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Benefits of Ballistic Tips on Big Game Hunting BulletsBig Game Hunting topics that dont fit other categories
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Jul 16, 2013 12:17 pm Post subject: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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This Thread ended up being a bit long but I hope you will find it interesting. I have learned a lot about bullet expansion and had fun doing this series of testing. So let’s begin.
I have been involved in several discussions regarding the benefits of plastic ballistic tips and what degradation would occur if the tips were modified or removed from a bullet. I’ve always believed that the primary benefits of the ballistic tips are improved ballistic coefficient and “sales appeal”. When pulled from the bullet’s body, a ballistic tip is hiding a much larger hollow point/expansion cavity from the wind which obviously does improve the bullet’s ballistic coefficient (BC) compared to the tip not being there. As an example, the 85gr E-Tip has a maximum expansion cavity of 0.130" (almost ½ the bullet’s diameter), the 110gr TTSX is 0.100", and the hollow point opening of 85gr TSX, which doesn’t have a ballistic tip, is less than 0.050".
After seeing how rapidly the monolithic copper bullets are opening up during terminal performance testing and on game I have shot, I have also thought that ballistic tips could be promoting bullet expansion on impact with the animal, forcing the bullet open quicker and to a larger diameter. As an example, I have observed Hornady’s 130gr GMX is fully expanded before it enters an elk’s chest cavity based on the entrance wound on the inside of the rib cage is as large as the exit side.
To test this assumption, I modified some monolithic copper bullets, specifically Nosler’s 85gr E-Tip, Barnes’110gr TTSX, and Hornady’s 130gr GMX. Two modifications were done to the 85gr E-Tips. One with the tip shorten and filed blunt/flat but still protruding some length beyond the bullet’s copper body, and the other with the tip completely removed leaving the gaping expansion cavity. The 110gr TTSX and 130gr GMXhad just their tips removed leaving the large hollow-point exposed. The tips were easy enough to remove on the E-Tips and TTSXs (not so on the Hornady GMXs or any lead-core bullets I have). I place a loaded shell into my single stage loader without a die in it, raised the shell so the tip was just exposed above the top of the press, and then held the tip with a pair of wire cutters as the case was lowered. The tips just popped out exposing the larger than normal expansion cavities. I did have to recheck seating depth and recrimp as some bullets moved. The tip on the GMX had to be drilled out.
The assumption going into this test is, with the ballistic tips removed or modified, expansion would be reduced. Below are the results of the modified bullets pulled from the bullet trap at 100 yards. The 85gr E-Tip and 110gr TTSX were shot from a 6.8mm SPC II. The 130gr GMX was shot from a .270 Win. Note that these are monolithic copper bullets and the results below may not apply to jacketed lead-core bullets.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein
Last edited by slimjim on Wed Aug 07, 2013 7:33 pm; edited 1 time in total |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Jul 16, 2013 12:21 pm Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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These are results. The bullets were shot into the bullet trap I have developed.
www.huntingnut.com/ind...ullet+trap
Nosler 85gr E-Tip – Surprise! Both modifications resulted in more expansion, especial when you figure in the effect of reduce BC on velocity (all impact velocities without the pointed plastic tips are estimates). The bullet with the ballistic tip removed was largest and you can see how the expansion cavity is stretched more. I was also impressed with the reaction of the water jugs on impact. Both modified bullets stop in the phonebook before they reached 1000 pages.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein
Last edited by slimjim on Tue Jul 16, 2013 12:32 pm; edited 1 time in total |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Jul 16, 2013 12:30 pm Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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Based on this testing, there now is another reason you might want to remove ballistic tips other than wanting to use up some of your longer .270 bullets and have them feed through your AR magazine. From a terminal performance perspective in short range situations less than 100 yards, the advantage of removing the ballistic tips can be more expansion and reduced risk of over penetration. I do not recommend or see where it would be worth the effort to remove the tips on the 130gr GMX or 110gr TTSX. However, specific to Nosler’s 85gr E-Tip, with the tip removed it becomes a more effective home defense round (note, leave the seating die depth unchanged so the bullet seats the same giving plenty of magazine clearance). For those that need a lead-free bullet for hunting, the heavier longer 130gr E-Tip could potentially become an option in the six8 assuming it has the same effective expansion cavity design that the 85gr E-Tip has. I need to test the 130gr E-Tip to verify this but predict with the tip removed, it should stabilize in a 1:11 twist as the calculated stability factor improves to 1.26. The 130gr E-Tip would provide deeper penetration when hunting hogs with the six8 and possibly an advantage in areas of dense brush. Besides the advantage of being able to stabilize the longer 130gr copper bullet, there should be less chamber pressure and more powder capacity because the bullet can be seated longer in the six8 case which should also result in a higher muzzle velocity. Just remember to stay at least 0.050” off the lands to avoid pressure spikes.
Note: the bullets with the ballistic tips removed fed from the AR magazine ok but should be cycled through your specific action multiple times to ensure reliable feeding if you choose to do this. I do have my feed ramps modified so they continue down into the upper receiver (see example below) which could be benefiting reliable feeding with these modified bullets.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Jul 16, 2013 12:33 pm Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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Here is another comparison of like bullets with and without ballistic tips shot from a .270 Win. Both these bullets are unmodified. One is a Barnes 130gr TSX hollow-point that is produced without ballistic tips. The other is a new Barnes .277 129gr LRX with a ballistic tip that is advertised to have a lower opening velocity, down from 2100 to 1600 fps. The LRX has the “new” cavity design that is claimed to be similar to the six8s 95gr TTSX (you will see later that they are not quite the same). These tests were conducted at 100, 300, and 500 yards. The LRX showed excellent accuracy at all ranges shot from my Tikka T3 Lite, < 1 moa. I expected the LRX to out expand the legacy TSX and I was not disappointed as you can see from the picture below. The 130gr TSX does well, especially considering the smaller expansion cavity, but the 129gr LRX does better and provided the largest recorded expansion at all 3 ranges of any monolithic .277 bullet I have tested, an impressive 0.611" at 100 yards and still doubling in size at 200 yards.
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_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein
Last edited by slimjim on Wed Aug 07, 2013 7:46 pm; edited 3 times in total |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Jul 16, 2013 12:36 pm Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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To complete the search for knowledge and understanding, below are cross-sections of several 6.8/.277 monolithic bullets. You can see the expansion cavity in the E-tips and GMX are the largest. All the other bullets are pure copper where as these two are 95% copper/5% zinc – the same alloy used in copper jackets for lead-core bullets. An alloy of 95% copper/5% zinc is harder which is likely the reason the E-Tips and GMX need the larger expansion cavities. Here are a couple of interesting aspects to note. The 95gr TTSX, 110gr TTSX, and 129gr LRX all have different size blue ballistic tips and associated expansion cavities. The 95gr TTSX expands at lower velocity because it has the largest expansion cavity of the Barnes bullets. You can see there is less copper structure around the expansion cavity of the 129gr LRX when compared to all the other Barnes bullets. This is likely the reason the LRX is claimed to expand at lower velocity even with its smaller expansion cavity and why it is losing its pedals during expansion. Finally, notice how much smaller the expansion cavities are for the non-tipped TSX bullets yet their expansion is typically as good as or better than the tipped bullets within their designed speed/energy range.
Thus, from the results of this testing where every bullet with its ballistic tip removed expanded more, and the fact that monolithic bullets with ballistic tips require larger expansion cavities to achieve similar expansion to monolithic hunting bullets produced without ballistic tips; it can be concluded that the addition of the ballistic tip does not promote expansion for monolithic hunting bullets. Again, these results may not be applicable to jacketed lead-core rifle bullets that have ballistic tips.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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Ominivision1 Super Member
Joined: Sep 20, 2010 Posts: 2984 Location: Iowa
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Posted: Tue Jul 16, 2013 2:00 pm Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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Excellent research and testing Slim!!
_________________ Regards
Limitations are but boundaries created inside our minds. |
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gelandangan Super Member
Joined: May 07, 2006 Posts: 6396 Location: Sydney Australia
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Posted: Tue Jul 16, 2013 2:36 pm Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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Awesome write out Slim!
Great job.
Thanks!
_________________ A straight line is the shortest distance between two points.
A smile is the shortest distance between two people.
Do - Not try!
gelandangan.weebly.com/ |
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Elvis Super Member
Joined: Jul 27, 2008 Posts: 9239 Location: south island New Zealand
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Posted: Wed Jul 17, 2013 12:27 am Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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great write up indeed .
so are you going to try to create a better hollow pointed copper solid with say a 3mm hole drilled 7- 10mm into it????
_________________ You shot it You pluck it !
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Vince Site Admin
Joined: May 25, 2005 Posts: 15704 Location: Brisbane AUSTRALIA
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shrpshtrjoe Super Red Neck Member
Joined: Jan 26, 2005 Posts: 2965 Location: Maryland
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Posted: Wed Jul 17, 2013 2:57 am Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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There's a lot of good info here slim thanks for sharing it..
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Wed Jul 17, 2013 4:23 am Post subject: Re: Benefits of Ballistic Tips on Big Game Hunting Bullets |
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Thanks guys. This was a fun project.
Elvis wrote: |
so are you going to try to create a better hollow pointed copper solid with say a 3mm hole drilled 7- 10mm into it???? |
Elvis, that certainly would have the potential to work. However, that is a lot of work. I don't think you can beat Barnes and how they design their copper HPs plus all the copper ballistic tip bullets work consistently well.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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