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PostPosted: Wed Feb 27, 2019 8:29 pm 
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Joined: Sat Nov 03, 2007 4:19 pm
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Location: Coalmont BC
I did a soap penetration test today, comparing the 26.7 gr. NOE Hunter pellet to a 25.4 gr. JSB King, both fired from my regulated 2560 which shoots at 52 FPE.... Here are the recovered pellets, side and front view....

Image

Image

The head of the NOE pellet after impact was a few thou larger than the head of the JSB.... The JSB shortened a few thou more than the NOE, probably because I used 40:1 alloy (2.5% tin) to cast the NOE instead of pure lead.... The Meplat of the NOE pellet increased in diameter from 0.160" to 0.210", and showed a noticeable cupping as it expanded.... Even though the NOE pellet had a slightly greater SD because it is 1.3 gr. heavier, the penetration was a bit less, 120 mm instead of 130 mm.... showing that it is dumping energy faster during penetration as the flat nose of the pellet expands....

While this is not a perfect comparison with how the NOE Hunter pellet will perform on game, it is certainly an indication that is is doing what it was designed to do.... 8)

Bob

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Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
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PostPosted: Wed Feb 27, 2019 9:02 pm 
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Joined: Fri Jan 22, 2010 1:17 pm
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Location: Kingston, ON
Nice rifling marks on both of them.
Did you measure fpe during the test, are they both roughly 52 fpe?
Just curious. Good stuff as always!

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PostPosted: Wed Feb 27, 2019 10:03 pm 
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I did not check the velocity during the tests, but I did about a week ago when I tested the NOE pellet and it was virtually the same FPE as the JSBs.... The gun is regulated and I fired 2 shots to settle it before doing the penetration tests....

Bob

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Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!


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PostPosted: Thu Feb 28, 2019 10:47 pm 
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Location: P.G. B.C.
I would expect the flat point to pen. less, of course, due to the cupping and cavitation that would be caused.

Have you tried the 51gr. NOE's for penetration in soap, Bob?

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Daryl


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PostPosted: Thu Feb 28, 2019 11:34 pm 
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Location: Coalmont BC
I tried one at 100 FPE, and the nose expanded to just over bore size, about 7 mm, then the bullet tumbled.... It only penetrated 155 mm, while the predicted value was 219 mm.... I also tried the 48 gr. HP version at the same 100 FPE and the base portion penetrated 85 mm.... The nose of the bullet came apart into many fragments, the base mushroomed....

I may have a photo somewhere, I'll see if I can find it.... Better yet, I found a link.... topic72908.html

Bob

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Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!


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PostPosted: Fri Mar 01, 2019 4:55 am 
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Joined: Mon Aug 24, 2015 4:56 pm
Posts: 489
Location: SW Ontario
All your pellet/slug designs built by NOE have a flat or hollow point which are fine for hunting. I am wondering how accurate they are at 100 yards with their lower BC?


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PostPosted: Fri Mar 01, 2019 11:41 am 
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Location: Coalmont BC
Accuracy has nothing to do with the BC.... and my BBTs have a better BC than flat based bullets of the same SD because of the boattail.... There are a few BCs at the link in the last post.... In addition, Meplats do not increase the drag in the Subsonic region, in fact they often have less drag than a round nosed bullet of the same weight.... Read up on Elmer Keith's work, and Robert McCoy's "McDrag" program, developed at the Aberdeen Proving Grounds.... which is used in the Kolbe Drag Calculator.... http://www.geoffrey-kolbe.com/drag.htm

The pellets I have designed for NOE are so new that there are no BC's available yet, but I expect them to be similar to Exacts or Baracudas, and better than pointed pellets or hollowpoints…. That is based on an analysis of the nose using the Kolbe calculator and some CFD work, but measurements are the only way to know for sure.... There are several people using the Hunter and Hunter Magnum pellets that are reporting accuracy to be on a par with JSBs, but that has been within 50 yards, nobody has shot them at 100 yet, to my knowledge....

Bob

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Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!


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PostPosted: Fri Mar 01, 2019 5:08 pm 
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Joined: Wed Jan 05, 2011 12:35 pm
Posts: 11301
Location: P.G. B.C.
I sold my NOE .25 cal. DC mould with one cavity a HP to a local friend, and have been casting with a 4cavity FN BT and
moly coating them.
When the warmer weather arrives, I will be doing some longer range shooting with the Condor & will publish the results
here.
I thought I read somewhere, the expected BC would be about .100 for the FNBT, which is considerably higher than
the Diabolo shapes, as it should be. The bullet, as well, should be much more stable in the transonic speed zones.

Sub-sonic speeds raises the bar, in much reduced velocity loss.

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Daryl


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