375/408 Banded Solids Test
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noel carlson
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"Not that it matters but I do have samples of every single prototype tested."...
Ah, but it does matter.
Kiwi Greg is a serious shooter: [ame=http://youtu.be/4XVNwrTaqo4]2065 yards 425gr CEB & 414gr GSC - YouTube[/ame]
"... the barrel has been in a corner at my house... "
Greg has been using his ZA specified gain-function 5R Bartlein successfully with both the 425 grain CE, and the 414 grain GSC. I am pretty sure he was seeking something more than ambiguous folk wisdom from your response. I presume Sling is also fairly insightful given his apparent appreciation of Frank Galli's test result indicating a .5 mil impact elevation increase at 1,000 yards with equivalent projectile mass, and muzzle velocities in two different generation ZAs. He did, after all, revive this thread after a very long time interval.
An appropriate reply would have been something like; "I have not been party to any prototype testing for almost four years... ". You did not even need to explain why this is the case, and left it at that.
Ah, but it does matter.
Kiwi Greg is a serious shooter: [ame=http://youtu.be/4XVNwrTaqo4]2065 yards 425gr CEB & 414gr GSC - YouTube[/ame]
"... the barrel has been in a corner at my house... "
Greg has been using his ZA specified gain-function 5R Bartlein successfully with both the 425 grain CE, and the 414 grain GSC. I am pretty sure he was seeking something more than ambiguous folk wisdom from your response. I presume Sling is also fairly insightful given his apparent appreciation of Frank Galli's test result indicating a .5 mil impact elevation increase at 1,000 yards with equivalent projectile mass, and muzzle velocities in two different generation ZAs. He did, after all, revive this thread after a very long time interval.
An appropriate reply would have been something like; "I have not been party to any prototype testing for almost four years... ". You did not even need to explain why this is the case, and left it at that.
Kiwi Greg
Well-Known Member
I'm still surprised how poor the 414 BC ended up being at 2000+
I haven't shot them at 1000-1500, I have a few left, maybe I should have a play & see what the BC is at that distance.
Comparing them to another proven projectile is the only way.
I haven't shot them at 1000-1500, I have a few left, maybe I should have a play & see what the BC is at that distance.
Comparing them to another proven projectile is the only way.
Oh my, where to begin. I'm totally confused by Noels last post. I made no mention of Kiwi Gregs barrel or his abilities to put it to good use. The barrel I was referring to is one first owned by a fellow in Las Vegas. It was a Bartlien 5.2/13ish, I bought this barrel,kept it for a while and resold it back to Jeff. Lowlight over on the Hide is using a similar barrel to test some of the latest inventions, I suspect this is the same barrel I had in my possession.
And now I ask, has anyone ever seen in print an explanation as to why I stopped testing bullets for Noel. If there is a printed explanation would someone find it and re-post it here. I have not and do not intend to tell the story of Terry and Noel unless future occurrences behooves me to do so.
And now I ask, has anyone ever seen in print an explanation as to why I stopped testing bullets for Noel. If there is a printed explanation would someone find it and re-post it here. I have not and do not intend to tell the story of Terry and Noel unless future occurrences behooves me to do so.
noel carlson
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"I have not and do not intend to tell the story of Terry and Noel unless future occurrences behooves me to do so."...
Prudent.
"The barrel I was referring to is one first owned by a fellow in Las Vegas."...
Yes, the same barrel configuration that Frank Galli is currently shooting, however; everybody on the inside knows 5R rifling is not optimal for banded projectiles in any gain-function.
Kiwi Greg,
"... maybe I should have a play & see what the BC is at that distance.
Comparing them to another proven projectile is the only way."...
I thought you did an extremely good job of documenting your field work. We should probably discuss the hurdles our State Department places in the way of shipping firearms related material to New Zealand. You will need another barrel for the ZA.
Prudent.
"The barrel I was referring to is one first owned by a fellow in Las Vegas."...
Yes, the same barrel configuration that Frank Galli is currently shooting, however; everybody on the inside knows 5R rifling is not optimal for banded projectiles in any gain-function.
Kiwi Greg,
"... maybe I should have a play & see what the BC is at that distance.
Comparing them to another proven projectile is the only way."...
I thought you did an extremely good job of documenting your field work. We should probably discuss the hurdles our State Department places in the way of shipping firearms related material to New Zealand. You will need another barrel for the ZA.
Kiwi Greg
Well-Known Member
Thanks Noel.
It isn't that hard to get them here, DED are bringing them in on a regular basis, wouldn't be that hard to get one shipped over with their ones.
I want everyone to know that I`m not affiliated with no one or no company that produces bullets, barrels,etc. I`m just interested in new, better designs. I am an avid extreme long range shooter (beyond 2000yds). I have shot IBS 600yd benchrest and currently an F-TR 1000yd shooter. I know Frank Galli owns Snipers Hide but I do not know the man. Since I have access to property that targets can be placed out to almost 2 miles, I am willing to test any bullet and/or barrel made using my money.
Thanks,
Sling
Thanks,
Sling
Rocky Mountain
Well-Known Member
Noel I'm interested in your point of view on why the extreme design high BC 375s seem to loose so much BC at 2000+ yards. I know CE tested and found this so stuck with what worked for them and the 414gr testing Greg did with my 375 DCM designed case?
noel carlson
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*Engraving-band drag*, to the tune of between five, and six, percent overall reduction in BC attributable to each band.
Rocky Mountain
Well-Known Member
Interesting but the CE only have one band and they still saw a rapid reduction in BC the more extreme the went with there design?
Rocky Mountain
Well-Known Member
How do you think your drive bands will compare to others on the market with the reduction of drag and BC at extreme range.
noel carlson
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Rocky Mountain,
The CE has an unusually long bearing surface, and a commensurately short nose utilizing a simple radius ogive. It is an extremely conservative design.
The ZA has a good BC from standard rifling due to multiple factors, but primarily in consequence to a low band count (four), of which the forward one is reduced drag (aerodynamic trick using micro-grooves). From a ZA barrel, the projectile will not have any band surfaces exposed to the oncoming airflow.
"How do you think your drive bands will compare to others on the market with the reduction of drag and BC at extreme range?"...
Nothing else on the market compares when the ZA barrel/projectile are used in combination with each other... not even close.
The CE has an unusually long bearing surface, and a commensurately short nose utilizing a simple radius ogive. It is an extremely conservative design.
The ZA has a good BC from standard rifling due to multiple factors, but primarily in consequence to a low band count (four), of which the forward one is reduced drag (aerodynamic trick using micro-grooves). From a ZA barrel, the projectile will not have any band surfaces exposed to the oncoming airflow.
"How do you think your drive bands will compare to others on the market with the reduction of drag and BC at extreme range?"...
Nothing else on the market compares when the ZA barrel/projectile are used in combination with each other... not even close.
MontanaRifleman
Well-Known Member
Maybe you are including the bore rider in front of the seal tite and driving band? CE bullets actually have very short bearing surfaces, if you do not include the bore rider. This does vary from bullet to bullet depending on where the seal tite band is placed.
On the 180 gr .308 C21's, the bearing surface, aft of the rear material displacement grove, is ~ .205. The driving band is ~ .095 if you wanted to include that as bearing surface, and the the seal tite band is another few thou. Call it .350 all added up. Not much bearing surface for a bullet that is 1.492" long.
noel carlson
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"Maybe you are including the bore rider in front... "...
Yes, I am. From an aero-ballistic standpoint there is no difference.
Ability to overcome wave-drag comes from ogive length (primarily), and ogive form (secondarily). There is no aerodynamic efficiency "credit" for a long projectile body, only potential "debits". Rifling engraving, engraving bands, pressure relief grooves, cannelures, etc. all contribute significantly to parasitic drag. You need to visualize a projectile shaft that has passed through rifling when estimating the drag penalty. At best, only smooth-surface drag will be present.
Mechanically, the bearing surface needs to be >1 1/2 calibers in length. Artillery shells typically have an ~2 caliber-long bearing surface. The practical requirements of mass on copper solids used in small arms is >2 calibers. The tail is between 1 caliber, and 1 1/2 calibers in length... as dictated by a boat-tail angle range between 7, and 9 degrees. The balance is left for nose length.
It is a balancing act.
Yes, I am. From an aero-ballistic standpoint there is no difference.
Ability to overcome wave-drag comes from ogive length (primarily), and ogive form (secondarily). There is no aerodynamic efficiency "credit" for a long projectile body, only potential "debits". Rifling engraving, engraving bands, pressure relief grooves, cannelures, etc. all contribute significantly to parasitic drag. You need to visualize a projectile shaft that has passed through rifling when estimating the drag penalty. At best, only smooth-surface drag will be present.
Mechanically, the bearing surface needs to be >1 1/2 calibers in length. Artillery shells typically have an ~2 caliber-long bearing surface. The practical requirements of mass on copper solids used in small arms is >2 calibers. The tail is between 1 caliber, and 1 1/2 calibers in length... as dictated by a boat-tail angle range between 7, and 9 degrees. The balance is left for nose length.
It is a balancing act.
