Good idea, Douglas, and while there are several interesting concepts discussed in this thread’s past postings, only the truly interested will want to read through the four pages as I did last night. To give credit to the clearly descriptive language defining the term most open-to-interpretation, Blast Effect, we must credit Double D. with “sudden, uncontrolled release of high pressure gasses from the opening of the chamber” or words to that effect. Credit must go to Rocklock 1 for creating the best mental image of the concept of Blast Effect, that of “shooting a 100 pound anvil off of another inverted 100 pound anvil with one pound of black powder” or words to that effect.
We follow the basic 5 step Scientific Method out of habit, as it usually yields results that either confirm or deny accuracy of the stated hypothesis. The steps are:
1. Observation
2. Hypothesis
3. Prediction
4. Experimentation
5. Conclusion
In the first step called Observation you should describe a phenomenon which you have personally observed, such as this one: I have observed that very short mortars seem to throw their projectiles approximately three quarters as far as howitzers of the same bore size, projectile weight and powder load.
Our Hypothesis is a simple statement that defines what we think the outcome of our experiments will be. We believe that the phenomenon termed blast effect can provide the lift needed by a short tubed mortar to achieve more than one half the range of similarly loaded howitzers.
The Prediction should narrow your expectation of what the experiments will show. We for instance believe that the addition of a two caliber long tube will increase the range of the standard projectile only by 30% over the Zero Caliber mortar.
In the Experimentation step of the scientific method we will attempt to perform all of the range experiments in sets of 10 shots with each different length of tube, while keeping all other conditions such as projectile size, shape and weight and powder charge and method of ignition the same for each shot in each set. The only variable will be the tube length. We will have five sets of ten shots each for each of the tube lengths which are: zero cal., ½ cal., 1 cal., 1 1/2 cal., and 2 cal. For a total of 50 shots.
A Conclusion supported by your observation of experiments and notation of results can be reached via use of simple math which can determine the percentage of change in the projectiles average range for each length of tube and logical comparisons can be made agreeing with or not agreeing with the stated Hypothesis. You cannot Prove or Disprove the Hypothesis with one set of experiments as errors can be contained in them which can be negated by having larger numbers of experiments or independent verification of the same experiments necessary for proof or disproof.
Before the professional fireworks provided by our tax dollars grace the skies over Broomfield on Independence Day, we should have a “Quick-Look” at the results of the experiments accomplished on that day. We will shoot the shortest, Zero Caliber Mortar and the longest, Two Caliber Mortar five times each which should give all of us a good indication of whether the Hypothesis will be supported or not.
You will all know if the dynamic cannon making duo is rocketing into the stratosphere or muttering the last words of Edward G., the infamous villain in
Little Caesar, “Mother of mercy, is this the end of Rico?”
Tracy and Mike
This is the linstock we will use as it it a French Companie de l'Artillerie one from around 1750. We like it for firing the big ones and very short mortars with lots of muzzle blast!! The shaft is seven feet long and has an eleven inch long spear point, which gives you excellent reach in case some pesky Englishman, armed with one of those Brown Bess muskets, makes it through your artillery barrage.
