Another thread questioned the hornady interlock btsp vs the nosler partition. I think this is a more even playing field.

Given the same caliber and weight, which bullet will mushroom and hold together better? I have used the Hornady's, never tried the Speer hot core flat point (yet).

IME the Hornady is a little bit tougher. Unless your comparing the Interloc to the Grand Slam, then it goes the other way.

In choosing between the two, I'd pick the one that shot best in my rifle. I really doubt that Hornady's "Interlock Feature" or Speer's "Hot Cor Process" has a definite edge over the other in the field. Start either of the two at a reasonable muzzle velocity of 2,800 fps and both will bring home the venison if the shooter does his/her part.

FWIW:

1-all the reports I have seen/heard have them about equal/

2-My experince on wild hogs has been excellent with the 150 grain grand slam from a 308. Really a nice bullet for the tougher hides and bones of the hog.

BMT

I've killed mule deer, whitetails, Sitka blacktails, elk, caribou and pronghorns with Speer Grand Slams, Hot Cores and boattails. I've killed mule deer, pronghorns and caribou with Hornady Interlocks. Muzzle velocities ranged from 2400 fps to 3000 fps; calibers ranged from .257 to .358.

In order of "toughness", I would rank them this way:

Speer Grand Slam
Hornady Interlock
Speer Hot Core
Speer Boattail

I would happily shoot any deer on earth with any of them out of any of my rifles from .277 caliber on up. I did find that the 250 gr Grand Slams at 2400-2500 fps out of my Whelen did not expand well on moderate sized mule deer bucks. I also found that with a .358" hole punched all the way through the deer, and everything in between the entry and exit holes broken into fragments, that apparent lack of expansion didn't matter much...

I have found even the none-Hot-Cor BTSP to be about as good, if not better, than the flat based Hot-Cor. This one broke both shoulders of a 130 pound animal.



Another caribou bullet, this one a 6mm RN 100 grainer was taken from a cow shot at 100-200 yards with a 6mm.



Of course, big bones can also play havoc as seen in the following:



The Hornady 250 35 caliber, even at well beyond 200 yards in the little 358 Winchester, managed to split the jacket and spit the core after striking a major leg bone.



Here a Grand Slam fired from a 7mm-08, a 145 grainer, also split and shed the core against the shoulder of a caribou at over 100 yards. This is the old dual core GS. I do like the GS though in spite of this incident.

Where do the Remington Core-Lokt bullets fit in? I know Bob Hagel spoke highly of them in his Practical Ballistics book. Of course, that was almost 30 years ago.

I have a lot less experience than muledeer, but I have to agree 100% with his results. What he has listed there mirrors what I've seen.

I�ve never had a problem with a Hornady Interlock or a Speer Hot-Cor. I have noticed (anecdotally) that the Interlock tends to exit more often than the Hot-Cor, but honestly both have always delivered dead game to me.

It�s been well over a decade since I�ve hunted medium-large game with the Remington Cor-Lokt in anything other than .30-30. My experience in the past was that the terminal performance of the Cor-Lokt tended to be nearly identical to the Hornady Interlock. I tended to prefer the Interlock because it was consistently a more accurate bullet in my rifles.

I might go on to add that I�ve never been able to detect a difference in terminal performance between flat base and boat tail. I�ve encountered core separations in both, but I haven�t necessarily seen that one is more prevalent than the other�Again, this is anecdotal evidence; I haven�t actually kept written records.

My Other Brother Darrell has kept detailed records for several decades (that must be why he's a gunwriter and I'm not <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />.), and reported in one article that the incidence of core separation in boattails was no greater than in flatbase bullets.

And I have to agree with my friend from north of the Circle -- I think the Speer BTSP is a little "softer" than the flatbase, but I also think it's a great bullet for deer-sized game. I killed two Sitka blacktails with the 7mm 130 gr BTSP loaded to just over 3000 fps in a .280 this past November, and will happily take it hunting again. It makes these tiny little groups... <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />)

All the core separations I've seen were in bullets taken from dead animals... <img src="/ubbthreads/images/graemlins/cool.gif" alt="" />.

I thought of the little Speer BTSPs when I saw MDs article about FB vs BT bullets because, while I do not have the same depth of experience as he does - or even close, it has mirrored what I have seen.

I have tended to think along the lines of what KevinGibson said about te Core-Lokt though. I haven't used them nearly as much as the InterLock because the IL is such an accurate bullet, while it seems the C-L is sometimes spotty in that dept. I have gotten very good results when I have used it though. Two of the C-Ls I really like are RN with the heavy, tapered and scalloped jacket: the 170 for 30-30 and the 220 for 30-06.

Here is a light-for-caliber 200 grainer recovered from a caribou, a 200 SP fired from a 358 Win.



The Remington jacket has always seemed a bit harder to me than the Hornady alloy/temper, at least in their pointed bullets.

As "Darrel's other brother" says, sometimes one finds a jacket separation - in a dead animal. That reminds me of the fact that it is so easy to get stuck on what the target does to the bullet rather than what the bullet does to the target. In spite of the sometimes "pretty pictures," of bullets (like I just posted), they ain't what "happened."

I would rate the same bullets exactly the way Darryl did.

I have also talked to some bullet manufacturers and found that one reason the Hornady Interlock works so well is that Hornady uses a slightly harder lead alloy than most other bullet makers. This was apparently the reason Hornadys had the best reputation for penetration even before the Interlock design appeared. (Yeah, I was shooting them back then, which dates me some.)

Speer's boattails are not Hot-Cor, but swaged. They use a softer alloy for the boattails, for that very reason. The Hot-Cor process does not bond the core to the jacket. I have seen them separate (one at the entrance hole on a whitetail) but not very often.

The Grand Slam these days is essentially a heavy-jacket Hot-Cor. They simplified the manufacturing process a couple of years ago and it is no longer as tough as the dual-core Grand Slam of a few years ago.

Remington changed the manufacturing process on the PSP Core-Lokts a number of years ago. They now have jackets about like most other cup-and-core bullets, not the very thick sidewalls of the original Core-Lokts. The round-nose Core-Lokts still have the heavy sidewalls--or at least all the ones I have sectioned do.

For a while Remington was using Interlocks in some of their ammo marked Core-Lokt. I don't know if this is still the case since the advent of the Core-Lokt Ultra Bonded.

JB

Because of this, I'll be switching , probably to TSX's, when my supply of older GS's run out. But that might take a while.

Here's a test I did last summer on .35 cal bullet from my Whelen with Hornady, Speer HC, Speer GS and TSX.

Test media was wet newspaper.
Impact velocity: approx 2500fps for the 250gr and 2650fps for the 225gr.

Side by Side view of the exit hole after approximately 6" of penetration. The first one is Speer GS vs Barnes TSX. The second one is Honady IL vs Speer HC.




Hornady 250gr SP IL

Penetration: 17"
Expansion: 0.802, 0.793, 0.792....avrg: 0.803
Weight retention: 206.2, 206.0, 204.2....avrg: 205.1gr



Speer 250gr HC

Penetration: 18"
Expansion: 0.670, 0.796, .0774....avrg: 0.747
Weight retention: 173.8, 217.8, 209.5....avrg: 200.4



Speer 250gr GS

Penetration: 18"
Expansion: 0.656, 0.700...avrg: 0.678
Weight retention: 208.3, 212.8....avrg: 210.6
(one bullet got away)
[img]http://www.imagestation.com/picture/sraid209/p504d3d7d5478e3b2d1cf56048dcc2cf7/ee15397c.jpg[/img]
[img]http://www.imagestation.com/picture/sraid209/p14232d8de1657d2311ad283f8749ed1e/ee1536a2.jpg[/img]


Barnes 225gr TSX

Penetration: 20"
Expansion: 0.737, 0.755, 0.686...avrg: 0.726
Weight retention: 225.1, 225.0, 224.9...avrg: 225.0
[img]http://www.imagestation.com/picture/sraid209/p8cb9ecec78b0631396650d6b06ed4a3c/ee153a2e.jpg[/img]
[img]http://www.imagestation.com/picture/sraid209/pf78678817795fb900a3851cad10ee986/ee15359e.jpg[/img]

I have shot, and seen others shoot, a lot of really heavy game with the 250 gr Speer spitzer.

358 Win, 35 Whelen, 358 Norma Mag, it just plain works! <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />

Ted

Nice test Steve!

Quite candidly, the only bullet test I ever put any faith in is the dead-animal test.

When it comes to the Hornady Interlock, and the Speer Hot Core and Grand Slam bullets, I've mixed results. Accuracy has often been incredibly good. Terminal performance has NOT always been so good, and I've had a number of these bullets, including the Grand Slam, come apart on game, limiting penetration.

So fundamentally I don't use any of these bullets for hunting anymore, even for deer. My basic all-around bullet is the Nosler Partition. It kills deer just as well as the other bullets do, and on bigger, tougher animals it works much more reliably in my experience, plus in most rifles it shoot very, very well in its own right.

I have plenty of reasons to stick with the Partition as well as other premium bullets that equal of even exceed its performance, and fewer and fewer reasons to run with Hot Cores, Interlocks, Game Kings, etc.........

AD

I test bullets both in game and various media, but gave up on wet newspaper long ago. Not only is it a PITA, but it does not stress bullets very much--the reason many bullet manufacturers used it for years: The bullets always came out looking pretty.

Dry newspaper more closely tests what might happen if the bullet struck heavy bone. In a test with recent 200-grain Grand Slams, loaded in a .300 Winchester, 2 out of 5 lost their cores when shot into dry newspaper at 50 yards.

JB

That matches what I would expect, with their change in composition. Two curiousity questions:

1) Did you test original-style Grand Slams side-by-side?

2) Did you test comparable Hornady Interlocks?

Thanks...

There are actually three generations of Grand Slams, the originals (which were tender), the middle generation (made up until about 2-3 years ago, which worked great), and the latest.

The middle generation always worked fine on everything I tested it on, whether animals or any sort of test media. They acted very much like Nosler Partitions, both in retained weight and how wide they expanded.

In dry paper, Hornady Interlocks will generally hold together, though sometimes you find the jacket and core side-by-side. But they peel back a lot further than bullets like the Partition and the middle-generation Grand Slams.

That said, I have never had one come apart at the ENTRANCE hole on game, as has happened on a few occasions with standard cup-and-core bullets. On deer-sized game, I am far more worried about that sort of separation, than finding both core and jacket slightly apart on the FAR side of the vitals.

Also, of course, how well the Interlocks hold up depends on size and impact velocity. But I have generally had very fine luck with them on all sorts of game, in calibers from .25 to .375, given some reasonable care in choosing the right bullet and cartridge for the job.

JB

John B, I just sent off for your new book. Are these topics covered in detail? I am hoping for a an in depth look at the partition as possibly the best "all around" bullet out there today. I know, I know, aint such a thing!!!

In the mid-nineties I did my own dry paper test not because I knew as MD states that it is more reflective of tissue resistance but because over the two days I conducted it I didn't want to haul water out to the site and then haul all the wet garbage back home again when finished.

I used most of the recognized premiums at that time, the Nos Part, Barnes X, Swift A-frame, and non-prems, the Horn Interlock and Speer GS, all in .338 and for interests sake a 250-gr Barnes .338 solid. These were all out of my .340 Wby at about 40 yds and were 225-gr except the solid and the GS which was also 250-gr.

Penetration of most wasn't as good as your wet paper test but the X (~98-100%)beat all at 18", followed by the Part (60-70 %) then the A-frame, then the GS with the Interlock going maybe 8". The GS and the Interlock came apart. This was tightly packed, dense magazine paper, 30" of it snugged in a box with a .25" cast iron plate behind it. The solid by the way traversed all, breaking through the cast iron sheet also and whizzed away.

Bottom line from that point on was I used Nos Part for game and recently incorporated the TSXs in my loads for game because they are the most accurate of all presently in a .30-06, .270 Wby, .340 Wby, .375 H%H. None of my rifles liked the original Barnes X which were erratically inaccurate and the Swift acted like a less efficient but slightly different--retained more weight-- copy of the Part. The exception in game use is the Sierra 140-gr Game King in my moderate 6.5x55 for whitetails otherwise I use Sierras or Hornady Interlocks for practice in weights equal or close to the TSXs I use for game loads. There is no doubt they--the non-prems-- work for game if applied right but I try to keep things as simple as can be and use as few bullets as possible and that means the Part or TSX for me. I'm not a writer so don't have to have broad experience with bullets on game. Bullets are the first thing not to scrimp on when forming a load for hunting.

With my limited experience, I have to agree with Mule Deer's assessment of Interlocks. Although I've only shot at deer-size game, friends have used the Interlocks in various calibers on elk, caribou, bear, and plains game in Africa with uniformly good results, and all the accuracy you could want.

Kept at a reasonable MV, the InterLock is a wonderful bullet. And, I have seen the InterLock ring work, and work well, on recovered samples. As a general rule, though, I wouldn't shoot it in any belted cartridge if relatively close-range shots were a possibility.

Ironically, Weatherby has Norma load the InterLock as the standard bullet in their ammo. I always thought a Partition would be a much better choice in that line.

scott

Once again, here is an attachment with graphs derived from Gary Scuiscetti's exhaustive tests of several bullet types. According to his test, there isn't a dime's worth of difference between the major "standard grade" bullets. They all work well between 2100 and 2800 fps. Below that, they don't open, and above that, they tend to fall apart.

Vertical axis is penetration in inches, and horizontal axis is impact speed, in fps.

Our very experienced Dogzapper has also used Horn Interlocks IIRC with very good results and that should not be forgotten--that they can be used successfully and on big game. But considering the options I've just decided to go with those whose structure promises more integrity in the most situations.

RSY-

I always thought that was odd too.

Amen brother! That is a solid mouthful. <img src="/ubbthreads/images/graemlins/blush.gif" alt="" />

Is John's new book on bullet out? Where do I get it?

Contact his web page or send him a PM. He told me he is getting them in any day. I sent him my $$ already. Here is the thread with his web page that Rick Bin posted:
https://www.24hourcampfire.com/ubbthreads...;page=0#1204357

Thanks for the link. I'll keep my eyes open for when its up for sale on his site.

denton, somehow I missed your attachment with the graph. very informative. Thanks.

Beginning in the early 70's with a .300 Win Mag, I used many 165 gr (non-interlock) Hornady Spire Points on deer (over decades and at a mv of frequently well over 3200 fps). The bullet simply bored a nearly 3" tunnel through deer at distances shorter than a couple hundred yards. I've had similar performance from the later Interlocks and the Speer Hot Cores, but not quite as dramatic.

The two bullets aren't much different, it seems to me -- both are tougher than the old Hornady's.

For a fact, I shot a few deer with Nosler's 165 BT at the same initial velocity and found that bullet tougher than the others. Go figure. It acted like a strong 180.

Although this may apply to another thread more so than this one, the .270 WCF with about any 130 gr bullet has yielded more "drop right there" shots than most bullets out of the .300 WM at similar ranges, unless the old Hornady's are allowed for the 165's.

A standard 150 cup/core out of a .300 WM can be be dramatic, but I've done it enough to not really like it. By and large, I think a decent 130 gr bullet from a .270 does as well or better.