royinidaho
Well-Known Member
With your media testing device. I can see from the photo that the media is not under pressure buy the way that the lid opened up and the media spilt out the top. The quantity and quality of material is variable depending on conditions.
Good point. The amount of media exiting the device was less than a few onces (very little). There is about an inch of space above the media and the bottom of the lid.
Pressure from the bullet seemed to direct media flow more in the direction of the bullet but the lid did have to raise considerably for media to exit the rear.
I think it would be better if the media was under some pressure. Makes sense. Currently the media is water soaked and is hand compressed to about the consistency of a good meat loaf. How can one describe a feel.
Maybe a better device would be more square in shape with an open top. My first attempt was a rectangular box 24" long and about 10" wide. Every thing was screwed together including the top cover. The first shot from the 338 RUM with SMKs immediately reduced it to its component pieces which were quite wide spread.
The next attempt was to rig the device inside of a 25 gallon heavy plastic barrel. A shelf was made within the barrel then the device components held in place with pressure from the barrel. The top cover was allowed to set unfastened on top. A cover closed over the device. The media was contained in a large plastic garbage bag.
The sides were displaced with each shot from any large rifle cartridge but were more easily contained and repositioned.
The device pictured is made of main line irrigation plastic pipe with a 200 PSI pressure rating. The only place for media to flow is out the top.
Fill the box with media and place a neat fitting wooden plate on top of the media.
Then place 25kg to 100kg or so on top of the wooden plate depending on the size of the plate. The plate would press down on top of the media and supply a level of internal pressure. This could then be calculated in in/lb3, kg.m3 or whatever.
You could adjust the weight on top of the box until the desired internal pressure was obtained.
As the internal pressure can now be controlled, a more consistent comparison can be made between bullets. A problem is, that since the media (specially treated and conditioned peat moss) is mixed with water the density of the media increases with depth.
As I ponder your suggestion it would seem to me that not only would what you suggest provide increased consistency between comparisons, consistency throughout the medial would be increased. Thus shots anywhere in the media would produce more consistent results.
Simply remove the weight and top wooden plate to access the material and retrieve the spent bullets. When you replace the lid and weight, conditions should be back to original and ready for the next test shot.
Just a thought.
Good thoughts!
Thank you.
I'll get on it in the morning.
Sorry for rambling but it helps me to think out loud, so to speak.
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