Not to hijack this thread.

quote:

Alf posted: High speed photography of a varied assortment of currently available monometal HP's and expanders have shown that all, without exception turn in target after the shedding of the petals and in most the actual expansion and shedding of the forepart happens almost directly after impact.

Alf,
Pity they did not include GSC HV bullets in this test. We have found no evidence that GSC HV and HP bullets routinely behave as you describe. On the contrary, GSC hollow point bullets shed petals at varying depths that are dependent on impact speed. Extremely high speed impacts will shed the petals earlier than lower speed impacts. It is only through a very narrow impact speed band, where shearing or not shearing is borderline, that all petals do not shear off.

After the petals have sheared off, only flat base bullets have a tendency to tumble. Boat tail monos such as the GSC HVs are dart and shoulder stabilised and, tumbling after or during the shedding of petals is unlikely and unusual.

Do you have a source for the info, I would be interested in seeing it.

Evening Gerard,

What about the HV's nose geometry makes it shoulder stabilized? I'm not seeing it in the HV or any other TO/SO HP. Given the irregular nose shape sans petals, I doubt significant stability is possible. Interesting your comment about increased stability with the boat tail configuration, this is something I commented on two years ago RE: the FN's. Do you have data to support this?

Regards

Hello Jay,

quote:

"What about the HV's nose geometry makes it shoulder stabilized?"

HVs are designed to be shoulder stabilised after shedding the petals. Neat, wouldn't you say? Even the little 40gr HV, which does not have much of a boat tail, winds up shoulder and dart stabilised. The result is reliability such as this.

Do we have data to support the boattail v flat base? Not any more, I did a lot of comparative shooting of flat base and boat tail monos around '96 / '97 and, once the principle was clear, I moved on. Our old HP range from '93 to '97 had some flat base designs but we have phased them out. I only do a flat base if there is no choice or if the center of gravity must be manipulated rearwards.

hi Gerard
do you have any general agent in scandinavia? it seems the lead core bullets are going to be banned in future . i like your lineof bullets .
cheers
yes

yes,
Contact Andre Flor, he will be happy to help.

thank you gerard.
the greatest virtue of monolitic bullets is to not contaminate the meat like lead core bullets do.
best regards

quote:

Originally posted by Gerard:
Not to hijack this thread.

Pity they did not include GSC HV bullets in this test.

Gerard,

I understand that Michael458 has received some GSC .416 caliber 410gr FN bullets for testing from another AR member but has been under the weather this week. I imagine that you’ll see the test results sometime next week.

quote:

Michael458's sadly do not show or emulate the tumbling behaviour of solid oblong projectiles in dense media and therefore are not valid simulations.

Top of the Morning Gents!

Alf

Well different media does without doubt show different reactions and bullet behavior. However, you are incorrect that my test media does not show tumbling behavior of many various different solid oblong projectiles, it most certainly does. Of course there are many projectiles I can show that tumbled or veered off course within one type of bullet, or nose profile. But here I think we are discussing the NONCON bullets in which consist of a bullet, mostly HPs that shed or shear petals during penetration. I am working fairly extensively with these right now in three different calibers, and several different rifles. First .500 caliber--458 Caliber--416 caliber.

I know that you disagree, and that is fine, but at this moment, with the different bullets I have tested to date I am convinced, until I can prove it incorrect myself, that the one stability issue that I have with a 330 gr 416 caliber brass NONCON is directly related to 1:14 twist rates on my current 416 B&M rifles. I also suspect it is possible for it to be "caliber" related, but currently I fall upon twist rate. With this particular bullet it remains dead straight for 90% of it's total penetration, it tumbles after losing stability after that. This is only 2 inches of penetration, at the very end.

So far, in prior tests of the few 458 caliber NONCONs I have tested do not exhibit this at all. This has been only a couple of examples of a 428 gr NONCON and a 305 gr NONCON in 458 caliber. This was over a year ago for these. I am working on getting some more samples in 458 and will be testing this week a 260 gr and more 305 gr bullets, waiting on the larger ones to come in.

I have tested EXTENSIVELY .500 caliber brass and copper NONCONs, these rifles larger caliber and 1:12 twist rates. The following bullets have been tested:

320 gr Copper HP
350 gr Brass HP
380 gr Copper HP
426 gr Copper HP
470 gr Copper HP

Several tests have been done with these bullets, in fact multiple tests in several different rifles in 4 different cartridges at various velocities, hi and lo. Tested in 50 B&M Super Short--50 B&M Long--50 B&M SA--and 500 MDM. All with 1:12 twists. This change was made from 1:18 twists of the original prototype guns because RN solids would not stabilize during terminal penetration. After the new twist the bullets were stable to 85-90% of their total penetration, and then tumble. Of course the solids with proper flat meplats are stable to 100% of there terminal penetration.

Now to continue the story concerning the 500 caliber NONCONs, NOT ONE BULLET has ever tumbled or veered off course and all were found at the end of penetration nose forward. Recently an excellent idea was presented by RIP--the famous Ron Berry, to insert "witness cards" into my mix. These cards have been inserted at intervals of 4 inches with the NONCONs, in each case one can easily see when straight line penetration occurs or does not occur and have a permanent record of the test.

Now I don't have a horse in this race, and it seems the concern is tumble or not tumble. I don't like tumbling because it presents a quality that cannot be controlled, at least a variable that I would just as soon not deal with. Now if my 416 caliber bullet is 100% stable to 90% of it's penetration, then I am not overly concerned with that. It does this at low and hi velocity, and is repeatable. NONE of the .500 caliber bullets have ever veered off course or tumbled! None of the tested 458 caliber bullets have tumbled. So this is why I contend that it is related to either caliber, or twist rates, I will learn this soon for fact.

I contend that it may be the "translucent synthetic ballistic gel" that does not exhibit or emulate proper behavior of bullets, and therefore is not a valid simulation. There are far too many variables to consider to make a blanket statement that all NONCON bullets either tumble or they don't? That is a ridiculous statement, that is obviously not correct. Different test medium will react differently too. I have dug too many bullets from actual animal flesh and from my test medium, I know very damn well what is represented, by both! Ballistic gel makes for real nice photos of bullets, great for bullet manufacturer advertisements, and so forth. Nahh, I will stand behind my tests as being an excellent medium in which to test, and does emulate very well what will go on in the field, where it counts the most!

If it tumbles in my test medium--it stands a damn good chance of doing the same in the field on animal flesh. If it penetrates dead straight in my test medium--I know damn well it will penetrate dead straight in animal tissue. If it shears petals and continues in a straight path in the test medium--it does so in animal flesh and does on buffalo. End of Story!

Michael

I also want to add, I have no interest in pointy 30 caliber FMJ bullets, or things such as that. The purpose of said bullets regardless of what they do, they will accomplish the mission assigned to them in the arena they are meant to be used. Bullets I test and have an interest in are bullets that I am asking a specific mission of, to shoot and kill buffalo or elephant, or antelope or what have you. I don't care what military FMJs do, they are for other purposes and have a small easy mission to accomplish. I have never worried with testing these, and see no reason for me to do so, since such won't be used for any mission I might embark upon. The same reason I don't test much deer bullets.

Can someone tell me how much penetration one needs in "ballistic gel" to be 100% sure of getting enough penetration to be reliable on buffalo? Hippo? Elephant? Lion? Bear? Eland? Kudu? Elk? Moose? Number of inches of "ballistic gel", to be able to accomplish these missions? If you want these numbers from my test medium, I have them, I can give them to you! And they will work every time!

Michael

Alf,

I’ve followed your many posts on the various forum threads relative to the issue of bullet tumbling within the body cavity of the hunted game, especially in Michaels various threads regarding his test results.

I’ll admit right up front my personal testing experience is limited to assuring rifle is appropriately sighted with ammunition appropriate to the live animal shootee and then was the shootee appropriately killed. Appropriately killed is either DRT or no more than a short run and a single follow up shot otherwise not appropriately killed and quick perusal to determine if failure was lousy shooting on my part or failure of bullet to do its job.

I do have practical testing experience with .38 Special, .357 Magnum, 40 S&W, and 45 ACP cartridges for both accuracy and bullet performance…though you’d disagree with the test media for bullet performance as the test media varied from various automotive vehicles and construction materials comparable to doors, walls, etc. The testing was relating to the armory of the federal agency that I worked 35½ years for before retirement and the testing was to assure that the revolver and later semi-auto cartridges that I and (at the time) the 3+K gun carriers in our agency could kill or seriously injure the live animals that we periodically needed to shoot even after the need to penetrate doors, walls, or various parts of motor vehicles. And yes I assisted in performing similar tests with rifle and shotgun.

However I’m only a recent reloader of centerfire rifle cartridges totally without the experience of Gerard or Michael hence my interest in the ‘actual’ performance of monometal bullet performance in both test media and live animals from those who do have the experience.

As far as all bullets having the inherent tendency to tumble within the live animal shootee post impact, I’ve read many practical studies of bullet design and performance relating to the US and British militaries.

And if all bullets inherently tumble within after impacting the live animal why did the British military spend many months and years in bullet design testing to finally identify the exact shape and bullet composition for a FMJ spitzer bullet for use in the .303 Enfield that would both fly straight for many hundreds of yards to the intended live animal target and then successfully tumble within the live animal target post impact? It seems that the greatest difficulty that they had in the bullet design was overcoming the inherent tendency of the FMJ spitzer bullets to fly straight to the live animal target and then fly straight through the live animal target without tumbling.

Michael has tested the SST HP and FN bullets that he uses in his various B&M and MBM cartridges and has shared the photographs of the results in both his bullet trap in his laboratory as well as in elephant and buffalo, most recently his buffalo hunt in Australia. Michael has stated that his live animal and laboratory testing indicates that it is abnormal for the SST HP or FN monometal bullets to tumble.

Gerard has stated that his company testing indicates that it is abnormal for his GSC HV (hollow point) or FN monometal bullets to tumble.

Do you have any personal experience conducting extensive testing HP and FN monometal bullets in test media or live animal? Or is your experience limited to citing academic studies that indicate that all bullets tumble when within live animals?

If you do have extensive personal experience in testing HP and FN monometal bullets in both live animals and test media…please share the actual results of your practical tests so that the reader can absorb the extent of your efforts as well as draw their personal conclusions from the experience. Believe me it would be much more rewarding for all participants.

Thanks,