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Old November 14, 2014, 10:39 AM   #1
Andrew Wiggin
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.223 gel test: 69 gr Nosler HPBT





Link to video of test

69 gr Nosler HPBT loaded over 23.4 gr IMR 8208 and fired from 19.5" AR with Surefire FA556AR silencer into calibrated 10% gelatin.

BB: 592.2 fps, 3.3"

Impact velocity: 2,743 fps
Penetration: 13.1"
Retained weight: 26.9 gr
Max expansion: 0.557"
Min expansion: 0.375"
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Old November 14, 2014, 11:44 AM   #2
diggler1833
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Those things are pretty nasty at closer ranges before velocity drops off. That includes the SMK family of HPBT bullets too.
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Old November 15, 2014, 01:22 PM   #3
wnycollector
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Thany you for posting the data and gel test. The OTMs are very effective rounds for HD.
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Old November 15, 2014, 01:28 PM   #4
Andrew Wiggin
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Quote:
Those things are pretty nasty at closer ranges before velocity drops off.
Yeah, I would have done an 11.5" barrel test, too, but I was running out of room in the block.

Quote:
Thany you for posting the data and gel test. The OTMs are very effective rounds for HD.
Thank you for the kind words. I agree, but I'd prefer a little shorter neck length. Still very good performance, I think.
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Old November 23, 2014, 07:40 PM   #5
wnycollector
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[QUOTE]Thank you for the kind words. I agree, but I'd prefer a little shorter neck length. Still very good performance, I think.[QUOTE]
I agree, a shorter neck would be preferable. That's why my AR is loaded with Prvi 75gr OTM. It has a 0.8" ballistic neck.
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Old November 23, 2014, 08:14 PM   #6
Andrew Wiggin
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Same here.
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Old December 7, 2014, 04:45 PM   #7
edward hogan
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"Shorter neck"???

I load hornady 75gr bthp and Nosler 69 & 77gr bthp comp bullets as my only .223rem ammunition.. The bullets are super tough, do not fragment even on impact with rocks. They bend like pretzels, but hang together. Lots of hydrostatic shock and even better, Mucho penetration and trajectory advantage; sectional density and ballistic coefficiency.

Load them to magazine length in an AR and you are set. Can load them longer in a bolt rifle. Maybe get more velocity from the bolt rifle w/bullet seated further enabling more powder, but not a real concern for me.

Probably increased danger from ricochets with the bthp heavy jacketed bullets, so not a varminting round with any nearby property or persons. Just maybe your precision AR in .223 could be your best prairiedog gun at moderate ranges like 500yds??? Takes a while to heat up a match barrel and you got eyes on the entire field for 4 or 5 quick shots before the 'dogs wise-up... Out in the middle of nowhere, why not load those heavy match bullets? They aren't really any heavier than commonly selected 6mm lightweights.
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Old December 7, 2014, 05:23 PM   #8
Andrew Wiggin
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"Neck" is the distance from the entry in gel to where bullet upset begins.
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Old December 7, 2014, 05:52 PM   #9
edward hogan
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Thanks, Andrew, for the clarification.

I'm gonna bet you there is NO bullet upset from a 69gr match bullet. Match bullets, at least the commercially produced jobs, all have heavier jackets than hunting or varmint bullets in the weight class discussed here.

There is no real "hollow-point" in a bthp match bullet, just the petals that close the jacket around the bullet core. A true hollowpoint is designed for impact controlled deformation. BTHP is just the means for the match bullet to place its weight where it is ballistically most advantageous; in the back, ahead of the boattail, on the ogive. Thus the point in hollow but totally different design and purpose.

Shoot rocks or concrete with your 69gr match bullet and you will see no "bullet upset". A hollowpoint rifle bullet, typically for highspeed varminting so it fragments and poses minimal ricochet, does not "upset"; it just blows apart. Bullet upset is common in hunting bullets and bullets are designed to upset at different levels of penetration. I think your gelatin test, if using a match 69gr bullet is showing hydrostatic shock, no upset and the hydrostatic wave builds and shows the characteristics of bullet upset.

I used to shoot 90gr Sierra HP from my .270win as a kid and blow-up water filled milk jugs. Only once in a while would recover anything except jacket fragments. A 130gr btsp would do the same trick, but never recovered a bullet. Have recovered hunting and Soft-point bullets fired into snow berms from .243 dia to .375" and they do upset and show R-P core-lokt type bullet upset and jacketing peel-back like the old magazine ad from years back. I had a frisbee full of 168smk and 75gr bthp match recovered from my gravel backdrop range. No match bullet I ever recovered showed upset or breakage. The .224 75gr would bend like pretzels, the .308 168s would simply show the rifling marks and maybe a bit of nose distortion. Lots of rock breakage from impacts, but no bullet upsets or breakage.
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Old December 7, 2014, 06:00 PM   #10
Andrew Wiggin
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No need to speculate. Just watch the video that I linked in the OP. Spoiler: there was a LOT of upset.
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Old December 8, 2014, 02:25 AM   #11
edward hogan
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IF it's a Nosler Competition BTHP 69gr Bullet, it ain't bullet upset that is happening.

Just because the ballistic gellatin shows distortion does not mean the bullet is expanding in diameter or altering shape in any way.

No bulletmaker endorses their BTHP competition/match bullets for hunting. Why? Because they won't expand, upset, or do anything other than punch a bore diameter hole in the animal. Not a big worry if you make a brain or spine shot, or the bullet is a .30, .338 or .375 caliber. Those are pretty big holes in any vital tissue area. The Sierra Techs have told me their Matchkings will out penetrate any other bullet they make and until you get in to .338 diameter gamekings, the matchkings have the thickest jackets of any bullet type they produce. Bullets like the 250gr .338 Gameking have the same thickness of gilding metal because they are more likely to be used on large, dangerous game and the bullet must hold together under those conditions.

Not trying to argue here. but I have never seen a .224 match bthp bullet deform to a larger diameter after striking any material. Maybe it happens at super-high velocity, like a .22-378 would produce? I do recall there were problems with Nosler's J-4 jacketed 155gr BTHP Competition bullets shedding their jackets in flight, but that was a production defect not engineered intentionally.

Most hollowpoint expanding bullets have no barrel contact with the jacket out front where the jacket bonds to the core alloy. The jacket is thinner there and is serrated to facilitate the peel-back mushrooming process once the hollowpoint makes contact with hard surface or fills enough to generate the pressure to begin mushrooming. BTHP are not remotely similar.

I would bet that any bullet recovered in water or some non-destructive media after transiting the gel would show no deformation and could be loaded and fired again.
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Old December 8, 2014, 10:49 AM   #12
Andrew Wiggin
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I don't know how to put this without sounding rude, so please understand that my intention isn't to offend.

You seriously need to just watch the video that is linked in the OP. Many of the suppositions, speculation and "bets" that you have offered are addressed in that minute and twenty second video.

Yes, they are, indeed 69 gr Nosler BTHP bullets. I know this because I loaded them myself. Yes, it did fragment substantially.

Perhaps the confusion arises from my use of the term "upset." It does not exclusively mean "expand". The word "upset" is used to describe any combination of expansion and/or fragmentation.

You are correct that BTHP or OTM bullets are not designed for expansion. They do often fragment in .223 if they impact at a high enough velocity. The velocity needed for fragmentation varies but for most medium to heavy OTMs, it is somewhere around 2,400 fps.
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