Berger 130 AR Hybrid OTM Tac's & CFE 223

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  • 1911man
    Warrior
    • May 2015
    • 482

    #16
    Originally posted by Fredman View Post
    Thanks. I was afeared of that. I really 8208 and have a bunch of it. But, a Berger bullet designed for ARs? Got to try it.
    Im betting you could still get good groups with XBR but probably not near the velocity you would get with Levr or CFE

    Comment

    • sneaky one
      Chieftain
      • Mar 2011
      • 3077

      #17
      This Really is a Cool bullet. Been checking it out online since it's inception. I would like to slice 1 lengthwise to see what's really under the skin. Tapers, & base units copper size , wt. etc.

      Anyone have an extra, or 2 to donate? I can check the viability of a 115-120 unit, while slicing 1 open. Open minds lead to great offerings.

      Sierra has the same idea in the OTM idea. Hunting version.
      Last edited by sneaky one; 01-26-2016, 01:52 AM.

      Comment

      • kmon
        Chieftain
        • Feb 2015
        • 2095

        #18
        Sneaky, pm me an address and will send you a few

        Comment

        • kmon
          Chieftain
          • Feb 2015
          • 2095

          #19
          Originally posted by 1911man View Post
          Im betting you could still get good groups with XBR but probably not near the velocity you would get with Levr or CFE
          Usually when bullet wieght and legnth increases a slower powder woeks best but sometimes good results can be had with faster burning powders. Have read many times on here though that 123 seems to be the upper end for best results with XBR. No reason to doubt some very experienced guys with the Grendel though

          Comment

          • sneaky one
            Chieftain
            • Mar 2011
            • 3077

            #20
            It's about keeping current, and an open mind on all that surrounds this 12-13 yr. old round. It's up to us- the many that like this caliber-size - etc.,,, and the willingness to accept the fact
            that a few will push Ahead on some subjects. Grrr Max is 1- Thoughts ?

            kmon, yeah all the known data is -proven. I busted a many myths on This round. Trial & Error is best for a Many,,- follow the herd -- is the rest. No problem either way. Buy a Grrr. ! Shoot.

            Team effort has always been my goal for the GRRRR gang, !!! Go!! Find something new ASAP.

            Comment

            • NugginFutz
              Chieftain
              • Aug 2013
              • 2622

              #21
              I returned to the range, today, and shot a couple of ten round strings of 30.6 gr. CFE223.

              Temps are 24 ' warmer (37 'F then, 61 'F today) and, not surprisingly, I saw an increase in MV. For the 24 'F increase, I picked up an average of 31 fps, or 1.3 fps per ' F.

              Same components as before: Hornady cases, CCI 450 primers, Berger 130 AR Hybrid OTM's, seated at 2.260".

              the first 10 round string went over the chronograph and resulted in the following:

              Code:
              #	FPS	FT-LBS	PF			
              10	2404	1668.51	312.52			
              9	2406	1671.28	312.78			
              8	2420	1690.79	314.6			
              7	2396	1657.42	311.48			
              6	2389	1647.75	310.57			
              5	2366	1616.17	307.58			
              4	2411	1678.24	313.43			
              3	2377	1631.24	309.01			
              2	2397	1658.8	311.61			
              1	2388	1646.37	310.44
              			
              Avg	StdDev	Min	Max	Spread	True MV (10' to chronograph)
              2395.4	16.1	2366	2420	54	2399
              Decent velocities and acceptable SD. At this speed and altitude, the round goes transonic at about 1250 yards and has excellent stability. With this barrel's 1:8 twist, it yields an impressive Miller Stability factor of just over 2.5, but even a 1:9 twist still yields a 2.0.

              Shooting the group at 100 yds. with the next 10 rounds proved challenging, as winds were steadily increasing. With winds at 20 mph and gusting to 27, the target stand was swaying significantly, causing the sight picture to move a full inch or more, so I had to time the shots as best I could.



              After the 7th shot, though, I cut my losses and was happy to get what I did.



              Shot at 100 yards. Grid is .10", so the full group size was just under 1", CTC, and the cluster of five runs right at .5" CTC at its widest.

              For the conditions, I think this was acceptable, especially since I could feel the table moving beneath me.

              Thanks for the read.
              Last edited by NugginFutz; 01-31-2016, 02:45 AM. Reason: Add data
              If it's true that we are here to help others, then what exactly are the others here for?

              Comment

              • JASmith
                Chieftain
                • Sep 2014
                • 1620

                #22
                That would be a bad 25 yard group under those conditions, but I'm guessing the target was a tad further out.
                shootersnotes.com

                "To those who have fought and almost died for it, freedom has a flavor the protected will never know."
                -- Author Unknown

                "If at first you do succeed, try not to look astonished!" -- Milton Berle

                Comment

                • 1911man
                  Warrior
                  • May 2015
                  • 482

                  #23
                  This is awesome data. Are you seeing any pressure signs at with this charge weight? I would imagine not since you are not even close the max charge for CFE and this size bullet. Good stuff man, keep it coming.

                  Comment

                  • NugginFutz
                    Chieftain
                    • Aug 2013
                    • 2622

                    #24
                    Originally posted by JASmith View Post
                    That would be a bad 25 yard group under those conditions, but I'm guessing the target was a tad further out.
                    Sorry, jasmith. 100 yds.
                    If it's true that we are here to help others, then what exactly are the others here for?

                    Comment

                    • NugginFutz
                      Chieftain
                      • Aug 2013
                      • 2622

                      #25
                      Originally posted by 1911man View Post
                      This is awesome data. Are you seeing any pressure signs at with this charge weight? I would imagine not since you are not even close the max charge for CFE and this size bullet. Good stuff man, keep it coming.
                      Not a single sign of pressure. My loads of 28.0 of 8208 pushing the 123 Amaxes show signs of flattened primers. Not so, these loads.
                      If it's true that we are here to help others, then what exactly are the others here for?

                      Comment

                      • NugginFutz
                        Chieftain
                        • Aug 2013
                        • 2622

                        #26
                        Originally posted by sneaky one View Post
                        This Really is a Cool bullet. Been checking it out online since it's inception. I would like to slice 1 lengthwise to see what's really under the skin. Tapers, & base units copper size , wt. etc.

                        Anyone have an extra, or 2 to donate? I can check the viability of a 115-120 unit, while slicing 1 open. Open minds lead to great offerings.

                        Sierra has the same idea in the OTM idea. Hunting version.
                        Sneaky -

                        Well, I finally got out to shoot the modified Berger AR Hybrids. Gotta say I wish Berger would make these in the 115gr neighborhood. The four bullets you modified weighed 112.6, 114.6 (2) and 114.9 grs. With a charge of 28.5 gr of IMR 8208 XBR, and seated to 2.260", the following velocities were recorded through a 22" BHW barreled rifle.

                        2694, 2700, 2764 and 2687 for an averaged MV of 2691 fps
                        Note: While I understand that the form factor will not be quite the same, being that you trimmed their length, it should still prove a reasonably close figure for these purposes.


                        SD = (W / 7000) / (D^2)
                        G7 BC = SD / G7 FF

                        Where:
                        W = weight in grains
                        D = bore diameter in inches
                        G7 FF (.928, from Berger's 130 AR Hybrid OTM data specs)

                        I calculated both original and new weights.
                        Code:
                        W	D	SD	G7 FF	G7 BC
                        130	0.264	0.266	0.928	[B]0.287[/B] (reference calculation)
                        114	0.264	0.234	0.928	[B][COLOR="red"]0.252[/COLOR][/B] (extrapolated BC)
                        With a G7 BC of .252 (think 105 VLD BT) and at a 5600 ft ASL, the following ballistics are possible:

                        Code:
                        Range 	Drop	Wind.	Veloc. Energy 
                        (yards)	(in)	(in)	(fps)	(ft-lbs)
                          0	-2.5	0.0	2706	1853
                          100	0.0	0.0	2527	1616
                          200	-3.0	1.0	2354	1402
                          300	-12.2	3.0	2188	1212
                          400	-28.7	6.2	2030	1043
                          500	-53.7	10.7	1877	892
                          600	-88.5	16.8	1731	758
                          700	-135.0	24.5	1589	639
                          800	-195.3	34.3	1453	534
                          900	-272.1	46.3	1322	443
                          1000	-368.9	61.0	1199	364
                        With all that in mind, I believe a 115 grain version of this bullet has the potential to be pretty potent at some serious distances.

                        Thanks for the chance to evaluate, sneaky.
                        If it's true that we are here to help others, then what exactly are the others here for?

                        Comment

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