Home Forums Hunting & Shooting Hunting Rifles Cup and Core Jacket Integrity/Separation

I decided to start this thread after going through the "Bullet Failure" thread. I just wanted to take a moment to show the difference between a bullet that loses it's core or one that holds together. What I have found is that the difference between the two can be very little.

This bullet is a 65 SGK fired out of a 223 Rem just south of 3000fps. The impact was at 50 yards and the target media was water jugs. I fired a total of 6 shots into jugs. The first three shots were fired into jugs with a 3/4" plank of red oak plywood taped to the front of the first jug. The last three were without. Interestingly, bullet performance was indestinguishable between the jugs with the plywood and the jugs without. There was no discernible expansion occuring in the plywood. The bullets penetrated the same number of jugs as well.

So here is one of the bullets;

as you can see, the expansion is dramatic and the core and jacket are intact. This is how I recovered the bullet from the gallon jugs.
Another picture


While handling the bullet, the core promptly fell off.


As you can see, there is very little left of the core. The weight of the bullet now is 35 grains, so it lost nearly half it's weight.

As one person said in the failure thread, you don't see ads with just the jacket of the bullet and no core. He is right. But, look how easily a bullet which retained it's core can lose it's integrity.

This is why you match the bullet to the game and choose your shots accordingly. Even though this 65 SGK is not the toughest bullet out there, I think it will handle lung shots on does without a hitch.

I've seen strange things with bonded bullets and cup and core bullets. It just goes to show you that no single bullet strike is the same. Improve your odds using the appropriate bullet for the task and placing it in the right spot.

That's why the old timers used to use "heavy for caliber" bullets especially for the bigger game animals....Here's a 250 gr. sierra gameking that seperated after passing thru a bulls colar bone and busting its vertebrae. The core went out the far side (creating an exit wound) but the jacket was left up against the far side hide...This is from a 338 win mag at a modest velocity (alright it was slow ) of 2600 fps. It did put the bull down fast and did penetrate bone so what is failure and what isn't? The bull didn't even take a step (drt) so it was good enough for me:








I'll be using my 9.3x62 mm mauser this year so we'll see if the 286 gr. nosler partition is way overkill.....We know it will penetrate and hold together.....probably about 2 elks worth.....

I think the old heads were smart to use a heavier bullet for the caliber when more penetration was needed. I think the important thing to look at is achieving a velocity with a given bullet that will allow it to perform as desired. A lot of times that means loading up on bullet weight. When you drop the trivial desire for blazing fast velocity or shooting a deer at 700 yards, I think you can find that cup and core bullets of some sort or another will do just fine.

Never had a Barnes X, XLC, TSX or TTSX lose its 'core' ...

Sure, I could use a heavy for caliber bullet like the old timers, and I could drive up to the mountains in a model A pickup truck too. I CHOOSE however to use better equipment because my time in the hills is precious.

The desire for speed is not trivial, it is what has driven most of the cartridge development ofr the past 150 years, and rightly so. Flatter trajectories, lessened recoil and increased hydraulic effets of the bullet strike are all winners in my book.

I pick bullets that will penetrate enough to give me two holes everytime and then try to achieve a 2700fps STRIKING or impact speed for as far out there as I can get it as this is the threshold where even soft tissue can often become secondary missiles and hydraulic pressure upon the CNS often overcome all of the swithchwork in an animal and turn its lights to OFF, and right now. DRT, Bangflop, whatever you want to call it is my goal. Since switching to relatively light for caliber Barnes TTSX bullets lit by 70-90 grains of various propellants, depending upon caliber, I achieve these DRT/Bangflop events far more often than I used to and easily in the majority of cases.

Cup and core bullets on my loading bench are all varmint bullets or pistol bullets where they are still benchmark performers. OK, I have a small confession to make, just remebered that I DO have some cup and cores for my 348WCF, 250gr Barnes Originals, and hope to do some old timey hunting with them someday. But for serious work, there is much better out there and many great reasons to use them.

"Never had a Barnes X, XLC, TSX or TTSX lose its 'core' ..."

Not to be argumentative and I don't use mono's because I have never had trouble collecting deer with c&c's so my experience with them is nil, but for those of you that use mono's I pose a question. I read about their occasional penchant for failing to expand. So how many of you mono proponents have experienced this and wouldn't this count as a failure too? I sort of suspect this might be more common than expected but due to pass thru's it might not be recognized.

This weekend I shot two nilgai cows with my 375 Ruger using 300gr Sierra Game Kings loaded to about 2450 fps muzzle velocity. The first one hit right behind the shoulder, just like you'd shoot a whitetail. It fully penetrated with no notable performance issues other than a dead 350 lb cow. My second kill was a spinal shot, which completely severed the spine and caused core/jacket separation. I recovered the jacket, which appears to be very thick, and a small piece of the core. She of course dropped. Another gentleman in our group shot a cow square in the chest with a 150gr Winchester Ballistic Tip from a 30-06. It too separated, but the cow dropped without taking a step.

I know that premium bullets do have their place, particularly in allowing some cartridges to step up in killing capability. However, I do not believe that core/jacket separation is the difference in a clean kill or a lost animal. First, the only way anyone ever knows the core/jacket separated is by recovering the bullet from the animal (i.e., successful hunt). Second, in my experience, a piece of the core always exits and other pieces are found as shrapnel in the vital organs. Complete penetration with interior shrapnel. That's a dead animal folks, and until the day comes that I find an animal after a brutal extended tracking period in which it appears that core separation was the cause, I ain't gonna worry about it.

Never seen an X not expand, that said they do like speed.

Had an interesting conversation with a guy recently that had killed 200+ critters in Africa with Barnes bullets, he says he just laughs at all the 'they don't expand' blubber.

I like to load one bullet for tags and prefer a bullet that works when everything is wrong, not when everything is right.

If I spent the majority of my life hunting in a box, overlooking a feeder for deer I could likely 'wait' for that double lung shot, but then again I don't see myself ever moving away from busting shoulders.

I also spent my entire adult life moving every few years so I figured having one premium bullet load and one for playing only made sense.

Sort of wedded to the one gun/one bullet theory myself, but don't fiddle much with a hunting tool. Work up the load and move on. Other guns serve for amusement and fiddling around.

Bullets come in three basic forms. Lead, C'nC and premium so far as I'm concerned. Two of them won't shed a jacket. All of them have velocity ranges where they do their best work. My personal opinion is that for other than varmint work speeds outside the 2000-2700 fps range is not the place that serves to best advantage with C'nC bullets.

Exceptions? Sure, but I've not the time to test every little nuance of bullet performance, nor am I inclined to do so. Can you cover that with monometal bullets? Pretty much. Can you harden up some lead and do it with cast bullets? If you want, yes. Can you kill chitt(ok) dead with C'nC bullets? You betcha.

They all have baggage as well as advantage. Do what makes you happy, aim small and carry on.

bangeye-

My first experience with mono bullets was with the 7mm 160g Barnes XLC in my 7mm RM, launched at 3020fps. Results varied on coyotes, from very impressive damage with a spine hit to no entrance or exit wound that I could find at 100 yards (read �still good velocity�). Both dropped like a rock. In preparation for an elk hunt I used the XLCs on antelope and that was the end of my experimentation with them. Two through the lungs failed to kill it, although they did cause it to ay down as if sunning itself. Some 20-30 minutes later, after I had circled around for a closer shot, it struggled to its feet and started to walk away. A third through the heart finished it. After that experience I couldn�t bring myself to use TSX�s, either.

When the MRX and TTSX came out I gave them a try. So far results have been very good with most animals (deer and antelope, no elk yet) dropping straight down. So far we have not recovered any as all have exited regardless of angle, including a 180g MRX that penetrated a mule deer from front to back.

Failure to expand? So far we haven�t seen any sign of that with the TTSX or MRX. The tips seem to be doing what they are intended to do � promote very rapid expansion.

As to the high percentage of pass-thrus (100% for us so far), I suspect this is because the monos have less frontal area after expansion than typical C&C bullets.

Safariman, I know I have seen you mention the 2700+ fps impact velocity thing before. While I will not criticize your way of doiing things, I just want to know, what load combinations are you using that allow you to whack animals with that kind of velocity at distance? It just seems like you would be using magnum, long range type cartridges for relatively close range work. Not trying to be a jerk here, as I honestly believe in to each his own. Just curious as I have not looked at things the same way you have. Just trying to see the light.

I know some people will criticize me for the way I do things... My hunting experience basically peaks with deer and hogs. I would love to do more someday, but I just have to take life as it comes and an elk hunt hasn't been in the cards yet. Having said that, I do kill deer out of blinds, but I also kill just as many on foot. The ability to load and practice with a cartridge at a cost that keeps costs down is a matter of practicality for me. Between school, a mortgage payment, 3 and half dollar gas and a metabolism that forces me to eat anything that isn't tied down, I am fortunate enough to be able to fund the hobbies that I do have. I guess this just gos to show that individual reasoning for choosing a bullet is more important than hypothetical bullet performance.

Good post! Two thumbs up....some people travel,not just in the course of daily life and where they live, but to hunt as well.And don't hunt predictable,static,and familiar country every year.Seasons may take in more than one type of animal in unfamiliar country.

My first western hunt was in the Missour River breaks; I thought all western terrain looked like that;until I got to SW Colorado...then other places.

The post above by Jeffrey regarding ideal velocity is food for thought.....I wonder...how do we know exactly what that is going to be on any given hunt? It changes dramatically with distance.So does what may be expected of a bullet.

In the end, a premium for hunting and a "practice" bullet with the same POI and load proved more than satisfactory.This has never failed to work if I did my part.

That is all true, Sir. When I was stationed in California I hunted with a 7mm-08 and I didn't reload out there because I lived in the barracks. I did eventually get a reloading bench set up at a buddy's house, and by that time I was using a different rifle, but while hunting those SoCal mule deer that first year, I was forced to pay 40 dollars for a box of Winchester ballistics silver tips because ammo was in short supply for some reason at the time.

The way I try to attack the velocity issue is by increasing bullet weight in a given cartridge until I am at a good starting velocity. Judging by the bullet pictured in my OP, I think I am going to try the 70 grain Speer SP now. While I think the 65 SGK will work fine, I think a little more weight and a smidge less velocity might help a bullet hold together a little better. Of course, I could use a monometal, but that just isn't near as much fun.

Thanks Jeff.I see where you are coming from.

Actually, we could take a clue from the 'oldtimers' and know our bullets a bit better when applying them these days I think. In that respect they had it easier perhaps since they had fewer things to consider - fewer bullet choices- so going 'long' for deeper penetration was one of the few rules they needed to know. But we still need to 'know' our bullets. Many or most bullet failures still involve mistakes in selection or application IMO.

And two holes are nice but you best not count on them with even the monos:





(Though, to be fair, this one made three holes; two through the first animal, and on in the second - and it was only a 100 grain 7mm!)







...and speed; better have some if your bullet needs it.

There is still a standard against which others are measured, and it ain't a Johnny-come-lately!

Is that a TSX or a MatchKing??? lol, jk. That one was below the belt.

Jeffrey
I recently found a good article comparing some 22 centerfire bullets for deer.

It was on a UK shooting sports website and was entitled "22 Caliber Bullets for Deer Stalking". It used the bullet test tube and was a neat study. The sierra 65 GK faired quite well. I was interested because my newest fast twist 223 does not shoot my beloved 64 pp very well, but it does shoot the 65 GK very well (5 shots under 1 inch at 100 meters pretty consistently)

Thanks Colin! I have loved Sierras as long as I have been handloading. I am making it my business this fall to find a good cup and core deer bullet for my 223.

Man, what do we have now, three months to deer season? Can't wait...

I've killed a bunch deer over the years with the old stand-by Hornady 55gr SP out of a .22-250.

My godfather is the man who took me on my first deer hunt when I was 11. He always used a 22-250. He only took head and neck shots though. Not sure what bullet he shot.