Are core/jacket separations common in 7mm 120 NosBT?

[patrick_sween]

Just out of curiosity, I shot one into some gallon milkjugs of water, at in impact velocity of about 2100 fps.  The core and jacket separated at the second jug (after about 9" penetration) and the jacket made it into the 4th jug.  The core departed for parts unknown.  Is this common for this bullet?  Water's not that tough a medium, so it makes me wonder how penetration would be on harder stuff (read: critters).  I know guys have had good luck on deer with these, and I won't argue with results, but it seems questionable to me to have them come apart that easily.  Anyone got any better info?

Patrick

[jhalcott]

I always thought water was a tough medium. A 44 mag shot straight down into a 4' swimming pool wont penetrate the bottom. BUT, I ve shot 6mm 90 grainers into milk jugs over 500 yards away and they went thru several jugs.Usually stopping in the fourth jug after exploding the first 2.
 I've tried soap bottles at different angles and get results depending on the amount of water the bullet must pass thru .How many jugs did the core penetrate before it went into the unknown?
  Was your test repeated to make sure it was not a fluke? The ballistic tip is not as tough as the partition but I'd think it would be tougher than that.

[patrick_sween]

There were two exit holes in the third jug and only the jacket entrance into the 4th, so I don't know how much oomph the core had left by then.  It veered off at a pretty steep angle, since there was only one ragged entrance in the third jug and the two exits were a good two inches apart.  I had all the jugs lined up in kissing contact and the first three were center punched, so I know my alignment was on.

I don't know whether to call water a hard or soft medium.  It's certainly softer than bone, but muscle and guts are mostly water.  I may shoot a few into saturated newspaper to see how they do then.  In any case, most of my "testing" is done purely for entertainment, so I don't know if I worry about the results too much. I've always been interested in recovered bullets and trying to figure out what they accomplished.  

I ran out of jugs shooting my .357 into them so I didn't get a chance to repeat the test.  Just for info, a 140 gn. XTP in the .357 went consistently through three jugs, and just dented the 4th.  I got some nice expansion and pretty mushrooms at an impact of about 1250 fps.  Whether that's useful or not, I couldn't tell you, but those jugs make such fun targets for open sighted pistols!

Patrick

[Duffy]

Patrick,
I have tried many types of medium, water, soaked papers, wood, pvc ect and have of yet to have a BT NOT shed or completely come apart. Even the partitions will lose the front portion of the core but at least the rear is still pushing and the jacket stays intact. Of the deer I have shot with a BT  in 270 & 7-08 cal all of them turned to fragments but it only took one shot. I wish they made a bonded core in a lighter variety for the 7mm. Am going to try the Hornadys and see if they fair better.
Water is a pretty stiff medium at first impact, it's just that it dispurses quickly unlike muscle and or wet news print.

As a example of the force excerted I took a 2 1/2 gal plastic jug filled with water and set it on a piece of 1/2" chip board on top of a 30 gal drum with the top cut out.  Hit the jug with a 7mm Mag at 100 yards. It of course split the jug but it also punched a hole through the board where the jug was sitting.

[Blackhawk44]

From the results that I have seen in game, yes, core separations with Ballistic Tips seem to be rather common.  The same seems to go somewhat of almost any boattail, but the majority of BT kills indicates an even higher likelyhood.   Pretty good varmint bullet, I do not consider them a reliable game bullet.

[Hawkeye]

I still use them but I have gone to the Hornady 139grn SST in my 7-30 Waters Contenders. I had a couple of the Ballistic Tips come apart but took the deer down, on the spot. Had two or three exit wounds on one shot. The BT's did hit bone. The SST is really built for rifle velocities from talking with Hornady but they have taken three deer and none have gone over 15 yds after beeing hit and all seem to have stayed together due to only one nice exit wound. The SST is supposed to have a interlock ring on the jacket and core to hold it together.

Mike

[rickyp]

In place of the water why not try getting some duct seal. it is a gray clay type of stuff sold at most hardware stores. It is very ply able and fairly close to what flesh  with out the bones. after you shoot up just remove all the Pisces of bullet and remold it back into a big block. You will need about 20 lbs of the stuff to work and more will be better.

[Jim Stacy]

I have a friend that shoots meat to test bullets . He shot some whole chickens , not live just  whole cleaned with a piece of cardboard  behind it as a witness print for expansion. He shot a rack of ribs with hamburger meat inside the ribs all in a plastic bag and all taped down with a witness piece of cardboard behind it to check expansion . He quit shooting the chickens at the range for the abuse and razing he got for it. JD Jone used to test his stuff through antifreeze jugs full of water with a witness board behind it. All of the above will give you some indication on bullet performance but none of them just like real game, although a good chicken shooting is hard to beat . ;-) Jim

[PaulS]

I use a wooden frame that holds gallon size "zip-lock" bags in a horizontal column 98 inches long (or deep). I use salt water in the bags and get consistant results. I test for expansion and penetration and with this apparatus I measure penetration to the nearest inch and the expansion results are comparable to expansion in soft tissue of live game - hitting bones, of course, changes everything.

It is a kind of "Fackler box" named after its inventor.

There is a direct correlation between the penetration in this device and the penetration in living animal soft tissue.


PaulS

[Jim Stacy]

Paul we have done a little of the water filled bag testing, never thought about using salt water solution to increase density --- good job! I know when you whack the bags with a 44 cast hp it is pretty enertaining. I guess you could also add some gelatin to better memic tissue , damn good idea I wish had thought of that --I'll have to try it all again.

[Elwood]

Dear Friends,
Barnes 7mm 120 grain X bullets. No separation, High velocity, expansion down to 1000 fps.
Elwood

[Lone Star]

Much ado about nothing IMO.  I've shot dozens of deer with BTips in handguns, and seen dozens of others shot, and every one has resulted in a quickly-dead deer.  The only bullets I've recovered have been from long-range shots over 200 yards, and both of those gave stem-to-stern penetration and a dead deer.

What are people thinking when they "test" bullets in water jugs, clay, paper, meat....when bullets almost never see such solid medium in an animal.  For lung shots the bullet penetrates an inch of hide and rib tissue, then passes through the lungs which are mostly air, then passes through the ribs/hide and out.  Almost any decent shot into a deer does not require the bullet to pass through more than a few inches of solid material.  If you are shooting deer through the paunch, then the BTip isn't the bullet you should be using - try a Speer HotCor or a Partition or an X-bullet...

We as shooters are brain-washed by gunwriters and bullet makers into believing that a bullet must retain all its mass after a hit, and that a core seperation means the bullet somehow won't kill an animal.  In reality nothing is further from the truth....as long as the deer is harvested cleanly, does it really matter what the bullet's condition is?  Use whatever you feel comfortable with of course, but to condemn a bullet because it comes apart in a foot of solid water is like saying that a .300RUM is needed to kill deer because a .308 Winchester isn't powerful enough for bison.

Elwood, I must disagree with the comment about X-bullet expansion- although I use x-bullets in many of my rifles and like them.  The 7mm 120 X-bullet exibits no useful expansion at 1000 fps.   Barnes says that expansion begins at closer to 1600 fps - and even then the expansion is really just a deformation of the nose rather than a decent diameter mushroom.  The muzzleloader and handgun-specific bullets will expand well at 1000 fps due to the very large hollowpoint and bullet temper.