Triple tround


I’ve got it from Fred, I think, and I don’t remember anything he’s said besides it is used in well drilling when hard rock has to be broken (i.e. non-military cartridge). May anyone add any info about it?


Vlad–It has 3 ceramic bullets and is used, as you were told, in oil wells. It is fired from a special fixture placed on the well head. The rotary bit on the bottom of the drill stem has 3 “Mud” holes. These ceramic bullets fire though the “Mud” holes to break up especially hard rock. This round dates from the Mid-1980’s.


I have a few in my collection (sorry for messy drawer phot) and I believe they are .30 cal ceramic bullets.(not home to meausre them)

I have heard Ron’s aspect and also something about being used in test holes for some type of seismic reading/feedback




Those show up often on the auction sites. A couple of different varieties. They usually sell for about $25 +/-.



Pepper–I don’t think they would be used for seismic sounding. It would not require any bullets for that purpose. Also, note that the bullets are angled which matches the angle of the holes in the drill bit.


I have worked in the Alberta oil field on drilling rigs.
It would be very interesting to see the setup used to fire these trounds .
What was the company name that sold these?

I find it difficult to to believe that this tround “is used in well drilling when hard rock has to be broken .”

Especially considering that the drill string can weigh 200,000 pounds on deeper holes i.e. a 10,000 foot well.
I have a few ideas but nothing to back them up.

There is more to this story…



Glenn–They are also used, I am told, to clear the 3 mud holes in the drill bit when they get clogged with debris, such as stone chips. A lot cheaper to use one of these than to pull the drill string from the hole to clear the drill bit.


I made this pict at the St-Louis show

the box


I also made this pict at SLICS 2008 from a display


Harry, would you happen to have photos of the gun itself?


more trounds :

A producer of trounds.



dardick terra drill


I spent my 36 year career as a drilling contractor and this is the first I have ever heard of this. My specialty was water wells which is the same basic procedures as oil wells. This is very interesting. The Hughes type tri-cone bit that is the standard in both type of drilling does have three hole to let drilling mud flow, however these are at angles. Also as stated many wells are over 10,000’ deep and the pipe these are fired down (supposedly) is filled with a heavy clay and water mixture known as drilling mud. How is a cartridge supposed to travel though thousands of feet of heavy mud, then each turn at just the right time and exit through the three holes? Add to this that the inside of the drill pipe this is shot down is @4" inside diameter. What is going to keep these on a straight course in such a large oversize “gunbarrel”. All this being said, the drill bit shown above is one I have no experence with. If these cartridges are indeed for this type of bit, there is still the problem of shooting it off at the surface and having it travel thousands of feet of heavy mud inside a much larger pipe and have it hit the smaller holes. I am NOT saying it cant be done, but am curious about how it is accomplished. The only way I can imagine it workingis, having the “gun” loaded with these cartridges, lowered down the inside of the drill pipe, to the bottom of the hole and set it on top of the plugged bit. Then triggering the gun to clear the jet holes. Plugged drill bits are big problems in our buisness. It stops the drilling process and results in removal of all the pipe from the hole, and every one of these will be filled with this heavy mud (known as a wet trip). Please more input from people who have used these.


Thank you Aaron322

See:Tround terra-drill processes and apparatus

Processes and apparatus in the field of Terradynamics, e. g. projectile penetration into soils and rocks, employing “open chamber” firing systems using “Trounds” (triangular rounds of ammunition). Included are salvo firings of small calibre projectiles for “shock wave” interaction drilling…

Inventor: David Dardick

Baker Hughes Tricone Bit
This is the standard bit design used on oil drilling rigs (upside down ofcourse).



Gyrojet’s above photo of a SLICS 2008 display was of mine, & in the book which accompanied it I had this to say about #'s 180-183:

David Dardick, Tround International Inc. has developed, along with the help of Dresser Industries, a drill bit that fires ceramic bullets so as to pre-fracture, hard rock
formations at the drill face, still allowing a somewhat conventional drill to work at the same time. Initial testing found this method to be from 200 to 400 percent faster through hard rock formations, and in side-by-side testing the Tround bit showed little wear when compared to the conventional bit. An added benefit is that seismic signal measurement is easily accomplished.
The prototype drill bit was loaded with 500 salvos, with the commercial bid holding 5000 salvos. Working on the open chamber principle, a sensor fires the gun when hard formations are encountered.
These are .25 Cal. Dardick Triplex Tround Rock drilling variations, and a 47.2 grain ceramic projectile. All show a 2-piece case, a copper primer in a copper washed steel battery cup, and three ceramic bullets. We assume the case color variations may pertain to a certain load strength, but are not sure.


TROUND 50 Machine Gun How It Works :