MVT Methyl Violet Test Apparatus

MVT Methyl Violet Test Apparatus

The MVT™ (Methyl Violet Test) apparatus is used for the traditional determination of the chemical stability of firearm propellants or other energetic materials by the measurement of the time interval needed to evolve nitrogen oxide gases from the heated sample. Methyl Violet Indicator Papers are used for the detection of the presence of decomposition gases. The test temperature is typically set at 120°C or 134.5°C. The nitrate esters decompose evolving nitrogen oxide gases which are detected by means of a standardized  color change of the Methyl Violet Indicator Paper- OZM Research® supplies the highest quality of indicator paper--guaranteed to meet US Navy specifications and is currently being utilized and accredited by the USA Military.

The testing period is extremely brief. Simply insert the test tubes with the sample into heating block and the moment the color change occurs on the indicator paper the test is complete.


The MVT™ apparatus is designed especially for quality control of single-base and double-base firearm and rocket propellants. It can also be used for testing other materials and mixtures containing nitrocellulose, nitroglycerine, or other organic nitrates if desired.

The MVT™ belongs to a group of methods based on the change of color of indicator papers in addition to the Abel test (ABT™), Heat test (CH100™)  or the Vieille test. These tests differ from each other in terms of the measurement of temperature, weight of the sample, size and shape of the heating tubes or the kind of indicator paper used. They are well suited for comparing various batches of propellants-but less useful for comparing different types of compounds.The typical sample mass is 2,5g and the measured temperature ranges between 120 or 134°C with a testing period from several minutes to 5hours.

The MVT™ is simple and reliable-enough so to be an fine independent complementary method to the vacuum stability test (STABIL VI®) or  the high performance liquid chromatography apparatus (HPLC-OZM1220™).


The MVT™apparatus consists of one heavy, aluminum heating block with 26 test tube holder holes (also model with 10 holes is available as a standard).  Each tube is covered with an individual lid equipped with a small hook. The indicator paper is then conveniently hung on the hook which is placed inside the tube when the lid is secured. OZM Research™ supplies the highest quality of indicator paper--guaranteed to meet US Navy specifications and is currently being utilized and accredited by the USA Military.

The glass test tubes (with the tested samples and indicator paper) are inserted into their holders in the heating block. The temperature of the block is administered by a control unit which is comprised of an operational controller and a limit controller. The limit controller operates an independent alarm circuit which halts the heating process if temperatures were to accidentally increase above specified safety limits. Calibrated digital thermometers may be used to correct and control the temperature of the heating block.

The MVT´s™ standard heavy, aluminum heating block can hold and measure up to 26 samples (with individual time exposures for each one).  Heating blocks with a different desired number of holes are available on request.


  • Safer operation--the aluminum heating block is much safer compared to a traditional reflux heating bath
  • Customized heating blocks available upon request
  • High precision and accuracy of the heating block temperature
  • Fast operation time and proven testing procedures
  • Independent alarm circuit led by the limit controller eliminates prolonged accidental overheating



  • MIL-STD-286C

order of the questions about MVT Methyl Violet Test Apparatus

OZM Explosives testing instruments Stability tests MVT Methyl Violet Test Apparatus
OZM Research s.r.o.