Copperhead 184gr VLD

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ben_g
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Joined: Sun Apr 24, 2016 7:37 pm

Copperhead 184gr VLD

#1 Postby ben_g » Sat Dec 15, 2018 8:44 pm

With the latest small shipment of Berger’s bought in by BRT seeing 7mm pills now up to 90c ea my next order will likely be for Kens new 184gr bullet.

Has anyone tried any yet? Had anyone got a pic of one side by side with a Berger hybrid or VLD

Cheers
Ben.

willow
Posts: 209
Joined: Sat Aug 15, 2015 9:51 pm

Re: Copperhead 184gr VLD

#2 Postby willow » Sun Dec 16, 2018 5:08 pm

ben_g wrote:With the latest small shipment of Berger’s bought in by BRT seeing 7mm pills now up to 90c ea my next order will likely be for Kens new 184gr bullet.

Has anyone tried any yet? Had anyone got a pic of one side by side with a Berger hybrid or VLD

Cheers
Ben.


Haven't tried any. I did speak to Ken about it, trying to ascertain what type of design he went with and he told me it is a VLD design as opposed to a hybrid like the new Berger pill. I don't know if anyone has tested the bullet though. I couldn't get the famed 103gr 6mm pills to shoot so I'm reluctant to drop the coin on these until I hear of some success stories.

AlexE
Posts: 112
Joined: Fri Feb 16, 2018 9:18 am

Re: Copperhead 184gr VLD

#3 Postby AlexE » Sun Dec 16, 2018 8:53 pm

I've pestered Ken a few times about these. Last contact (10 days ago or so) he advised that he still didn't have any and did know when he would. Something to do with getting the jackets. As soon as they're available I'll give them a go.

ben_g
Posts: 137
Joined: Sun Apr 24, 2016 7:37 pm

Re: Copperhead 184gr VLD

#4 Postby ben_g » Sun Dec 16, 2018 9:17 pm

Thanks guys. Hope he gets some going soon, I’m keen to try.

Happy to hear they are VLD design, I have found the Berger 180VLD’s very easy to get working and that’s what I have been using in my 284’s. Just jam 0.015 and away you go, also found the same thing with 130gr 6.5mm Berger VLD’s, hopefully Kens bullets will be similar.

I like the Berger VLD’s so much I could possibly be convinced to swap my incoming batch of Hybrids for some......

williada
Posts: 799
Joined: Wed Jul 22, 2009 12:37 am

Re: Copperhead 184gr VLD

#5 Postby williada » Mon Dec 17, 2018 10:26 am

My preference would be for the hybrid design. In a competition over a few days the likelihood of hitting rough weather and if mounds or terrain are uneven you can be in trouble with VLD"S which want to respond more to changes in air flow and pressure points in the air mass particularly over steep mounds e.g. Bendigo. VLD's can be very "twichy" which leads to instability at long range and out weighs the reduced drag from the base to maintain velocity and BC. Faster twist rates required add a little to bore wear but find weaknesses in projectile jackets where a good shoot can be undone by one shot where there is a jacket weakness. But VLD's, if all made well, perform best in ideal conditions. I hear Ken's quality is first class, so the fear of a poor jacket is mitigated.

bruce moulds
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Re: Copperhead 184gr VLD

#6 Postby bruce moulds » Mon Dec 17, 2018 4:29 pm

"pressure points in the air mass"?
bruce.
"SUCH IS LIFE" Edward Kelly 11 nov 1880
http://youtu.be/YRaRCCZjdTM

Ken Melgaard
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Location: West Wodonga, Vic

Re: Copperhead 184gr VLD

#7 Postby Ken Melgaard » Mon Dec 17, 2018 5:21 pm

Re Copperhead Bullets 7mm 184 grain VLD Bullets
Yes, l hope to have some good news very soon, as l will have what l need to make them in the first couple of weeks into new year, so to all those that have contacted me regarding samples, l will send them out as soon as l am happy with the Bullets.
I appreciate your patience as it has been difficult past 12 months to get the jackets and bullet forming dies.
So.... hopefully 2019 is a better year with regards to getting jackets.
Merry Christmas to all and make all X for 2019

williada
Posts: 799
Joined: Wed Jul 22, 2009 12:37 am

Re: Copperhead 184gr VLD

#8 Postby williada » Mon Dec 17, 2018 10:44 pm

Bruce, wind flowing over and around objects causes pressure changes around the object. The object causes wind friction. The pressure point is the narrowing of the pressure gradients like over the top of a mound. When the wind blows hard it becomes a problem with the bullet nose trying to re-orient to the direction of the wind flow which it will always do. Check the web for "How Bullets Fly". VLD's are longer and subject to more leverage hence they are known to be "twitchy" in turbulent air. On the lee side of the mounds there are low pressure gradients. Bullets with greater radial torque i.e. larger diameter, are more resistant to being knocked offline. Hence I would would prefer 7 mm over 6 mm as an all rounder and a hybrid. In really rough conditions, maybe .308 and a tangent ogive pill. Try this link: https://kidsgeo.com/geography-for-kids/ ... on-effect/ :)

bruce moulds
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Re: Copperhead 184gr VLD

#9 Postby bruce moulds » Tue Dec 18, 2018 5:52 am

thank you williada.
sounds like keeping the twist rate up might help here.
bruce.
"SUCH IS LIFE" Edward Kelly 11 nov 1880

http://youtu.be/YRaRCCZjdTM

ben_g
Posts: 137
Joined: Sun Apr 24, 2016 7:37 pm

Re: Copperhead 184gr VLD

#10 Postby ben_g » Tue Dec 18, 2018 6:45 am

I am not quite following your logic Williada.

Are you saying it’s the overall length, ogive shape or the length of the nose in front of the ogive that lends a VLD to be more sensitive than a hybrid.

I do not have any 7mm Hybrids to hand at the moment, however I do have 6mm VLD and hydrids to compare, the 105gr hybrid is longer, has a shorter bearing surface and appears to have a longer nose in front of the ogive, shouldn’t it be more susceptible if what you are saying is correct?

I thought BC is the main determinate of a bullets resistance to cross winds and drafts pressure changes ect?

I look forward to receiving my new batch of Hybrids and hope I can make them shoot as well as the VLD’s.

http://ffden-2.phys.uaf.edu/212fall2001 ... _stability
I have found this link on the web, is this the one you mean? I’ll have to sit down in a quiet moment and give it a good read.

I’m also interested about the larger caliber being more stable through bumpy air, I don’t yet have a magnum cartridge and have been seriously considering building a 30cal to utilise the 230gr Hybrid pill for long range F-class at the match rifle events, however on paper calcs alone a 7mm SAUM will easily keep up with the 30cal as far as wind drift goes, interested to hear if the big 30cal has an advantage in rough bumpy conditions.

williada
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Re: Copperhead 184gr VLD

#11 Postby williada » Tue Dec 18, 2018 11:05 am

Yep Bruce, but there is always some trade off to make depending upon the shooting environment.

Ben VLD's are more sensitive. I am generalizing, but to see the extreme, the comparison has been made between VLD’s and tangent ogives. The hybrids are in between.
VLD’s require higher twist rates to stabilize them. The nose of the VLD is longer to balance the centre of pressure with the centre of gravity of the projectile to prevent it tumbling end over end.

In any projectile if the body is short, in-bore yaw becomes a problem and that is controlled by a better match between throat diameter and bullet diameter. The object is to line the projectile concentrically with the bore. People commonly jam the VLD to achieve the same outcome.

The twist rate is usually determined by the major factor of bullet length. That has a big influence also on rotational inertia and VLD’s are commonly longer. There have been a number of improvements in stability formula’s starting with Greenhill’s. Millar came on the scene and gave us that optimum figure of 1.5. However not all his studies were revealed? The fact that his partner pushed the effect of the hollow nose on optimum twist rates led to the development of pointed bullets to improve BC. BC is linked of course to form factor and bullet length. Then you have Mc Coy’s embodied in the JBM program and further advanced stuff in PRODAS (military) all of which are modifications to gyroscopic stability.

BC actually decays as does velocity over long distance and I believe the Millar calculations were muzzle based calculations therefore linear based. Litz’s calculations by his point of mass model demonstrate that BC decays if bullet if Sg is less than 1.3. It is a model based on 3 degrees of freedom. That means other factors are held constant or omitted for simplicity of explanation. My interest is long range where the nose orientation is critical to drag with the angle of attack in terms of the nutation of the projectile. The calculation is significant, to find a new optimum twist rate for long range but it is hair splitting for short and mid ranges. Short and mid range is where the market lies and as such there has been little interest in long and extreme range shooting.

Litz’s model relies on the underlying characteristics of the bullet which are not accounted for in a linear approach and overestimate spin drift. If a bullet has to travel further via a detour this effects it time of flight. This of course varies directly with the bullet’s potential ballistic drag force which is greatly influenced by nose orientation. That means the spin drift of the bullet is directly proportional to its yaw of repose angle. Spin drift is directly proportional to the small yaw coefficient of lift which VLD bullets reduce at supersonic speeds and relates to nutation.

But all bullets, and my major point has been, that atmospheric density varies with shooting conditions i.e. over high mounds or objects which alter this density on an interactive micro/macro scale. There is no doubt in my mind that in best conditions the faster low drag bullets will perform the best for long range shooting. Ideal conditions are not always present and the hybrid is a true compromise.

I have always advocated that tight groups at short range can be misleading and not necessarily applicable to long range performance if the velocity is not up there and how this is also connected to barrel flip and different group axis’s as I submitted with a nodal pyramid test Ecomeat did for me some years ago. It is my view, that guys playing with minor twist rate adjustments would be better served adjusting velocity, except to say the energy limits on some ranges can make this difficult in extreme cases.

It is also true that spin drift is inversely proportional to bullet weight. For diagnostic ease, spin drift is also proportional to bullet drop. People have not concentrated enough on the importance of spin drift and the trade off and rotational inertia and the trade-off at times with radial torque and bullet shape. The optimum application is specific to where you shoot and the conditions found.

Now Ken has mentioned the importance of jackets. They are critical. Any bullet resulting from imbalance to variable wall thickness core fixing or void or hardness is best controlled by slower twist rates. On the other hand look at the section on tractability to see the effect of projectiles being over spun. It is hard to keep this stuff simple. Reading “How Bullets Fly” is a good introduction. Ben I hope I have explained well enough for you, but these days I prefer not to get into long discussions and would like to think anything said inspires investigation. It’s a journey. Almost forgot, yep convinced 30 cal better in the bump due to greater radial torque. Case in point was top FTR score over the 7 SAUM at Gippsland Prize meeting in difficult conditions at 1000 yards recently. Once the direction of a projectile is changed there is no magic to bring it back. Prevention is the cure.

ben_g
Posts: 137
Joined: Sun Apr 24, 2016 7:37 pm

Re: Copperhead 184gr VLD

#12 Postby ben_g » Tue Dec 18, 2018 11:54 am

Okay, I am following you, and as I said I only have 6mm on hand to compare, but I’m pretty sure from pics the 7mm hybrid is also longer in forward of its bearing surface than the VLD. Manufacturers can create long or short secant ogives.

I have been following the US shooting forums to see if anyone is having good success with the new Sierra bullets (150gr 6.5mm and 110gr 6mm). While some shooters are reporting success it appears that many are finding them inconsistent at long range. Could it be that Sierra have pushed the length of the nose section too far? Also the twists required to stabilise them can result in jacket failures at velocities required to make them competitive with 7mm magnums.

On paper the 150gr 6.5mm in a 6.5x284 pushed around 3000fps should be very handy, but the reality is US shooters who have tried them are struggling to make them work. They do seem to work in slower 6.5mm calibres without jacket failures but for f-class this offers no advantage to 7mm

Anyway, regarding Kens bullets, having seen and used his 6.5mm and 6mm designs they don’t usually have an aggressively long nose. Having a consistent, high quality Aussie made option is going to be great. I look forward to trying some.

williada
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Joined: Wed Jul 22, 2009 12:37 am

Re: Copperhead 184gr VLD

#13 Postby williada » Tue Dec 18, 2018 2:45 pm

Yes Ben, we are all looking forward to Ken's projectiles because we are sick of being ripped off. So called supply issues are manipulated when we consider copper and lead are at world lowest prices. Suppose a price increase will be rationalised by suppliers that inputs of raw materials have risen. Pity we don't make jackets in this country. Bear in mind that bullet shape determines where gyroscopic stability rests because of the requirement to balance centre of pressure and gravity. It is easier to adjust length to satisfy that balance. So it doesn't matter really if the hybrid is longer in a larger bore size, that is to be expected, because it depends on its shape and weight when optimizing drag. I mentioned previously, "in any projectile if the body is short...", that also includes secant ogives. The added advantage of the hybrid is that it goes further to addressing the in-bore yaw issue as the lesser of two evils and sits in the lands closer to an optimum lead angle which is ideally should be tangent to the ogive. This also gives greater flexibility in adjusting loads by seating depth to play with peak pressures and bullet exit timing to assist positive compensation which only long range shooters may consider. The US shooters are generally subject to distinct seasonal changes and in each season the environment is more stable than Australia. Unfortunately, we keep looking towards the US for inspiration and the holy grail, but the real talent also lies in our backyard. Look what DaveMc and the boys achieved followed up by Craig. Australians should dump the cultural cringe and reflected glory. Would just love to see Aussie with Ken go all the way. I wish you every success and a great Xmas.

Ken Melgaard
Posts: 67
Joined: Fri Jul 01, 2005 7:32 pm
Location: West Wodonga, Vic

Re: Copperhead 184gr VLD

#14 Postby Ken Melgaard » Fri Jan 25, 2019 6:58 pm

Re 183-184 grain VLD Copperhead Bullets
At long last have finished some of the 7mm 183 grain VLD Bullets and will contact those that have emailed requesting Bullets to test
So will be looking forward the results from testing these new Bullets
Good Shooting to all in 2019

ben_g
Posts: 137
Joined: Sun Apr 24, 2016 7:37 pm

Re: Copperhead 184gr VLD

#15 Postby ben_g » Tue Feb 05, 2019 8:33 pm

Received my sample pack of 183gr VLD copperheads from Ken.

Thanks Ken!!

Quick measurements

Berger VLD hunting
OAL= 1.514
BTO= 0.758

Berger Hybrid
OAL = 1.523
BTO = 0.717

Copper head VLD
OAL = 1.585
BTO = 0.668

Picture from Left to Right is Berger VLD, Hybrid, Copperhead.

The meplats on the copperheads are much cleaner and more uniform than those on my Berger’s. Really looking forward to running these in my 8.5twist 284. I hope it’s fast enough twist.

The G1 BC claim on the box is 0.690, they certainly are a long bullet with a long ogive!!
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