Lightweight Hunting Bullets

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  • Lightweight Hunting Bullets

    Our discussion about stronger bolt material for high pressure loads?? led us to the idea that a lighter hunting bullet might satisfy some folks' interest for speed.

    We found there is a fair bit of interest in a premium bullet weighing between 100 and 110 grains. That bullet would have an interesting range and indeed exhibit higher muzzle velocities than the 120 - 130 grain bullets most often found in factory loads. There was also some discussion about even lighter bullets.

    This thread is started to continue that discussion as a topic distinct from the OP's question about higher pressures and the structural changes needed to support them.
    Last edited by Guest; 03-02-2014, 04:53 AM.

  • #2
    As an opening gambit for the discussion, we can postulate converting the 95 grain VMax from a lead-core bullet to an all-copper bullet. When we do that, the new bullet would weigh about 80 grains. Referring to the chart on the Ideal Bullet Weight page, we see that a lead-free expanding bullet weighing 80 grains is within the range of weights recommended for deer and other game animals weighing as much as 330 pounds.

    Weight scaling from the 95 gr VMax suggests that the bullet would have a ballistic coefficient of about .305 and a muzzle velocity on the order of 3025 fps in an 18" barrel. Trajectory for a rifle with 2.4" sight height and zeroed 1.5" high at 100 yards:
    • Range to 5" low = 290 yards
    • 10 mph wind drift at 290 yards " 3"


    These numbers tell us that a hunter with this rifle and load can aim at the center of the vital zone and be reasonably confident of getting the bullet into the vital zone on most days out to almost 300 yards.

    The bullet will slow to the 2,000 ft/sec normally seen as the threshold for reliable expansion at a range of 360 yards. At that range, a spine high hold (13.5" above the heart) will center the bullet in the vital zone. A 10 mph crosswind will move the bullet about 3.9" left or right. This means that the correction needed is moving the crosshair up a bit for all shots within the operating range of the bullet.
    Last edited by Guest; 03-02-2014, 04:54 AM.

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    • Drifter
      Chieftain
      • Mar 2011
      • 1662

      #3
      Doesn't seem to be a significant advantage versus a 223 using a 75gr Scirocco II or 70gr GMX at ~2850 fps from an 18" barrel.

      Plug in the numbers for the 6.5mm 108gr Scenar at 2650 as a theoretical Nosler ABLR with 1300-fps expansion threshold, and and there would likely be more widespread support for a new offering.

      I understand the terminal effects of higher impact velocities in hunting applications, but if you lose significant BC with bullets that are excessively light (and / or with all-copper construction), the long-range appeal of any 6.5mm cartridge is lost. High MV means little if that velocity is shed quickly.

      The gapping loophole in 6.5mm hunting bullets is between 100 and 120 grains, a lead-core segment that would be ideally suited to the case capacity of the Grendel.



      As an all-copper alternative for those that desire it (or are required to use it), perhaps Barnes could redesign the 6.5mm 100gr TTSX to have a 1600-fps expansion threshold like they did with the 6.8mm 95gr TTSX.
      Drifter

      Comment


      • #4
        Originally posted by Drifter View Post
        Doesn't seem to be a significant advantage versus a 223 using a 75gr Scirocco II or 70gr GMX at ~2850 fps from an 18" barrel.
        You stole my next post! Actually, if you look at the Ideal bullet weight chart, you will find the 75 gr Scirocco II, being a bonded bullet, is about right for reliable harvesting of deer weighing as much as 130 lb. The 70 gr TTSX is good for larger animals since it is a lead-free hunting bullet. Neither, however, would be recommended for the 330lb big ones.

        The 2900 ft/sec (24" Bbl?) muzzle velocity for the ASYM offering at Midway, however, means that this bullet would have about 50 yards less reach and a 20 yard shorter point blank range than our hypothetical 80 gr bullet in an 18" Grendel.

        So, we can get bigger game at longer ranges with this hypothetical very lightweight Grendel bullet.

        The point is the Grendel would have a factory offering with a 3000+ ft/sec muzzle velocity and it also would do very well for at least 90% of the hunters.

        We should not ask this bullet to be hugely better than either the .223 or the .243 but that it is at least as capable as the .243 Win and slightly better than the .223 Win. This bullet does that. The muzzle velocity would attract the velocity hungry folks to a cartridge that will naturally take them to the heavier bullets as they understand what the cartridge will do.

        Originally posted by Drifter View Post
        Plug in the numbers for the 6.5mm 108gr Scenar at 2650 as a theoretical Nosler ABLR with 1300-fps expansion threshold, and and there would likely be more widespread support for a new offering.
        You are right, a 108 gr Scenar could represent a reprsentative for an ABLR-class bullet for this exploration.

        FWIW, replacing the lead in a 123 gr SST with copper would give us a 103 gr bullet that has a BC of about .427 and an estimated muzzle velocity 2675 fps in an 18" barrel. The preliminary calculations I ran with this one suggest we have the same pattern as with the heavier bullets. It will really shine out past 400 yards, especially if it is produced with a threshold expansion lower velocity. The 80 gr lead-free, however will likely do as well within 350 yards and covers the major North American hunting animals very well.

        Part of the reason I listed the sight height, barrel length, and wind conditions to to give a common set of conditions for all of us to do these alternative 'what if' calculations. BTW I used the default weather settings for the JBM ballistics calculator.
        Last edited by Guest; 03-02-2014, 01:23 PM.

        Comment

        • bluebird
          Bloodstained
          • Oct 2013
          • 72

          #5
          Interesting

          Comment

          • Michael
            Warrior
            • Jan 2012
            • 353

            #6
            Wouldn't the 100gr Sierra Game King or 110 gr Barnes TTSX be better than the Lapua Scenar 108? We are talking hunting...maybe I don't understand what you are going for, but my impression of the Lapua Scenar was they did not have very good expansion in game, while the other two are advertised as game bullets. From what I remember, the Barnes has a better BC than Sierra, but I could be wrong.

            I ask because I am going to be playing with the Barnes TTSX and Game King later this year...trying some different powders and see what they will do.
            I have never made but one prayer to God, a very short one: 'O Lord, make my enemies ridiculous.' And God granted it.
            - Voltaire

            Comment


            • #7
              Your are right, the Scenar is not considered a hunting bullet. Drifter is referring to a hypothetical bonded hunting bullet that has the same shape as the 108 gr Scenar. That shape with a bonded construction would make for a rather interesting hunting bullet.

              Comment

              • BjornF16
                Chieftain
                • Jun 2011
                • 1825

                #8
                Originally posted by JASmith View Post
                Your are right, the Scenar is not considered a hunting bullet. Drifter is referring to a hypothetical bonded hunting bullet that has the same shape as the 108 gr Scenar. That shape with a bonded construction would make for a rather interesting hunting bullet.
                This is the route I'd like to see it go...
                LIFE member: NRA, TSRA, SAF, GOA
                Defend the Constitution and our 2A Rights!

                Comment

                • Michael
                  Warrior
                  • Jan 2012
                  • 353

                  #9
                  Originally posted by JASmith View Post
                  Your are right, the Scenar is not considered a hunting bullet. Drifter is referring to a hypothetical bonded hunting bullet that has the same shape as the 108 gr Scenar. That shape with a bonded construction would make for a rather interesting hunting bullet.
                  OK...now I understand. What would be the chances of getting the hypothetical to reality? Lapua definitely has the edge with BC. Pulled below BCs from manufactures websites.

                  Sierra 100gr Varmiter BC .259 above 2300fps (yeah, I misnamed it in the first post)
                  Lapua 108 BC .424
                  Barnes TTSX BC .359
                  I have never made but one prayer to God, a very short one: 'O Lord, make my enemies ridiculous.' And God granted it.
                  - Voltaire

                  Comment


                  • #10
                    100 grn TTSX, Lapua brass, CCI 450 primers, and TAC (if you can find it,) is golden.

                    Comment

                    • Drifter
                      Chieftain
                      • Mar 2011
                      • 1662

                      #11
                      It's no secret that 6.5mm cartridges have been somewhat of a late arrival in terms of US popularity. Now that domestic shooters are learning the attributes of the bore size (high BC, and consequently high retained velocity and downrange energy), I don't think that a new low- or mediocre-BC high-MV bullet will do much to change a cartridge's general application or public perception. The saying "It is what it is" comes to mind. So rather than trying to change the application and / or perception of the Grendel cartridge, just make it even better at what it's already good at. The 123gr SST is a good example of this approach. On the first day of its introduction, it was arguably the best medium-game hunting bullet available for the Grendel. A hypothetical 108gr Nosler ABLR (or something similar) would likely supplant it on its own first day, and become a main attraction rather than merely a side show.


                      JA- Would any of the Cutting Edge bullets fill the applications you wish to cover? I've inadvertently stubbled upon some online reviews that seemed favorable, but I have little knowledge of 'em and no firsthand experience.

                      Link: http://site.cuttingedgebullets.com/pages/welcome2
                      Drifter

                      Comment


                      • #12
                        First is all this necessary? Will the 108 work as a hunting bullet as is? The 123 works, it's the same jacket with more lead in the nose

                        Originally posted by dennisinaz
                        Loaded 108 Scenars in my 260AI at about 3275. Worked pretty good on pigs. Need to shoot something bigger with them and see how they hold up. Got an exit.




                        If they don't prove reliable, on a new bullet to get the length you'll need an empty nose like the Scenar, a lightweight core, or a long poly nose.

                        Sneaky, see the jacket width in the middle? If you reduced all of the copper in the BT of the ABLR down to that mid-jacket width how much would it weigh?

                        I understand shortening the bullet will reduce the BC, just thinking about this from another direction.
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                        Last edited by Guest; 03-02-2014, 09:14 PM.

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                        • #13
                          Originally posted by Drifter View Post
                          ...Would any of the Cutting Edge bullets fill the applications you wish to cover? I've inadvertently stubbled upon some online reviews that seemed favorable, but I have little knowledge of 'em and no firsthand experience.

                          Link: http://site.cuttingedgebullets.com/pages/welcome2
                          The 110 grain Copper Raptor listed on their site might actually fill the 100 - 120 gr gap and do it with an interesting bullet.

                          That being noted, however, we still need to think about what might bring more new people into the Horde. Just consider, someone looking at the Grendel and accustomed to the .223 is likely to wonder about muzzle velocities.

                          Offering a good lightweight 80 grain all copper hunting bullet like postulated above could gain a point blank range about 300 yards with bullets more capable than standard .243 Winchester bullets. That bullet would be as flat shooting over 300 yards as the .243 Winchester is with factory 100 grain PowerPoint bullets out of a 6" longer barrel.

                          That might raise some attention if offered in factory ammunition.

                          Comment

                          • BluntForceTrauma
                            Administrator
                            • Feb 2011
                            • 3897

                            #14
                            Originally posted by Drifter View Post
                            A hypothetical 108gr Nosler ABLR (or something similar) would likely supplant it on its own first day
                            That would be a gorgeous bullet. Guys who like 6.5s already like that weight and it would also sell to the 260 Rems, etc., and it would perform as advertised.

                            As I mentioned, my main reason for recommending 100 grains was to market it to the muzzle velocity crazed masses. And I do think it'd perform quite well at 100 grains, witness both the Barnes 6.5 100 TTSX and the 6.8 95 TTSX. So aside from performance, all we have left is perception, which is reality to some.

                            So Drifter, since you might have a good feel for both the 6.5 and the 6.8 markets, how do you feel the 65G is best marketed to the uncommitted who are weighing both cartridges? Another way of saying this is which hypothetical 65G loading at what velocity would attract the most positive attention from the American hunting crowd?

                            John
                            :: 6.5 GRENDEL Deer and Targets :: 6mmARC Targets and Varmints and Deer :: 22 ARC Varmints and Targets

                            :: I Drank the Water :: Revelation 21:6 ::

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                            • #15
                              We have 6.8's loaded with Grendel-weight pills and Grendel powders, and now we want 6.8-weight pills loaded with 6.8 powders...

                              It will be anarchy!

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