Home Forums Hunting & Shooting Ask The Gunwriters Fresh Evaluation of the "Copper Bullets"...

I thought I "herd" ARs were morer deadlier....dammed automatic rifles anyway. That must be why!!!

might it not be interesting then, considering the results with different twists at different velocities to see what happens using the identical bullet and velocity but different twist rates. perhaps this has been mentioned but i missed it.

Copper flows under the pressure created by impact, not as much as lead but it still flows, otherwise it would not expand.

And I would expect its expansion to be influenced by the spinning rate, probably not as much as with a cup and core projectile, which does happen, but I can�t see why it would not be affected.

It would be an interesting test... Hopefully, with so many short and long twists rifles in .224 calibers around, someone will find the time and take the trouble.

Alvaro

John,

I am strictly talking about monos. I have no queston about lead spinning very fast is capable of a lot more splatter because it tends to come undone in even small targets. You probably couldn't measure a difference in expansion with calipers on bullet in that case.

Monos are tough enough that if you could recover enough of them you might be able to measure something. According to Barnes you can't make them come undone in the air no matter how fast you spin them, and I think that part of their answer is true. I don't know that we couldn't make the same statement about heavier constructed lead core bullets too. Anyone with a fast twist barrel has to take some light construction bullets and wind them up just to make them go poof.

I remain doubtful that spin rate will do much for expansion with monos while I believe that enough RPMs can make a noticeable change in tissue damage. I can see the forces would try to make it happen, but monos are pretty tough to bend or open more if you try to work on a partially expanded bullets. Fully expanded monos probably cannot be expanded more short of hitting steel or something close to that resistance.

It can't help them open "more" because there are physical limitations to how much frontal area a mono is capable of.As you say,you can't spin the apart,and no one is saying that.... they can only expand so much...but it might help them open AT ALL...and especially as distance increases, and velocity falls off.

And of course there is a difference in how much expansion you will get as distances stretch,and velocity declines....sure they tell us that the bullets are designed to expand down to 1800-2000 fps,but they don't say "how much"..and the faster twist can be a factor in facilitating expansion as distance increases.

With any tough,expanding hunting bullets,velocity and faster rpm's go hand in hand in getting desired results.

There is no such thing as centrifugal force.

Miles,

You keep wandering off point, or misunderstanding my points.

First, I mentioned the Barnes statement on jacketed bullets because it showed whoever "answered" your question didn't know what they were talking about on that point. And if they didn't know the correct answer to that, how do you expect them to know the correct answer to your question?

Next, Alvaro's ("BBerg") orginal question was: "John,
Which one will expand to a wider frontal area at the lowest velocity?"

My answer was that probably one of the all-copper bullets would be most likely to open at lower velocities, since copper is softer than gilding metal. But I also qualified the answer by saying it would also depend on initial velocity and twist rate.

I should also have qualified it by saying different monos are designed to open up more or less widely. As an example, when I first tested Nosler E-Tips in media against TSX's, the E-Tips opened wider and hence didn't penetrate quite as deeply. (Both were 180 .30's from the same .300 Winchester Magnum, using the same load.) This was because the E-Tips had a deeper hollow point, so more of their nose peeled back, making a wider mushroom.

ALL the mono bullets have a maximum diameter they'll open to, almost (but not quite) regardless of impact velocity and rifling twist. (The exception is when they lose petals.) Alvaro's question was not about individual monolithic bullets opening wider, but WHICH MODEL would open wider at lower impact velocities. This is a highly relevant question, since anybody who's used mono's at longer ranges has seen some fail to open--or if not totally fail, not open up completely. And the examples are far more common than with lead-cored bullets.

NOBODY ON THIS THREAD HAS MENTIONED MONOLITHICS COMING APART IN THE AIR--EXCEPT YOU! That was not a point of discussion, and is irrelevant to the conversation.

Also, nobody else on this thread has insisted that monolithic expanding bullets somehow bypass simple physics.

dt: Whatever. You want the correct terminology, go ask an engineer.

Here's a totally off the wall thought from my feeble mind.

What if a higher twist rate results in the bullet having more contact with the material it impacts?

Here's the logic behind it. If you have a zero twist rate the path of the bullet is a straight line. If the bullet spirals it's a longer path through whatever it comes in contact with. The higher value of kinetic energy is what carries penetration forward but the spin effect increases the area of contact by spiraling.

Here's a way to imagine it. If you poke your finger against a desk the area of contact is limited. If your finger twists slightly before stopping the amount of contact is increased.

Increased contact = more expansion

I'm not an engineer so I could be totally wrong and I'm OK with that.

Whatever???? How about let's just keep it simple and call it "perpendicular axial momentum"? ? ?? Us rifle loonies.......er, unapologetic rifle aficionados (I had to google that ) can't not be getting our gack (I don't know a correct term for that - perhaps "Dobrenski's minutia"? ) right!

Klik: I'm worn out...

If no one wants to believe an Internet goof-ball like me,they should at the very least be able to get their thoughts behind Mule Deer on the issue,who has tremendous credibility and is saying pretty much the same things.

Explaining the gack will kill you!

Bob, There are several reasons why you don't often find me arguing with either you or John. The fact that my experience doesn't leave much basis on which to form an argument isn't even at the top of the list. A lot of times it's actually fun to see if I can flush one or both of you out just to get things said in a way that makes more sense than what I am able to say.

Does anyone remember an oddball chambering from many years ago that I think was called the 257 Condor? Could have that wrong.

I seem to remember the inventor claimed super duper fast spin rate caused the bullet to do spectacular things when it struck game.

I don't remember much more than that but someone else might. I think I might have read it in one of those old GUNS back issues you can download.

John, I'll admit to only using Barnes TSX and TTSXs of all the monoliths so far but in a bunch of cartridges ranging from 7mm to 375. In regard to the TTSXs, I've had good accuracy but have experienced about 6 % per box of fifty--at least three--of lost "Ts or Tips" across the spectrim of calibers. They then become TSXs with larger hollow points.

Anybody else see this or am I off the curve?

George,

I haven't encountered that, but have probably only opened 20-25 boxes of tipped mono bullets.

a little bit oof suject, but now that you mentioned TTSXs without the tip let me tell you, out of curiosity, my experience last week at the range.

with the roebuck season opening tomorrow, I went to the range with my K95 kipplaufcuhse and its 22-250, 1:14" barrel and the load I will be using this year, Sierra SMP 63gr, Norma's URP and CCI BR-2.

everything worked out as usual and the rifle printed a 5 shot group of barely one inch at 100 meters.

later into the season there are a couple of areas where we are allowed to shoot wild boar before they start feeding in the wheatfields and sunflower fields to prevent them from making damage, so I always like to carry a couple of cartridges loaded with Barnes bullets and because the 55gr TTSX look so well (!) and because they shot so well in my 1:9.8" twist 5.6x57 I decided to give them a try.

loaded with Norma 203B and the same BR-2 primer I took three shots, two of them hitting like 10" appart, and the third not even hitting the paper!

so I took the tips off the next three cartridges, shot them and printed a nice 0.7" perfect triangle!

it made such a huge difference that none of us at the range would have expected anything like that!

rgds.,

Wow.......a couple of days ago I was just wondering if these bullets would work well in my .308 and would be good for black bear, after reading the discussion don't i feel simple now!

Yeah, see what you started....Lol

Your 308 will work fine on your Black Bear. You just need to hit them in the right spot.

Wish you luck on your hunting trip.

Steehead is spot on!
Rotation cold and humidity all effect stabilization. A marginally stabilized mono can bend the nose over causing no expansion. More rotation equals greater centrifugal forces to pull the petals outward. This is basic logic IMHO

Yep, extra zip and spin are certainly among the reasons reasons for light TSX's killing so well.