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Coast to Benicia Arsenal and from all other posts to Frankford Arsenal. Thereafter subcaliber practise will be with three zones covering all ranges from 4,142 to 1,992 yards. The fixt ammunition furnished for this practise will have the 18pound cast-iron shell with propelling charges adjusted for muzzle velocities of respectively 700, 625, and 550 feet per second, and will have the numbers 3, 2, or 1, corresponding to the number of the zone, stencilled in white paint on the projectile. The limits of each zone and other necessary firing data will be found in the special range table prepared for this practise. To insure there being on hand at each post sufficient rounds assembled with the desired propelling charges, requisitions will be submitted for the full number of rounds authorized for the practise, divided equally among the three zones, and for 50 per cent additional rounds, the zones for which these additional rounds will be requested to be determined by the local conditions affecting the practise.

VII. Projectiles for Seacoast Practise.-1. For target practise, unless special instructions are given, capped cast-iron shot or shell only will be used. Plugged shell only will be used, hence with projectiles which are separately loaded, if filled and fuzed shell only are on hand, the fuzes must be removed, the bursting charge withdrawn, and the latter replaced with sand to bring the shell up to its proper weight. Sawdust may be mixt with sand to fill the cavity completely, or the sand may be wet to bring up the weight. The fuze hole should be closed with a brass or iron screw plug, or, in its absence, the fuze may be reinserted. In case the work can not be done at the post with the appliances at hand, the fact will be reported to the Chief of Ordnance. Fixt ammunition will be issued upon requisition, properly prepared, for target practise.

2. Piling projectiles.-Projectiles when received at a post will be unboxed and piled with points to the wall, base out, so that they may be easily inspected and fuzed in case of action.

3. Packing boxes for projectiles.-The packing boxes in which projectiles are received will be kept until the projectiles are used.

4. Painting projectiles.—Projectiles will be painted as required by regulations, Office of Chief of Ordnance, dated June 30, 1898, last revised November 7, 1904, and in case the galleries are wet the projectiles after painting will be slushed. In accordance with these regulations the distinctive color to

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indicate the character of bursting charges will not be applied until the projectiles shall have been filled, after which the entire base of each projectile will at once be painted the required color.

VIII. Care of Empty Metallic Cases and Primers.-After the expenditure of ammunition in target practise with guns using metallic cartridge cases, the empty cases will be taken up on the property return of post as "empty metallic cartridge cases," under the heading provided for that purpose. Immediately after firing the cases will be decapped, well cleaned by washing inside and out, and dried.

Upon the accumulation of convenient lots of such cases they will be packed in the boxes in which received and shipped by posts in the Atlantic, Northern, and Southwestern Divisions to Frankford Arsenal; in the Pacific Division to Benicia Arsenal, and in the Philippines Division to Manila Ordnance Depot.

All obturating electric and friction primer cases will be cleaned immediately after firing and turned in to the post ordnance officer for shipment to Frankford Arsenal, as provided for .30-caliber shell.

IX. Drill Primers.-Drill primers will be used for drill purposes, subcaliber practise, and saluting. They are issued with the "drill-primer outfit," two of the outfits being supplied to each post ordnance officer, who will be charged with the duty of resizing and reloading these primers for use as required. The supply of drill-primer bodies is 100 for each post garrisoned by two companies and 200 for each post garrisoned by three or more companies.

X. Cartridge Storage Cases.-Cartridge storage cases will be carefully handled and when emptied will be promptly returned to the depot or arsenal from which shipped. The crates in which storage cases are received will be carefully preserved for use in return shipment.

XI. Protector Caps.-The protector caps found on the sections of the cartridge in each storage case will be left in the storage case for return shipment.

Weight of projectile (lbs). 1.06

Weight of charge (lbs.):

Brown prismatict.

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XIII. Powder.-1. The weights of the charges, the expected velocities, with other information relative to lots of powder are given in the table following (par. XIV).

2. The charges on hand to be used in target practise, when greater than those here given, will be reduced;* when less, they will be used without change, the corresponding velocity being computed from the formula:

The average value of y is: For nitrocellulose powder, y=1.2; for nitroglycerin powder, y=0.8.

3. For a given weight of charge the velocity increases slightly with the temperature of the powder at the instant of firing, and for a given increase of temperature this increase in velocity varies with the initial velocity.

For all lots of powder tested recently the charges have been adjusted to give the prescribed velocities when fired at the standard temperature of 70°. In the earlier tests only the temperature of the air was recorded, and for these lots but slight error will result from taking this as the temperature of the powder.

According to the data available at present, the following table gives the corrections for temperature:

Normal initial velocities.

833 917 980 1056 1148 1220,2000 2100 2150 2200 2250 2400 2600

26 29 31

30 32 34 38 40

14 15 16 18 19

65.67

25 29

20

21 24 25 41

8 8 9 10 10 17

21

9 10
22 21 26 28
35 37 41 44 47

11 12 13

43 | 44

69

66 67 69

59

53

71 72

66 67

61

54 55 59

46 46 49

33 34 34 36

18 18 19 19

0 0

23 24 26

50 50 52

81 82 84 87

20

01

56 60

92 100

33 37 39 63

35 37 60 62 64

32

To be deducted from normal initial velocity.

28 To be added to normal initial velocity.

This table applies to lots tested at a temperature of 70°. *See Instructions for the preparation and care of powder charges," Form No. 1872, issued by the Ordnance Department, which will be followed in making reductions. Charges for a given zone, weight of projectile, or model of rifle will not be reduced for use with any other zone, weight of projectile, or model of rifle.

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For those lots not tested at 70 information can be obtained from this table for making the desired correction in velocity due to difference in temperature of powder when tested and when fired.

For example, if powder was tested at 60° and the charge fixt for 2,250 f. s. and was fired at 80', from the table the increase in velocity to be expected would be 24+ 1943 feet. The above table applies more particularly to nitrocellulose powders, but may be applied to nitroglycerin powders also with but slight error.

4. The powder charge should not be left in the gun for any considerable time before firing. If a number of rounds have just been fired in the gun, the temperature of the charge might thereby be increased several degrees.

5. The conditions for each shot should be as uniform as practicable. To secure this for the first shot, the bore, including the powder chamber, should be thoroly cleaned before firing. The presence of the lubricant used for protection in the bore of the gun results in a material reduction in the velocity.

6. The percentage of moisture and solvent in powder has a marked effect upon the velocity, and any exposure which would tend to change the percentage present should be avoided.

Smokeless powder should not be exposed to the direct rays of the sun.

7. The changes directed herein should be made in those charges only that are to be used in firing and only immediately before the firing takes place, and unless changes are to be made in the weights of powder charges the bags in which they are put up will not be opened or otherwise disturbed.

8. The weight marked on a charge or a section of a charge of smokeless powder as issued is the weight of the smokeless powder only. It does not include the weight of the igniting powder or of the bag.

9. Any loose powder resulting from reductions directed herein will be disposed of as directed in Circular, No. 12, dated War Department, Washington, September 28, 1903.