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Beaufort Naval Armorers Signal Cannons

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Bronze Eprouvette Mortar 1 Bronze Eprouvette Mortar 2
Bronze Eprouvette Mortar 3 Bronze Eprouvette Mortar 4

The original Eprouvette Mortar design was used in the 1700’s and 1800’s for testing and grading of black powder. The ‘BNA Eprouvette’ is a custom casting made exclusively for Beaufort Naval Armorers. It is the only BNA cannon type that is manufactured from a casting. It is cast from high strength manganese bronze and the mortar base is part of the casting.

Machine shop labor is used to “Artisan Craft” each rough casting. Each mortar is completely lathe bored to assure structural integrity and a clean smooth bore. The powder chamber and vent are added, and all outer surfaces are machinery cut, polished, and finished.

The bore is golf ball size. These mortars can be blank fired. They are heavy duty small mortars.

Weight is 6.25 Lbs.
Height is 4.5” Length is 5.5” Width is 3.25”

As a note: All other BNA cannon barrels are fully machined and manufactured from rolled shaft stock with no casting involved.

View the eprouvette mortar pricing page for more information.

Getting Loud Blank Reports from BNA Eprouvettes:

BNA Eprouvettes are vented for fuses. They have a powder chamber that is to nominal print-scale size. It is not much of a charge for this strong little mortar. It takes some practice to achieve a really loud blank shot with this mortar. ‘Very fine’ (ffffg) black powder and a liberal amount of not over-tightly packed wadding should be used to help get a loud report. (If the wadding is over-tightly packed, it comes out too easily. The theory is to allow the charge of black powder to do a bit of its own packing when the mortar is discharged.) Looser packing of generous wadding in small mortars helps raise the pressure. Just a note: A more typically shaped longer cannon barrel has the longer bore which is full of air to raise pressure and that makes loud reports easier to achieve.

BNA Replica Eprouvette Mortars are very strong pieces. They are also a very convenient size. This mortar design has been high pressure safety tested by BNA with iron shot that cleared a one third of a mile range. A golf ball fired from an Eprovette will go higher than Tiger Woods can drive it but not much further, maybe 300 yards or so, golf balls can only go so far.

NOTE: The above is not to be confused with or interpreted to be the firing instructions

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