Solventless Bore Cleaning Device
M256 Gun Barrel
Removing Propellant Residue
Introduction and Background Studies
The U.S. Army Research Laboratory (ARL) and Aberdeen Test Center (ATC) have designed and conducted bore cleaning studies on a Solventless Barrel Cleaning Device (SBCD).
New Bore Cleaning Approach
Bore cleaning takes place by manually guiding a spinning brush on the end of a flexible drive shaft up and down the bore for 15–20 min. The brush itself is made from ceramic (silicon carbide) impregnated organic resin matrix spheres or strands which abrade away, along with the bore residues, during the course of cleaning. The combined brush and bore residue can be collected using a vacuum attachment at the muzzle.
Note
Mr. Joseph McDeshen, Chief Artillery Supervisor, ATC, APG, MD , was the first to recognize that the silicon brush system might be useful for cleaning the M256 gun barrel.
Brush Bore-Wear Check
To ensure that the silicon brush would not damage an in-service, high-value barrel by removing its chrome or eroding the exposed steel where chrome is missing, the brush was first tested on scrap sections of M256 tube. However, no measurable bore diameter change accumulated in the region brushed in either section after 105 min of total dry brushing.
Having established from the testing trials of table 1 that the silicon brush (dry or wet) will not damage either the chrome or the exposed steel (where chrome is missing).
Post-Cleaned SBCD Surface Finish
Though the surface finish may appear (figure 3) roughened by the SBCD cleaning process, a surface finish measurement (using a Handysurf E-21A surface texture analyzer, manufactured by Sheffield Measurement) indicates (table 1) the smoothness is on par with that of a new barrel.* Hence the SBCD device does not measurably change the barrel’s surface finish.
Cleaning (DU) Barrels
Because of its high mass density, depleted uranium (DU) is often used as a component in tactical long-rod penetrator designs, such as the M829 family of 120-mm kinetic energy (KE) rounds. On rare occasions, it is possible for trace amounts of DU particles to be left behind in the gun.
To shed some light on this issue and determine the level of hazard that may exist, if any, a known-to-be radioactive barrel (serial no. 10799) was cleaned with the SBCD and the dust collected in a High-Efficiency Particulate Air (HEPA) filtered vacuum system.
BCS Can provide a bore vacuuming attachment to protects the operator from contaminated particles that can damage the lungs and kidneys and can cause respiratory illness.
Conclusions
Test results showed the surface finish of an SBCD-cleaned barrel was comparable to a new barrel. In addition, a radiological survey showed the radiation levels of the SBCD components and evacuated cleaning dust were Not Above normal after cleaning a DU-contaminated barrel.
US Army Approved
These types of bore cleaning systems have been tested and approved for use in the Abrams M256 Smooth Bore.
Electrically Powered Bore Cleaning Systems, utilizing silicon carbide brushes 120 Grit or 180 Grit. Driven by a flexible shaft using No Liquids or Chemical Solvents, and in conjunction with a bore vacuuming attachment. Have been tested and passed for use in the following situations:- Recommended Approval for use at Depots, Proving Grounds, Direct Support, Field Use, M256 Smooth Bore Cannons and in association with the M256 Profile verification program.