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Whats the issue with "core-jacket" separation??

Discussion in 'Caliber Corner' started by glocknbruce, Mar 20, 2010.

  1. glocknbruce

    glocknbruce

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    hey all,

    new guy here.......

    i hear a lot of talk about JHP's that separate from their jacket upon impact, like the standard Golden Sabers...and am just wondering why this is such an issue????

    in tnoutdoors9 video i just watched the lead core went on to penetrate several inches of media, just like any other hollow point usually would.....

    would a JHP be totally useless if it seperated???

    thanks

    Bruce
     
  2. KiloBravo

    KiloBravo NRA Life Member

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    This is just what I think about it...

    Of course any rounds on target are going to inflict damage and even a completely seperated hollowpoint will not be deemed "useless."

    However, the idea behind jacketed HP ammunition is to expand as it enters a target and penetrate deep enough to reach vitals. However, if the bullet goes too far in, then you risk the chance of over-penetration and hitting something you did not intend to shoot behind the initial target.
     

  3. unit1069

    unit1069

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    I assume that's the video I saw a few nights ago. I recall that the core didn't expand much.

    The core isn't useless, but if it doesn't expand properly the defender loses much of the advantage having a JHP round gives. I'm rethinking carrying the Golden Saber in one pistol I have because of the numerous tests showing jacket/core separation.
     
  4. David_Ely

    David_Ely GAP'r

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    It is desirable for the expanded jacket and core to stay together to do maximum damage as it travels thru the body. If the sharp edges of the jacket only penetrate a couple inches and a solid core continues, it won't do as much damage to the internal organs/flesh as an intact expanded jacket and core would do.
     
  5. Brent10mm

    Brent10mm

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    Core-jacket separation is usually something to avoid.

    the exception here is, fragmentation... more specifically high velocity rounds such as .357mag, sig, 10mm... ect. In which the jacket is slowly broken up as it expands and penetrates, something like a directional grenade.

    tnoutdoors9's vid with the golden sabers is an example of something to pass on. I have had them slip as well. golden sabers are generally a good choice in a SD role, but it does happen. GS's are traditional style bullet, in the fact that they use a swagged lead core, lube it up, and push it into the jacket... under high stress and velocity it will slip.

    the better choice would be a bonded bullet, or a newer traditional design... such as the Win ranger T's, or Federal HST's.

    TN9 also has a vid of buffalo bore 124gr gold dot +P+, watch that one... it is a good choice for your G19, and its what I have loaded in it.

    in my G36 45 is win ranger T's, it as well as fed HST's just plain out perform the bonded bullet in this caliber...
     
  6. DEADEYEGUY

    DEADEYEGUY

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    It becomes a big problem first off if you have to shoot through something to get to the bad guy. The barrier will often cause this separation and the bullet will not strike the bad guy. Net the separation often causes the two pieces to not go deep enough. As one guy put it "I'd rather have a nice deep hole ad opposed to a dramatic crater".
     
  7. squirrelsniper

    squirrelsniper

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    Core-jacket separation is typically of the biggest concern when shooting through glass. Glass seems to cause core-jacket fragmentations more than any other material. While this can be an issue, it's not something most civilians need to be overly concerned about.

    Actually, core-jacket separations can be beneficial. Assuming you don't have to shoot through intervening materials such as glass or steel, separation or even complete fragmentation just causes extra wound channels as opposed to a bullet that stays together and does not shed any fragments.

    Just like the current fascination with bonded hunting bullets, I think it's an issue that's been hyped to the maximum:soap:. While it can be an problem, there's much more important things for shooters to be worried aboput.

    Of course it gives everyone something to talk about on forums like this.
     
  8. fredj338

    fredj338

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    Good post. Core/jaclets sep is less of an issue when you don;t have to shoot through hard barriers. The typ jacket of a 230grJHP weighs about 30gr so even if it seps upon entry, you have a soft lead cor weighing 200gr that is still likely expanding & continuing to penetrate. Now you hav likely two separate wound channels which doens't hurt anything. Core spe is more an issue w. lighter bullets that are laready struggling to get good penetration IMO.
     
  9. cyrsequipment

    cyrsequipment Angry

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    I have yet to understand why seperation is an issue for civillian self defense rounds.

    I'm having a difficult time seeing a REALISTIC scenario where the average person is going to be shooting through a window or a car door, or a bit of drywall...:upeyes:

    But then again, some of these idiots think that they can take on the police or military...:rofl:
     
  10. LEAD

    LEAD

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    The theory has a lot to do with the physics of a projectile in flight.

    We can use Fredj338's example to illustrate as I have not the slightest about how much the typical jacket weighs.

    Say you shoot a typical .45acp 230gr Projectile going 850fps. Upon impact of a person or a barrier, the projectile experiences core-jacket separation. Now you still have the same amount of weight in flight, however it is now in the form of one 200 gr lead and a 30 gr jacket.

    These objects are less capable of reaching the same penetration depth as they were as one entity as mass has a lot to do with energy and objects that are in motion tend to stay in motion, an object that has a greater mass is harder to achieve the same change in velocity as an object with less mass. Thats why when you do see examples of core-jacket separation, the small fragments like the jacket typically penetrate shallow, while the core goes deeper. Now looking at the core only, say that the core sheds the jacket before reaching the gooey center. The projectile now has lost about 13% of the mass and has not gained any velocity, therefore assuming the same relative velocity and exspansion with a loss of mass of 13%, penetration would suffer, that is if the core exspands as it is supposed to.

    You'll also notice that the expansion of the core is effected by the absence of the jacket

    In short perfromance suffers as a result of cor-jacket separation
     
  11. fortyofforty

    fortyofforty

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    If you "work" a lot in and around vehicles, you might want to make sure you're using bonded bullets. Shooting through windshield glass and door panels is tough on all bullet designs. However, I agree that for civilians, any traditional, modern hollowpoint should be fine. There are plenty of great choices, like SXT, HST, and GS.
     
  12. DEADEYEGUY

    DEADEYEGUY

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    All I can say is I fired some .45 185gr. +p Golden Saber non bonded rounds into some water saturated phone books and got jacket and core separation. I know the wet phone book thing is not scientific but they didn't go very deep before separation. Didn't inspire confidence. Again not scientific but I shot some Cor Bon 9mm 115gr. rounds through some pine boards. Most fragmented in the first board with particles going into the second. If the bullet goes deep enough then separates it wouldn't be a bad thing. The problem again is depth. Maybe for home defense the lower penetration might be a good thing. Their is a reason the Gold Dot rounds are so popular. And others are now following suit. I'm pretty sure the Winchester 115gr. +P+ round would do a good job on someone if you did your part. The 127 gr. +P+ rounds often in real life run very close to the lighter rounds plus the talons and the better bullet integrity. Again nothing against the 115gr. +P+ rounds. They have been proven to be effective by eberyone that use(s) them. I just like the faster middle weights better.