Case vibration

Velvet

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Joined
Nov 5, 2017
Messages
209
Wouldn't you be forced into increasing your COAL? And how well would a powder burn if you eliminate/minimize flame channels between the kernels?
In my case, the bullet is jamming. Have a short troat, and I'm forced to introduce a lot of bullet in the case.
One solution would be to extend the troat so that I only seat the diameter of the bullet or so. This would free up space.
But it involves sending the rifle to a gunsmith
 

jpndave

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Jan 12, 2006
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490
Location
Hyde Park, UT
This case charging technique is described in detail in a loading manual by Mic McPherson. The title is METALLIC CARTRIDGE HANDLOADING - PURSUIT OF THE PERFECT CARTIDGE. The discussion on swirl charging is on page 181, and it's very interesting. He contends that uniformity in the way the kernels are stacked in the cartridge case from load to load is actually more important to consistency than the uniformity of the weight of the powder charge. It seems like a bit of a stretch, but he has tested it thoroughly and says it makes all the difference. He also discusses the matter of dropped charges vs. weighed charges, which is interesting stuff as well. The rest of the manual is also a very good read, as this guy really picks the fly-specks out of the pepper. He covers every topic you might have a question about. I haven't tried his charging method yet, but I certainly intend to do so. I can't think of a reason not to, really. It shouldn't take any longer, or require any extra effort.

Thanks for the feedback on this. I have his book "McPherson on Leverguns". It is a bit discombobulated as it is a compilation of articles but the information is excellent. I have been debating on his other books. I'll get a copy of the reloading book.
 

nicholasjohn

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Feb 12, 2019
Messages
880
Location
Vancouver, WA
Thanks for the feedback on this. I have his book "McPherson on Leverguns". It is a bit discombobulated as it is a compilation of articles but the information is excellent. I have been debating on his other books. I'll get a copy of the reloading book.

I haven't seen that book yet, but I certainly do like his book about handloading. It's a highly-detailed manual, and I couldn't just sit down and read it like a story book. It's one of those that I had to stop and think about at the end of every paragraph, and digest what I had read as I visualize what he was describing. It was very well written, and most of the content seems like it was written from experience. There were some discussions that were somewhat theoretical, about how things work from an engineer's perspective. I don't know what this guy's day job was before he started writing books & manuals, but it was probably something pretty technical. He may even be one of those "rocket surgeons" we hear so much about ………..
 

John Klingenberg

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Nov 13, 2018
Messages
887
Location
Michigan
Hello boys.
I'm looking for a way to compress more the powder in the case.
The cartridge is 243ai.
Using a 25" drop tube, 50.8g of H1000 enters the case, reaching the shoulder and neck junction.
The bullet is the 105gn Hornady Match.
This recipe, together with the CBTO found, allows me to achieve sub .5moa consistently.
When entering the bullet, obviously a resistance is generated, and also the loss of concentricity, which I want to avoid, compressing the powder more so that there is more free space.
Has anyone tried any type of vibrator that makes the powder kernels fit better?
A friend suggested I try the cell phone vibrators, but I wanted to ask if there was an existing method or device.
Thanks in advance
V
Vortex lab shaker, about a hundred bucks on amazon or cheaper used on the ebay
 

Velvet

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Joined
Nov 5, 2017
Messages
209
Hi guys
I performed some tests with satisfactory results.
With the joystick motor of a PS2, placed at one end of a reloading tray, the cases vibrate a lot, and the powder settles quite well.
As you can see, I had to put weight because if not, they vibrate a lot, with the risk that the powder will jump out of the case.
It occurs to me that placing 4 springs in the corners (as in the tumblers), I would avoid putting the weights. Placing the motor with the vertical axis, in the center and on the underside of the tray, would be an improvement as well.
A voltage regulator would be another improvement.
It helps a lot if we place a weight inside the mouth of the case, which compresses the powder as it vibrates. The necks were not rectified, that's why the bullet could go down freely, and there I discovered that it works.
Well, I hope it helped.
V
 

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nicholasjohn

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Joined
Feb 12, 2019
Messages
880
Location
Vancouver, WA
Hi guys
I performed some tests with satisfactory results.
With the joystick motor of a PS2, placed at one end of a reloading tray, the cases vibrate a lot, and the powder settles quite well.
As you can see, I had to put weight because if not, they vibrate a lot, with the risk that the powder will jump out of the case.
It occurs to me that placing 4 springs in the corners (as in the tumblers), I would avoid putting the weights. Placing the motor with the vertical axis, in the center and on the underside of the tray, would be an improvement as well.
A voltage regulator would be another improvement.
It helps a lot if we place a weight inside the mouth of the case, which compresses the powder as it vibrates. The necks were not rectified, that's why the bullet could go down freely, and there I discovered that it works.
Well, I hope it helped.
V

I wonder if you set the loading tray on something soft, like a folded towel ( or maybe a foam mouse-pad ) it would dampen the vibration enough to keep all the powder from coming out of the case necks. The reason I suggest this is because if you do it with a full loading tray, you won't be able to put the lead weights on it. Have you tried anything like this ???
 

Velvet

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Joined
Nov 5, 2017
Messages
209
I wonder if you set the loading tray on something soft, like a folded towel ( or maybe a foam mouse-pad ) it would dampen the vibration enough to keep all the powder from coming out of the case necks. The reason I suggest this is because if you do it with a full loading tray, you won't be able to put the lead weights on it. Have you tried anything like this ???
I did not try it until now. But my idea is to place the rotor in the center and bottom face of the tray. That way, I couldn't support it on anything except the 4 spring-loaded corner screws.
 
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