

    If you calculate energy with the lower BC (.540) this doesn't give as much energy as the 123 AMax but the difference gets less with range.

    Since the Scirocco is designed as a hunting bullet it holds together well and the extra weight will help it punch through bone and tough hides. It will expand at mv's down to 1400 fps so it's functional at ranges out to 750 yards.

    The biggest disadvantage is price, it cost's nearly double the price of the AMaxes.

    It's also very accurate. It has a polymer tip to increase BC and promote expansion, but it's very tough compared to some others polymer tips I've used.

    C.O.L. was 2.260 for all loads.

    One caveat, the data was taken with small groups of shots since I was working up loads. I'll follow up later with some data from a larger group of loads with 30.6 grains, and measure some drops to see if it tracks with the advertised BC.

    Powder Average MV
    (grains) (FPS)


    Win 748

    29.0 2237
    ---------------------

    AA2520

    28.0 2256
    ---------------------

    LeveRevolution

    30.2 2282

    30.4 2288

    30.5 2295

    30.6 2310



    RR

  • #2
    Nice report daddy. After talking with Bob Reynolds of Templar about YutYut's 20" Grendel, I learned that it has a Bartlein progressive twist barrel, starting at 1/8.75, then 1/8 I think. Bartlein can do whatever crazy progressive twist rate you can think of.

    My thoughts on this for a while have been to start out with a slow twist, like 1/10 or even 1/11 for the first 5-7", then increase to 1/9, then 1/8 for gyroscopic stability with the longer pills.

    The reasoning is this: A straighter twist initially will disperse higher pressures down the tube with less resistance from tight rifling. As the pressure builds slowly, the curve will be flatter on the bell shape, and allow for more burn time to get the long projectiles going without sharp spikes in the first 5-7" of barrel.

    It could be misguided thinking on my part, but I noticed that the guys shooting the GS solids and other bullets of that type with driving bands have progressive twists.

    Bob Said he has a bunch of those 1/8.75-1/8 Bartleins, so I'm really thinking about one to test the hypothesis.

    Comment

    • RangerRick

      #3
      LRRPF52,

      Bob will steer you right. He built my Grendel.

      That sounds plausible about the progressive barrels. I'll be curious to see if it works.

      I left out that these loads shot less than 1 MOA. But there again, I need to shoot a lager group with that powder load to get better numbers.

      RR

      Comment


      • #4
        Thanks so much for the data with LeveRevolution I will try it after deer season. I woud take that 1400fps expansion with a grain of salt. 1600-1700fps expansion more realistic.

        Comment

        • RangerRick

          #5
          Originally posted by hm2 clark View Post
          Thanks so much for the data with LeveRevolution I will try it after deer season. I woud take that 1400fps expansion with a grain of salt. 1600-1700fps expansion more realistic.
          Thanks for the info, that makes it effective out to between 450 to 550 yards, calculated at a BC of .540.


          RR

          Comment

          • IndyGrendel63

            #6
            Originally posted by RangerRick View Post
            LRRPF52,

            Bob will steer you right. He built my Grendel.

            That sounds plausible about the progressive barrels. I'll be curious to see if it works.

            I left out that these loads shot less than 1 MOA. But there again, I need to shoot a lager group with that powder load to get better numbers.

            RR
            Who is Bob and does he still build Grendels? I am thinking about another one and I want something better than I have now.

            Comment

            • RangerRick

              #7
              Originally posted by IndyGrendel63 View Post
              Who is Bob and does he still build Grendels? I am thinking about another one and I want something better than I have now.
              Bob Reynolds at Templar Consulting:

              (877) 878-2334
              bobjr@templarconsultingllc.com

              He builds very nice custom guns at reasonable prices. Many calibers at reasonable prices.

              RR

              Comment

              • Drifter
                Chieftain
                • Mar 2011
                • 1662

                #8
                Scirocco II's resulted in severe copper fouling in my barrel. And nothing would shoot right afterwards (until the barrel was thoroughly cleaned).

                Results vary I suppose, but a google search using "Scirocco II copper fouling" revealed that I'm not the only one.
                Drifter

                Comment

                • txgunner00
                  Chieftain
                  • Mar 2011
                  • 2070

                  #9
                  Originally posted by Drifter View Post
                  Scirocco II's resulted in severe copper fouling in my barrel. And nothing would shoot right afterwards (until the barrel was thoroughly cleaned).

                  Results vary I suppose, but a google search using "Scirocco II copper fouling" revealed that I'm not the only one.
                  That's due to the fact the jackets are pure copper and not gilding metal like most jackets are. I spent about an hour on the phone with the owner a few years ago when I was trying to dial them in on several of my other rifles. He readily admits they are not a match bullet and they were never intended to be. They were designed to be a hunting bullet with high expansion, high weight retention and high penetration. In those parameters they perform very well.
                  NRA life, GOA life, SAF, and TSRA

                  "I ask, Sir, what is the militia? It is the whole people, except for a few public officials. To disarm the people is the best and most effectual way to enslave them."

                  George Mason, co-author, 2nd Amendment.

                  Comment

                  • RangerRick

                    #10
                    Originally posted by Drifter View Post
                    Scirocco II's resulted in severe copper fouling in my barrel. And nothing would shoot right afterwards (until the barrel was thoroughly cleaned).

                    Results vary I suppose, but a google search using "Scirocco II copper fouling" revealed that I'm not the only one.
                    That's interesting, folks have had the same problem with some of the Nosler's. Probably for the same reason mentioned buy TXgunner00, pure copper jackets. They work great but if you switch to another bullet, you have to shoot 10 rounds or so before you can get decent accuracy.

                    Lately, several of us have been experimenting with CFE 223. I've had great results with it for the Scirocco II's. I tried it because of muzzle velocity improvements others got, because I wasn't getting stellar velocities with any other powder.

                    I get about 90 feet per second better muzzle velocity out of it than LeveRevolution with the Scirocco's with a 20 inch barrel, and it burns cleaner.

                    The CFE stands for "Copper Fouling Eliminator." I didn't get it for that reason, but it might be another reason to use it with the Scirocco's and Noslers.

                    Supposedly, it was developed for the military for high rate of fire weapons. They put an additive in it to form an alloy of copper with what sticks to the barrel. The alloy is pretty brittle and gets blown out with the next shot, so they say.

                    I don't know what that does to accuracy, I haven't checked yet, but others have had good results.

                    The Scirocco's are too expensive for me to shoot every day, but for long range matches, where we might shoot 30 shots, and hunting, they would be great.

                    RR
                    Last edited by Guest; 05-20-2012, 04:14 PM. Reason: typo

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                    • #11
                      I had great luck in other cartidges with the original Scirocco, but couldn't get the Scirocco II to shoot. They changed the jacket material to get better expansion on game at reduced velocities.

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