(g) If the swabbing solution or the standard metal-fouling solution is not available, the barrel should be scrubbed, as already described, with the soda solution, dried, and oiled with a light oil.  At the end of 24 hours it should again be cleaned, when it will usually be found to have “sweated”; that is, rust having formed under the smear of metal fouling where powder fouling was present, the surface is puffed up.  Usually a second cleaning is sufficient, but to insure safety it should be again examined at the end of a few days, before final oiling.  The swabbing solution should always be used, if available, for it must be remembered that each puff when the bore “sweats” is an incipient rust pit.

(h) A clean dry surface having been obtained, to prevent rust it is necessary to coat every portion of this surface with a film of neutral oil.  If the protection required is but temporary and the arm is to be cleaned or fired in a few days, sperm oil may be used.  This is easily applied and easily removed, but has not sufficient body to hold its surface for more than a few days.  If rifles are to be prepared for storage or shipment, a heavier oil, such as cosmic, must be used.

(i) In preparing arms for storage or shipment they should be cleaned with particular care, using the metal-fouling solution as described above.  Care should be taken, insured by careful inspection on succeeding day or days, that the cleaning is properly done and all traces of ammonia solution removed.  The bore is then ready to be coated with cosmic.  At ordinary temperatures cosmic is not fluid.  In order, therefore, to insure that every part of the surface is coated with a film of oil the cosmic should be warmed.  Apply the cosmic first with a brush; then, with the breech plugged, fill the barrel to the muzzle, pour out the surplus, remove the breechblock, and allow to drain.  It is believed that more rifles are ruined by improper preparation for storage than from any other cause.  If the bore is not clean when oiled—­that is, if powder fouling is present or rust has started—­a half inch of cosmic on the outside will not stop its action, and the barrel will be ruined.  Remember that the surface must be perfectly cleaned before the heavy oil is applied.  If the instructions as given above are carefully followed, arms may be stored for years without harm.

(j) Preparation of solutions: 

Sodasolution_—­This should be a saturated solution or sal soda (bicarbonate of soda).  A strength of at least 20 per cent is necessary.  The spoon referred to in the following directions is the model 1910 spoon issued in the mess outfit.

Sal soda, one-fourth pound, or four (4) heaping spoonfuls.

Water, 1 pint or cup, model of 1910, to upper rivets.

The sal soda will dissolve more readily in hot water.

Swabbingsolution_.—­Ammonium persulphate, 60 grains, one-half spoonful smoothed off.