Bullet construction

I'm asking about Round Nose (RN) Core Lokt specifically.

When it comes to impacts under 2000fps, these (and other round nose bullets in general) have yielded significantly different, and significantly better on game performance than Spitzer (typical) type bullets in my experience
 
I'm asking about Round Nose (RN) Core Lokt specifically.

When it comes to impacts under 2000fps, these (and other round nose bullets in general) have yielded significantly different, and significantly better on game performance than Spitzer (typical) type bullets in my experience
I should have clarified more on the Core-Lokts.

These, in general, are definitely a popular hunting bullet, but it's no secret that their popularity is mostly with your "average" hunter and used typically at close to medium distances. And I mean no offense by they or that there's anything wrong with that. Many very experienced hunters use them too and that's great.

If you wanted to hunt more often at medium, and definitely at long, distances you'd find these tend to struggle immensely with accuracy and terminal performance. After cross-sectioning them, you can get a better idea why that is.

First off, the core is only "Lokt" by a crude cannelure. These aren't an actual bonded bullet. That said, the cannelure is placed pretty much in the center of each bullet and it's allowed the jacket to slightly un-swage from the core, and unevenly (areas circled in the pictures). The cannelure tends to create an uneven crimp into the core as well (what the arrows are pointing out).

All Core-Lokts, to my knowledge, are flat based as well. You can see that even the base is uneven in thickness. The round nose version is also very uneven at the opening of the jacket where the lead core spills over and is exposed.

All these inconsistencies, that when fired and spun at high RPMs, can or do result in the bullets inducing an imbalance in flight. The longer the flight (distance to target) the more out of balance the bullet becomes. It'll yaw like crazy and end up impacting untrue- sometimes even keyholing. I'm not saying that happens often, but I've seen it personally in more than one rifle abd with more than one variety of Core-Lokts.

I was surprised by the overall jacket thickness. They're definitely not the thickest jackets I've seen, especially with typical "hunting" bullets, but they're not that thin either.

To me, these are really just cheaply made bullets that'll get the job done if you're only hunting at distances typically 100 yards and in- which there are TONS of hunters out there that never shoot at an animal farther than 100 yards. They're nothing special, and they're definitely not to the quality a long range hunter should strive for, in my humble opinion. There are simply better choices out there for that.

When it comes to impacts under 2000fps, these (and other round nose bullets in general) have yielded significantly different, and significantly better on game performance than Spitzer (typical) type bullets in my experience

If at closer distances and impacting below 2000fps, yes they'll work great. My point I was trying to make was that they can be very challenging to get to shoot accurately at longer distances. A round nose is not an inherently high BC bullet though and it's not going to get too far in most cases by the time it gets to 2000fps or less.

The wide frontal area of a round nose will indeed produce more potential for expansion, and at lower impact velocities than your typical spritzer. That's true. I even run the 117gr Hornady round nose in my go-to rifle for hog hunting because most shots are close range where I hunt them and it's a great balance in regards to expansion versus penetration for them.

So to be clear, when accuracy at longer distances, as well as lower impact velocities isn't detrimental, a round nose can be a great option. There are indeed circumstances where they still excel. Like I've said, all bullets have merits and their own strengths and weaknesses.
 
First off, the core is only "Lokt" by a crude cannelure. These aren't an actual bonded bullet. That said, the cannelure is placed pretty much in the center of each bullet and it's allowed the jacket to slightly un-swage from the core, and unevenly (areas circled in the pictures). The cannelure tends to create an uneven crimp into the core as well (what the arrows are pointing out).
Although this is an old thread, I wanted to point out that in addition to the cannelure, a feature of many Core-Lokt bullets is a flair in the core near the base from a thinned section of the jacket. It is subtle in many instances, but shows up in the photos of the round nose bullets sectioned by Petey308 (top photo, circled in red). Some of the bullets have a core with a more pronounced "hourglass" shape (which showed up in some older advertisements), but some just have the small section at the bottom of the jacket. This very small thinned area can be seen at the bottom of all three sectioned bullets in the second photo. Oddly, this thinning of the jacket exists even in bullets that have other core-retention mechanisms. The Core Lokt Tipped bullets appear to also have a Hornady-like interbond lip above the core flair, both of which are more clear in the third photo. The Core-Lokt Ultra Bonded bullets, for some reason, have even larger sections of thinned jacket near their bases. It is more exaggerated on the Ultra Bonded Core-Lokt (extreme left) in the bottom photo.

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Core-lokt-v-core-lokt-tipped.jpeg

core lokt tipped.jpeg

Core lokt ultra bonded.jpeg

ultra bonded corelokt scirocco Rem solid Aframe.jpeg
 

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Glad this thread resurfaced. I just read it "cover to cover." Interesting read @Petey308.

I started reloading when I was ~12 on my dad's bench. I just turned 45 in January and haven't stopped loading and hunting. Although, I'll admit I've taken some breaks in between due to a tough schedule at work here and there.

In that time, I have found the best terminal performance for me has come in this order.
1. Monos and bonded bullets
2. Cup and core designed to mushroom
3. Cup and core designed to fragment

#3 is a distant third from 1 and 2 from my experience. This is why Bergers stay at the range for me now.

Interestingly enough, I've never hunted big game with a "target" bullet. So, I won't bash them on game as I don't have the data to do so. It seems like many members have had good luck using match bullets which I find interesting. Yet, I'm still not convinced that's a good route for me.

I'm glad to see you included the Sierra HPBT GK. One of the most overlooked bullets IMO. Probably because of the lower BCs. It sure does kill stuff with authority though.

Nowadays, with a ballistics app, you can pretty much get decent performance out of most bullets as long as you stick to the manufacture's recommendation for terminal performance on the low side. Plug in your variables and wham, you have your max range. Don't take shots over the calculations and you'll have freezers that look like this:
IMG_0503.jpeg
 
In that time, I have found the best terminal performance for me has come in this order.
1. Monos and bonded bullets
2. Cup and core designed to mushroom
3. Cup and core designed to fragment

#3 is a distant third from 1 and 2 from my experience. This is why Bergers stay at the range for me now.
I learned a lot from this thread, especially that polymer-tipped match bullets like the ELD-M tend to mushroom and do well for hunting. I was under the false impression that the jacket needed to be skived to peel back for a good mushroom. Apparently, just having a polymer tip is good enough.
All of my previous experience with match bullets was with the older OTM or HPBT designs that usually needed to yaw to break the jacket before lead was exposed to expand and/or fragment. Previously, I had thought that the tipped match bullets would likely act the same way.
Another big thing is that apparently Hornady's patent for the Interlock Band has expired. It showed up on a couple of other bullets here including a Norma and Remington.
Thank you Petey308!
 
Question about post 2011 Bergers. Are you saying the jacket on them was changed in 2011? I am asking as I have some VLD's in 7mm 180 gr that do great on bear/heavy game but just pencil through a deer with little to no blood trail and seldom a dead right there impact. Deer would carry the VLD off 80-100 yards and in thick dense woods that is a problem with no blood trail, and hungry bears around.
 
Question about post 2011 Bergers. Are you saying the jacket on them was changed in 2011? I am asking as I have some VLD's in 7mm 180 gr that do great on bear/heavy game but just pencil through a deer with little to no blood trail and seldom a dead right there impact. Deer would carry the VLD off 80-100 yards and in thick dense woods that is a problem with no blood trail, and hungry bears around.
Yes, they had to thicken the jackets due to issues with the increased friction from the faster twist barrels and that heat produced transferring through the jacket and into the lead core, melting it. They'd randomly blow up in flight.

Thickening the jackets allowed less heat getting to the core. The issue though that was produced by that was the ogive portion of the jacket ended up being thicker and would create issues with reliable expansion on game. The more resistance the bullet encountered, the less of an issue, so that why you see/saw those results you spoke off.

All that said, I have seen the new lots of VLDs have internal ribbing applied to the ogive area of the jackets, just as all the hybrid ogive versions do. That ribbing weakens the ogive and allows for reliable expansion with both higher and lower amounts of resistance encountered by the bullet, as well as both higher and lower impact velocities.

Another thing to note though is a VLD ogive, or more specifically any real secant ogive, will be overall more narrow in profile and that in turn adds a degree of strength and rigidity and that will create some resisting to expansion by itself. A more rounded and tangent profile ogive is more ideal regarding terminal ballistics and also internal ballistics, but a secant is more ideal regarding external ballistics. The hybrid ogives have done a decent job at balancing that all. Tipped bullets, as well as monos with features added to help weaken the ogive and promote reliable expansion have helped a lot too.

Hopefully that helps.
 
I hope that I didn't come off as obnoxious on the post about the Core-Lokt's. After seeing your photos, I remembered some older ones clearly showing an exaggerated hourglass shape of the core and started down the rabbit hole.
The inconsistency seen in the thinned section at the bottom of the jackets was interesting and does not inspire confidence in their products. Sometimes you needed to squint to see it and sometimes it could be seen mostly on one side. It would not surprise me if poor quality control and worn-out tooling played a big part with the two bullets that you sectioned. It makes sense that these problems would be worst on products that have been produced for many years and likely still made with older machinery.
In retrospect, it appears that Remington use the same jacket tooling for both the regular Core Lokt and and Ultra Bonded bullets. It makes sense, but probably reduces the accuracy a bit. I certainly was surprised to see the interlock ring, though.
 
I learned a lot from this thread, especially that polymer-tipped match bullets like the ELD-M tend to mushroom and do well for hunting. I was under the false impression that the jacket needed to be skived to peel back for a good mushroom. Apparently, just having a polymer tip is good enough.
All of my previous experience with match bullets was with the older OTM or HPBT designs that usually needed to yaw to break the jacket before lead was exposed to expand and/or fragment. Previously, I had thought that the tipped match bullets would likely act the same way.
Another big thing is that apparently Hornady's patent for the Interlock Band has expired. It showed up on a couple of other bullets here including a Norma and Remington.
Thank you Petey308!
Just having a polymer tip doesn't solve the issues. Not just any polymer tip material works either. How the tip is shaped and how it is married to the bullet along with bullet material, all go hand in hand to make a bullet with a tip work in the widest range of impact vel and shot angles.
 
Thanks. That's gotta be saying a lot lol. I have a similar write-up on solids, but I know that can be a very touchy subject amongst a lot of hunters. I have stuff I've written about reloading as well.
First off thank you for sharing all your hard work.
I would love to see more on solids as they are becoming much more of a thing and I am thinking that they may be a better choice for smaler calibers for more wt. Retention for better penitration with small cal. In my limited experience it's seems the high bc cup and core bullets in small caliber such as 6.5 and under just do not hold up well enough at any relatively close shots. Hence my reason for going to a Barnes lrx for hunting with 6.5.
I am willing to give up 100 or so yards at distance to gain better wt. Retention at close range.
Your (anyone's) thoughs...
 
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