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

[michael458]

And in all fairness some examples of Properly Designed Solids.....................

And could go on and on, but I think you might be beginning to understand.........................Knowing some of these things, what would you choose?

 

[michael458]

Todays hunters are truly blessed with a large variety of excellent bullets. There are many good bullets out there and you will hear me talk most about the Cutting Edge Bullets and the North Forks. Well, fact is, yes I am a bit prejudiced to these two companies. Both worked very close with myself and others that was working with me at the time. Both owners of CEB and North Fork (at the time) were regular visitors with me during the design process of these solids. I worked closely with both to tweak the bullets to what we felt like was perfection. Both are still good friends. Of course North Fork has new owners now, and we hope they continue what John and I were working with.

But that is not all the good bullets available today, maybe the best, but there are many more that will get the job done very well. I urge all of you to choose wisely, and choose better than what yesterdays hunters chose and had to work with. Bullet Tech has advanced tremendously the last 15 years, take advantage of that and use that tech to help you be successful in the field. That is what matters. I was very fortunate to be able to do some of the things we did, and work with the best people to get some of this to you guys.

In all honesty, in some ways it was a selfish venture on my part. I had just developed a series of true .500 caliber rifles back in 2005, and they were not going to be worth a damn to me in the field unless I had serious bullets to match some of the power levels they could achieve. This is what began our search for better bullets, and in particular real and proper designed Solids! We believe we achieved that goal, and put it to work in the field where it indeed proved itself, not just by me, but many many others.

 

[Longwalker]

I have a somewhat foolish question. I understand that it's simpler to just buy the correct bullets. BUT - I have a fairly large quantity of the old style Barnes RN banded solids. Would it be reasonable to set up a jig and machine off a bit of the nose to convert them into flat nose bullets? My understanding from other experiments with nose profile is that variations in nose shape has very little to do with practical accuracy. Has anyone tried "flattening" RN solids?

 

[Forrest Halley]

I have a question about converting brass solids to cupped point. Could you just drill a slight cavity in the nose? A dimple as it were?

 

[crs]

Forrest,
Of course you can. I have been reading all about doing that for a .458 win mag. If interested, I can send you a PM.

 

[Nhoro]

Michael458 I am circling back to something you said earlier about the stability of FN solids coming from moving the centre of gravity forward. Did you ever experiment with steel fmj and trying to move the centre forward- I am thinking with a brass insert in the base or something like that ? Or maybe a round nose with a boat tail ? Just interested to know how much stability is the flat nose and how much is a forward centre of gravity.

 

[DWB]

Excellent topic! Thank you for the comprehensive information.

Regarding Dzombo Solids, reports from the KNP in SA was that when shooting the 600gr .458 Dzombo from 450 Rigby at around 2200fps +/- they achieved full length penetration on large bodied elephant bulls on departing shots. Solid was recovered under the skin on the forehead.

A friend of mine backed up on a buffalo hunt in last week. One x 458WM with PMP Brass solids and one x 458 Lott with Kriek Brass solids. The two PMP round nose brass solids remained in the buffalo (relatively broadside shot), but the two large meplat Kriek solids both exited in lengthwise shots. Interesing comparison from 2 different 458 solids on one animal.

 

[Nhoro]

Also interested when re-reading the peregrine rests thatbthe same bullet at 2150 fps and 2300 basically had same straight line penetration. After that the faster bullet started to lose direction but kept penetrating.

 

[DWB]

With reference to my previous post, here is a photo of the Kriek Solids:

.458 in 500gr and .511 in 570gr

Please note that due to their excellent penetration, none have been recovered by my friend thus far

 

[michael458]

I have a somewhat foolish question. I understand that it's simpler to just buy the correct bullets. BUT - I have a fairly large quantity of the old style Barnes RN banded solids. Would it be reasonable to set up a jig and machine off a bit of the nose to convert them into flat nose bullets? My understanding from other experiments with nose profile is that variations in nose shape has very little to do with practical accuracy. Has anyone tried "flattening" RN solids?

If you can be precise enough yes. I don't have that capability here, and had exactly the same thought in 2006. I did it with a bench grinder, and measured and looked half way good. But testing they were crap. During terminals they were even worse than RN. LOL...... I did not have something right. So I talked to JD at the time and he got David Fricke from Lehigh to do what I wanted, and they did very good. Just needed a precise way to do it. Nahh, nose has zero to do with accuracy....... But everything to do with Driving Straight during terminals.

I have a question about converting brass solids to cupped point. Could you just drill a slight cavity in the nose? A dimple as it were?

Yes, again, precision so one does not mess with stability. Cup Points, Hydros and those type bullets are extremely effective, and very very interesting. Recently I have been testing and playing with the Lehigh Extreme Penetrators, and they are very interesting bullets, and they work. If I were not retired from hunting I would try some of these on buffalo, I have a feeling they would be very effective. Currently carrying some of these in my handguns as well. But that is a whole other category of Solids that have a different purpose.

A friend of mine backed up on a buffalo hunt in last week. One x 458WM with PMP Brass solids and one x 458 Lott with Kriek Brass solids. The two PMP round nose brass solids remained in the buffalo (relatively broadside shot), but the two large meplat Kriek solids both exited in lengthwise shots. Interesing comparison from 2 different 458 solids on one animal.

DWB, I am not familiar with either of those bullets, so do not know the exact properties of either. PMP is Round Nose, and the Kriek Flat Nose. RN does not even exit broadside buffalo, and the FN exit full length end to end shots, same buffalo. Yes, Extremely good example, and exactly the point...so to speak!

 

[michael458]

With reference to my previous post, here is a photo of the Kriek Solids:

.458 in 500gr and .511 in 570gr

Please note that due to their excellent penetration, none have been recovered by my friend thus far
View attachment 351217

DWB, those are good looking bullets. Meplat looks to be proper size, and the edges have a nice radius. I have no doubt those would do very well.

 

[michael458]

Michael458 I am circling back to something you said earlier about the stability of FN solids coming from moving the centre of gravity forward. Did you ever experiment with steel fmj and trying to move the centre forward- I am thinking with a brass insert in the base or something like that ? Or maybe a round nose with a boat tail ? Just interested to know how much stability is the flat nose and how much is a forward centre of gravity.

We took some RN FMJ and gave them a hollow base, moving center of gravity forward, but it did not help at all. Remember, with Solids, they are Front End drive once terminal penetration starts in aqueous medium/tissue, and RN is not stable, there is nothing you can do to make a RN Solid 100% Stable during penetration from beginning to end. At some point it will loose stability and veer off course. The question is, when will it loose stability, at what point, and was it able to complete the mission before loosing stability?

We did some work with Hollow Base Flat Nose solids that was very interesting, but left unfinished.

The Flat Nose penetrate by creating a bubble in any aqueous material. This bubble allows them a free ride so to speak, and maintaining that bubble is where many of the factors come into play. Center of gravity obviously has some importance, however it is not the exact reason a FN penetrates straight and deep.

 

[michael458]

Also interested when re-reading the peregrine rests thatbthe same bullet at 2150 fps and 2300 basically had same straight line penetration. After that the faster bullet started to lose direction but kept penetrating.

This is meplat size and nose profile starting to have effect. In my opinion, only straight line penetration counts. After that it is not predictable. All FN Solids are not created equal.

When it comes to velocity, nose profiles have a large effect. Some Nose Profiles are very reactive with velocity. The CEB and North Forks react well with added velocity. Add velocity and you get deeper penetration. Other profiles, such as the Barnes Banded do not gain as much depth of penetration with added velocity. Still a good bullet, but does not react to added velocity like other nose profiles do. The Peregrine reacted to the added velocity, but the size of the meplat was not able to keep it stable once it lost that velocity at the end of penetration.

I have not seen any new Peregrine bullets, hopefully they increased the size of the meplat, which would stabilize it better towards the end of penetration.

 

[Nhoro]

Also interested when re-reading the peregrine rests thatbthe same bullet at 2150 fps and 2300 basically had same straight line penetration. After that the faster bullet started to lose direction but kept penetrating.

 

[RayAtkinson]

This subject is what I call scientific masturbation! its been beat to death with experts that in many cases have never seen a live wild buffalo...

Ive shot many buffalo , way more than most, Early on many years ago I realized that the Keith simi wad cuter killed better than anything on the market, so why should it not perform on game, and I set about trying to talk the bullet makers into developing a similar bullet for rifles, the best I got was a rondnose ground flat...Later on a gentelman now deceased in Or. sent me a supply of flat nose solids with a cutting shoulder made of solid brass and it hammered buffalo, then we devised a "cup point" that had all the attributes of a soft and a solid, and it killed buffalo even better, I then met Gerard of GS Customs and had a HP monolithic which was a wonderful bullet and he already had a flat nose solid, later I teamed up with North Fork and took his flat nose solid and flat nose cup point to African and shot more buffalo and the flat nose solid was finally accepted throughout the gun world..This was my experience and based on actual kills, and compared to the RN in the field, I never fired another round nose solid, other than Woodleighs in my double rife for a time, and later shot flat nose solids in my doubles..Nothing scientific, some things just need to be proven by results, the rest is twaddle IMO..All that said, the round nose solid is a great solid and it works just fine and all the nay saying is just BS, the round nose has proved itself in the field you many years, that said the flat nose and cup point design is better, simple as that.

 

[Nhoro]

Peregrine has 8.5 mm Meplat so about 70 % in 458 caliber and 500 gr.

 

[Dewald]

Good morning Dewald.

I thought I had tested some of these back in the days, but can't find anything on them. Tested Rhino and Peregrine here, and I was sure Dzombo, but can't find photos of them, and I may have had some and never got around to them. I will continue to look for that.

The measure of any solid and how it may perform, go to Factors #1 and #2 and review. For a Flat Nose Solid to be terminally stable it needs to have a 65% Meplat of Caliber. Meaning you can shoot a 65% Meplat in a smooth bore, and it will be terminally stable for 90% of its terminal penetration. Less meplat, and it will not, you will require other factors to come into play to keep the bullet stable enough once it starts terminal penetration to accomplish the mission required of it. Nose Profile #2 is very important as well.

Dzumbos appear to be basically a Round Nose that is flattened off on the top. This is not a bad nose profile, and very much like many of the first FN Solids, Barnes followed this as basically did Hornady. The Dzumbo looks to be a little shy on meplat size for optimum stability. However, keep in mind that under most circumstances even less than perfect bullets can remain stable long enough to accomplish the job required of it. In all the test medium we are working with a solid consistent mass, always aqueous. Taking bone out of the equation for now, and considering only comparison from aqueous test medium to animal tissue, one will get 35% more penetration with Animal Tissue than the test medium. This is a basic rule of thumb, and can be slightly more, or slightly less depending on variables involved in the particular path of any given solid. This penetration rule of thumb is different with expanding or trauma inflicting bullets, but basically count 35% more for solids.

I have no doubt that the Dzumbo would do well in the field. In my opinion it could be better with a larger meplat. The RN Cut off to a Flat Nose is a good design, it is a strong nose profile, possibly stronger than most others. But it is not the optimum nose profile for depth of penetration. Other nose profiles are better in that Factor. Again, not kicking this bullet. I used a lot of the Barnes FN when they came out and found them superb. Barnes were at 65% meplat.

This Rhino seems to be close in design........ But mind you, small tweaks in these solids, ones that require measurement to be known can make a big difference.. So appearances can mean nothing with a solid. And keep in mind, 58" of straight line penetration is more than enough to accomplish any mission asked of a solid in 90% of all cases.

Thank you for the response Michael, I appreciate it.

 

[Major Khan]

When I used to work as a branch supervisor for the Bangladesh Ordinance Factories from 1982 to 1988 ... I used to ( Among other things ) supervise the manufacture of .303 British calibre cartridges , which would be issued to our forest department officers ( For their department issue Lee Enfield service bolt rifles ) . We used to manufacture a solid metal covered round nose 215 grain bullet ... Which used to be loaded in to cartridges , meant for dispatching rogue Asiatic elephants . Our 1st batches were copper " Jacketed " , lead cored and had rounded noses . Our forest department officers reported unsatisfactory penetration for frontal brain shots on the large elephant bulls . In 1987 ... We shifted to a thick steel " Jacket " and a slightly flattened point . These perform far better on the large elephant bulls ( Even when frontal brain shots are made ) .

I have the file with me , and I could translate it from Bengali to English ... Should anyone be interested in the research , which was conducted .

 

[michael458]

Peregrine has 8.5 mm Meplat so about 70 % in 458 caliber and 500 gr.

Indeed good news. The ones I tested in 2015 were 52% Meplat, and as stated in my report back to Peregrine that an increase in meplat size was required to make the bullet more stable. I never heard anything back, but seems they paid attention, or increased the meplat size regardless, either way, its a plus for their solids.

While not the subject of this thread, I was extremely impressed with their expanding bullet, it was superb, and along the same lines that John from North Fork and I worked on with the .500 caliber Expanding CPS (Cup Point Solids).......This is an extreme bullet for inflicting trauma. Deep penetration! But that is for another day and another thread................

In 1987 ... We shifted to a thick steel " Jacket " and a slightly flattened point . These perform far better on the large elephant bulls ( Even when frontal brain shots are made ) .

Excellent. Probably around 2007-2008 I found some similar results with two other semi flat Round Nose FMJ from Woodleigh, that gave some extreme performance, unlike any other typical RN FMJ, or even semi RN FMJ. One was a 320 gr Woodleigh 9.3 caliber FMJ and the other was a 310 gr .358 caliber FMJ. Both of these bullets would give extreme deep straight penetration before going unstable, always 60+ inches dead straight before veering off course. However, Woodleigh had another 286 gr FMJ in 9.3 caliber that was not worth a damn for straight line penetration and it looked to be exactly the same as the 320 version...... the 286 would loose stability at 26-30 inches of penetration and even start tumbling......

Barnes had a 250 so called FN for 9.3. The meplat size was 48%, at the time Barnes said they went with the smaller meplat so they could feed/function in CZ rifles. This really pissed me off, as the bullet was one of the worst solids I had ever tested. At 16-17 inches it would tumble sideways and go to anyones guess...... I am not a fan of lowering performance of a bullet just so it feeds in a particular make of rifle. Either Fix the damn rifle, or get rid of it and get one that will feed and function with proper bullets.

 

[michael458]

In the beginning I had CEB make some of these bullets in 9.3, which did very well, more or less similar to a Barnes FN........

And then of course later after discovering the #13 Nose Profile we went with this one for 9.3 caliber................

Another topic, for another thread someday could be the Bands that are used on the current bullets, but like the NonConventional Trauma inflicting bullets, another topic, for another thread on another day.........