Flat nose vs round nose solids - What are the actual facts?

[Nhoro]

Assuming you are talking about where you saw the photo which prompted the question concerning hanging wet print. Thing is, no photos of my test boxes were posted before your comment asking about that? I was just curious about how you came to that conclusion is all....................

I have seen your thread on another forum and I also think I may have confused your setup with another member that did something similar here. He had the same box but hung paper over sticks I think-like curtains.

 

[Nhoro]

Percentage of Caliber is measured by diameter of the meplat.

Ok-then it appears Peregrine have enlarged the meplat since your test. How do those Hornady DGS bullets work ? Seeing as they are a fmj with a meplat-even though it is a bit small ? I only have them as dummy rounds, never shot them.

I know you use a Winchester M70 actions and flat nose seem to feed in those but CZ 550 are a headache. And I am pretty sure most actions are similar. Most controlled round feed actually bounce the point of the bullet off the edge of the chamber mouth. So flat noses hook up. I read somewhere that winchester cone the chamber mouth slightly and so it feeds better. Anyway, my CZ 550 has been worked on until I think I am there-it feeds The Peregrines about 100/100 times so far. I figure they are about half way between Barnes and GS customs in the feeding difficulty stakes.

 

[michael458]

How do those Hornady DGS bullets work ? Seeing as they are a fmj with a meplat-even though it is a bit small ?

Hornady DGS, yes, I have tests in .510 caliber and .458 caliber with the Hornady DGS. Meplats measured 55% of caliber, so they are less than optimum. They also come up very short in the "Construction & Material" factor, in fact, they are pretty weak in that department. These test were conducted probably around 2009-2010 or so. I am not aware of any changes to these bullets, nor concerned about any. At the time Hornady did the 55% meplat so it would feed better in Ruger and CZ Rifles. This was a common pet peeve of mine with Hornady, among other things.

The vast majority of the Solid Research was done with my test partner and life long friend Sam Rose in NC. Without Sam the extent of the research just would not have been possible, nor nearly as extensive. One of Sam's great attributes was that he is a master machinist and was able to actually make small quantities of various bullets that we tested. We would test one week, he would go home and make some changes to a bullet, and or we would come up with a totally new design. We literally were able to test nearly everything your imagination can come up with.

Sam is a big double rifle fan, and he desired a proper designed solid that would not only do well in the terminal performance arena, but also be easy on the delicate barrels of double rifles. Much was noise was made about solid bullets and how they damaged double rifle barrels, so we decided to put some of these concerns to rest if we could.

Fortunately I also run Pressure Equipment here, and use strain gages. We decided to measure "Barrel Strain" on double rifles, to see what effect various different bullets had on a barrel. We were able to attach a strain gage on the barrel, 4 inches back from the muzzle, and measure just exactly how much that barrel expanded at the passage of that point with any bullet. It was an eye opening experience for both of us, and we learned a great deal about that. We started playing with different bands on various bullets and configurations. This research ultimately led to the bands on the current CEB #13 Safari Bullets, with 3 top bands and one bottom band. This proved to be the best in accuracy, ease and variable points for loading, and of course very low barrel strain and expansion of the barrel itself, the best of all worlds.

Below is a very early Copper Version of the CEB #13 Solid that Sam made and we tested, both terminals and barrel strain. This is a early Two Band version, fired in 500 Nitro and tested in a double rifle. The reason I post this, I just ran across it in my photos looking for the DGS, and honestly thought it would be a good comparison as it is designed properly. But, with that, I had to also explain the two bands and the development of that extra research. Apologies for the longevity........... I am sure it can get boring to some............

 

[michael458]

In .458 caliber tests done the 500 gr Hornady DGS did rather well in the tests conducted with a 1:14 twist rate 458 Lott.

But, in the more demanding heavy T'Rex tests, that consisted of Cement blocks, it showed its "Construction & Material Factor" weaknesses.

And of course that weakness of Construction showed up here in the real world on elephant.........

In another test later the Hornady did not do quite as well and lost stability, and I can't remember exactly the circumstances.

 

[michael458]

The 500 Hornady showed some inconsistencies, which would have been expected with 55% Meplat of Caliber. The unexpected was the one test with good performance.

I also tested the 480 gr Version, it did not do well at all........ and possibly caused me to retest the 500 gr version..........

 

[PHOENIX PHIL]

The DGSs with the flattened tails if you will, they bear resemblance I believe to some of the solids @gizmo recovered from a lion.

 

[Nhoro]

The Hornady bullet are in dummy rounds that a friend made up for me-never shot them. I was just interested because they are essentially a fmj flat nose solid. I measured those same dummy rounds -to tell you the truth they have been used so much that they look like your cinder block subject so the meplat is probably bigger- or maybe they upgraded. I read somewhere that Hornady had made the jacket thicker and maybe the meplat bigger.

With regards current bolt action CRF actions (probably including winchester), they are mass produced to fit anything from a 375 to a 500 Jeffrey. The difference in case head size and taper and length will tell you that compromises are made.Mauser himself layed out the maths to get magazine width and 60 degree stack angles of the rounds in the magazine and straight feeding into the chamber.Military rifles were fine because they produce millions of rifles for one cartridge and use spitzers.They get it right once and then copy. It only goes wrong when cheapass manufacturers produce the same basic rifle and screw a different barrel and magazine box on it.Different diameters,different tapers, different stack angles for each calibre. And so bullets do not feed directly into the chamber, they bounce off the chamber mouth- Winchester included but they have coned the chamber mouth. So basically you need to have a gunsmith adjust your rifle or DIY to feed flat nose solids. Push feed rifles generally don't have this problem because they have a different loading mechanism.

So, in my opinion, round nose solids are more because of poor rifles than any performance advantage/disadvantage. It is basically the result of cheap manufacturing.

 

[Nhoro]

So this thread has sprked some research on my part-Basically because I just want to know the science of it.We know from empirical evidence that flat noses penetrate more. However many things have bugged me about supercavitation theory for bullets- quick summary below:

Supercavitation:

1/This seems to have been generated by a single (theoretical) article published by a guy using Kursk submarines theory. It may be true but I was not able to find any scientific papers to do with bullet penetration. Scientific papers all seem to use penetration models without any reference to supercavitation.
2/ Also a simple high school science-energy to boil water calculation predicts that supercavitation would result in 297 m of penetration in water-clearly not happening, even with efficiency losses. It would also raise the temperature of water to above boiling- any efficiency losses from the above calculation would be obvious when the water in the wet pack/ballistics gel boils away-lots of steam if you consider 60 " penetration (1.5 m) would result in the energy loss equal to 295.5 m of penetration.
3/ Also a problem with supercavitation is the fact that the round nose solids penetrate 40 + inches and probably more in a CURVE or at various angles. They also often tumble and therefore lose penetration. If FN supercavitate then why do round nose penetrate 70 % of the distance in a curve or at an angle.

So my thoughts are illustrated by the following test: Take a loaded cartridge FN and RN and balance them on their nose. FN- easy RN- Not so much !

 

[Nhoro]

So shamelessly cribbed from a scientific paper 'Projectile Penetration into Representative Targets by George W.Stone.

Essentially penetration is governed by 3 factors:

1/Fluid dynamic drag : This is proportional to velocity squared. so as velocity increases fluid drag increases even faster.

2/Kinetic friction on the surface of the projectile

3/ Deceleration forces caused by the target material ie concrete is harder to penetrate than ballistic gelatine

With hard items (bone), there is almost no fluid so penetration is dependent primarily on the material being penetrated (3)and friction(2). This is why round nose and flat nose penetrate the same in hard materials. Shape only impacts how much friction the bullet experiences and that is similar for FN and RN.

With meat?wet pack/ballistics gelatine, all 3 factor impact penetration. However, target material is largely water so Force (3) is amost the same for FN and RN. (2) Is also similar and (1) is also pretty similar IF the bullet remains front on and does not yaw.

So the reason that RN lose penetration is primarily stability. they begin to yaw and then stop. There is also some discussion about FN 'punching' a hole ie using shear forces and cutting out a circle while RN burrow their way through flesh. So IMHO, the real difference between FN and RN is the stability of the shape during dynamic penetration and I can see that illustrated by simply balancing a bullet on its point. Gravity pushes the bullet down and the table pushes up. It will be a picture of the forces happening during penetration.

michael458 say that bullet are 'front drive' when they hit flesh or wet pack. That is his intuition saying essentially the same thing-nose shape gives stability or instability during penetration. Yaw and tumbling reduces penetration and so FN out penetrate RN.

 

[RayAtkinson]

Many years ago as a young man, I observed the effects of the Keith simi wadcutter on game as compared to other configurations with the 44 special and later the 44 Magnum. I also came to a conclusion this same effect might apply to big bore rifles as well..I wrote letters and got on the phone to a number of bullet makers and was met with scolding to humor, and the best I got was a free box of solids that had the nose ground flat, so I used them to shoot a couple of buffalo and the results were excellent, so I renewed my vision..Then one day I contacted Gerard of GS customs and he actually had a flat nose solid, then I talked to a gent in Or. that sent me about 500 flat nose solids with my suggestion of a cutting shoulder such as the Keith bullet, then mike at North Fork made me some flat nose solids to test on buffalo and the results were outstanding and led to the "Cup Point" the best buffalo bullet ever made in my opinion, and one Ive used often on buffalo along with the flat nose solids..
Im not a scientific type of guy, just a hunter who has hunted AFrica as much as anyone I know over a 40 or 50 year span, and all my results are based on being up to my elbows in guts and blood looking for that bullet, an old bullet digger..

My results is the flat point solid is the better bullet and there was never anything wrong with the old Hornady or Woodleigh round noses as to straight penetration but the flat nose did more internal damage and killed better...

The bullet makers have come a long way since those days of yesteryear, and there are a number of great bullets today that will give strait penetration and we need to praise todays bullet makers as its no longer a question, is been fixed! I never did get that keith design in a rifle bullet, but they got damn close, good on'em!

 

[Bullet Safaris]

Great thread with excellent information and a lot of research. Thank you.

Now... i need to go back and read it all again before I start asking questions!

 

[Nhoro]

michael458- Did you ever test a flat nose with a very slight angle machined on to the front-essentailly a very flat cone with a shallow angle like 5 degrees ? Just thinking that would probably allow it to feed like a round nose. It wouldnt take much of an angle to get it around the corner.

 

[michael458]

michael458- Did you ever test a flat nose with a very slight angle machined on to the front-essentailly a very flat cone with a shallow angle like 5 degrees ? Just thinking that would probably allow it to feed like a round nose. It wouldnt take much of an angle to get it around the corner.

No, I don't think so. Sounds to me like that would reduce the actual meplat size................Frontal area.......

Not only that, but here we go trying to "Fix" a bullet, to work in a less than desirable gun, in my opinion. Fix the damn gun. And don't screw with a proper designed bullet! If the damn gun won't function, throw the damned thing in the trash and start over....... Now, sorry, apologies, that is purely my opinion and exactly what I would do, and its worth what you paid for it, end of story.............

Just today, loading some proper solids.................BTW................

 

[Nhoro]

So just got back from the range. finally opened after lockdown and it was bedlam ! Anyway checked my zero on my 458 (sights were soldered at an angle at the factory so had it fixed over lockdown) While I was there, I talking to the guy who taught me reloading/does Proguide and Prohunters shooting tests. He has a model 70 458 Lott cored out from win mag and it will not feed flat nose bullets if you work the bolt quickly.My CZ also bumps the flat nose into the chamber off the chamber mouth if you really put some muscle into the bolt.I have spent countless hours over the last 6 months to a year to get absolute confidence in my rifle feeding flat nose solids. I know that many PH's use woodleigh RN because they feed reliably NOT because they penetrate, so that means that people recognize that reliable feeding is a necessary requirement of a bullet. As a client hunter, maybe you can choose performance over reliability but Pro Hunters have a more difficult choice-you are the last line of defense !

 

[michael458]

Thus far we have not really touched on just how effective the Flat Nose is when it comes to hitting things HARD up front. I have shot a good many buffalo, and in the early days regularly used Round Nose Solids, like most of us have. Mostly used those in .458 caliber. I normally also used the Barnes RN solids as well. I never once saw a buffalo paying much attention to taking one of these. There was little or no reaction. In 2005 I was in Tanzania with 458 Lott and the new Flat Nose Barnes solids. Using 500 gr Swift A and 500 Barnes FN for buffalo, after the first good hit with the Swift, buffalo buck up and run a distance, then hit them with the solids at the first opportunity. I had 3 buffalo on quota, and each time hit with the Solids the buffalo paid attention, and two of those hits were DRT with the FN Solids. It was very noticeable differences in the reactions of buffalo. From that day forward, I was 100% sold on this, and would never turn back.

One would not call me a "Tree Hugger"........ I am a fairly serious "Tree Killer". On nearly every hunt I went on, somewhere along the way I would do my best to kill a tree. Like many times before, I test things before going to the field. We did a stick test here on the range with several different solids, just to see what would be thrown off and what would hold out the best. In every test the FN solids always won out. And, the CEB #13 and the North Forks were at the top of the Class when it came to busting through brush and trees. I learned this in the field as well. Somehow, tunnel vision takes over with me, and I never see trees, all I see is buffalo.

On one trip I was using one of my 50 B&M Alaskan Lever guns for buffalo. First shot was a 365 gr Lever Raptor at 2200 fps. Buffalo was running in front of me, left to right. I was never a good running shot, so aiming for the shoulders, hit just behind the shoulders taking both lungs out. Buffalo had a head of steam up, so I levered one of the Solids up, 405 gr #13 Lever Solid at 2120 fps, and turned it loose. Hit the buffalo dead center of the guts, and he made the thick brush before I could get another one in. Long story shorter, I managed to work my way around him and wore him out with 4 more solids, rocking him back with each one until the battle was done.

Now this particular hunt was being videoed. Back at camp with the camera directly behind me, we actually saw that first solid going to the buffalo and saw that it hit dead center a 3 inch or so diameter tree about 10 yards in front of me. Bullet hits tree, drives straight to the buffalo, and centers the guts, then exits the buffalo. Next day, we went back to the scene, found the tree, and I paced off 30 steps behind the tree where the buffalo took the bullet. That is a long way for that bullet to go and not veer off after hitting the tree...... I was rather impressed with that.

This is the tree that it busted.

Now, the very next year I found myself back in Zimbabwe with a 500 B&M. This is .500 true caliber, rather small for its capacity, running a 18 inch barrel. Cartridge is a specially designed 2.5 inch RUM case, and the rifle a Winchester RUM action. For this I was using a 410 gr CEB Raptor at 2500 fps and a 450 CEB #13 Solid at 2400 fps. I shot this cow buffalo at 50 yards, first shot with the Raptor on point of left shoulder, off set frontal shot. Damage was so devastating the cow could do nothing but turn 180 degrees and stand there. Now I put the 450 Solid dead on the shoulder, and down went the buffalo DRT on the spot. End of story....... Until.............

I went directly to the buffalo, made 100% sure nothing else needed attending. While looking down at the buff, my Son called out that I had hit a tree just a few feet in front of where the buffalo was standing when I shot with the Solid. I turned, looked, could not believe what I was seeing. Closer inspection showed the 450 .500 caliber solid had indeed centered the damn tree, it then exited, hit the buffalo square on the shoulder, where I "Thought" I was aiming, and where I "thought" I was seeing. The bullet hit buffalo, and went completely through, and still may be going for all I know. There are two very amazing things about this, ONE.... This was not a small tree, it was 10-12 inches in Diameter, and was between me and the buffalo.
TWO... It hit the tree so damn hard, it knocked the bark completely off one side. So you know it knocked the hell out of that tree.

There is one more thing, that I do not understand to this day, and probably will never figure out. How did I see that buffalo shoulder, clear as day, and to this day in my minds eye, I still see it, and never once did my eyes, nor my mind register this tree? I don't know? Can't tell you!

Take a look at this tree...... and what that bullet did to it............

Enjoy your day........................

 

[michael458]

As a client hunter, maybe you can choose performance over reliability but Pro Hunters have a more difficult choice-you are the last line of defense !

Yeah, well you do as you please and believe what you wish..................

 

[Forrest Halley]

Personally I trust no one else to be my last line of defense. That's just a shameful testament to the fact that you weren't prepared to go hunting what you went hunting. No thanks.

@michael458 if you didn't shoot so many trees you wouldn't need all that bullet help. Now we know the real reason you're after all that muzzle energy. You're a Stevie Wonder Lumberjack!

 

[michael458]

Personally I trust no one else to be my last line of defense. That's just a shameful testament to the fact that you weren't prepared to go hunting what you went hunting. No thanks.

Absolutely 100% Correct....... Any one of my rifles would get 400-500+ rounds fired through it BEFORE the trip. All full house rounds that have the bullets in them that I will be using......
Reliability? Never a question. The world I come from will not tolerate 2cd place, inexperience, or equipment that is not tested, and 100% reliable. To insinuate otherwise to me is nothing but an insult, and taken as such. End of Story.......

@michael458 if you didn't shoot so many trees you wouldn't need all that bullet help. Now we know the real reason you're after all that muzzle energy. You're a Stevie Wonder Lumberjack!

HEH..... Yeah Forrest, you may be on to something there! LOL.................

 

[DWB]

Please share with us how you get a rifle to feed flat nose solids?

Them hitting the chamber mouth is a big reality. Where I do believe the Winchester rifles' chamber mouth is beveled which probably helps.

If I remember correctly @Red Leg has also mentioned before that he has had a few rifles altered to feed these solids?

 

[Major Khan]

In .458 caliber tests done the 500 gr Hornady DGS did rather well in the tests conducted with a 1:14 twist rate 458 Lott.

But, in the more demanding heavy T'Rex tests, that consisted of Cement blocks, it showed its "Construction & Material Factor" weaknesses.

And of course that weakness of Construction showed up here in the real world on elephant.........

In another test later the Hornady did not do quite as well and lost stability, and I can't remember exactly the circumstances.

It is truly disappointing to see how much the .458 caliber 500 grain Hornady solid metal covered bullet has deteriorated in quality , over the years .

Back when I used to be a professional shikaree ( From 1961 - 1970 ) ... Hornady used to manufacture the finest .458 caliber solid metal covered bullets of our time .

Hornady still did not manufacture factory loaded center fire rifle cartridges , back in those days . They would only manufacture bullets for re loading , back in those days . These were available as re loading components ... Back in those days.

Hornady used to produce a .458 caliber 500 grain solid metal covered bullet ... Which used to utilize a round nose ( As opposed to the flat nose design , which I am seeing in your photograph ) . It used to feature an impressively thick steel " Jacket " and was extremely robust in construction .

I have recovered countless of these Hornady .458 caliber 500 grain round nosed solid metal covered steel " Jacketed " bullets from the corpses of 3000 pound male gaur bison . How ever , I clearly recall that very few of them were so badly distorted ( I certainly recall recovering no more than 9 such bullets ... Which were badly distorted ) .