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Ammunition by Bill Roberts |
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Bullets |
Bullets Bullets used are either groove-lubricated or paper patched lead or lead alloy projectiles. They may be cast and directly used, or if paper patched, may be cast as slugs and then put into a hammer or press swage for final shaping. If the bore is cleaned after each shot, bullets of .001 inch (diameter) oversize may be loaded. The most suitable size, however, is a bullet that is bore diameter or .001 inch undersize. When fired, obturation of the base prevents gas blow-by and consequent inaccuracy. Bullet shape varies widely, and the best shape for each rifle must be determined by experimental shooting. Flat-nose bullets may shoot as well as round-nose ones. Some have experienced difficulty in getting the sharp-or pointed-nose bullets to perform satisfactorily, especially in barrels with a rifling pitch slower than one turn in twenty inches. Grooved bullets are best made from a mould that produces bullets that do not require sizing to bring them to proper diameter. The custom moulds produced by Paul Jones and other makers produce good bullets. Standard moulds from Lyman, NEI, and Dixie Gun Works (Pedersoli made) are good if the correct size is available from their product line. Sizing down .458 inch diameter bullets to .450 inches may distort the bullet enough to ruin its accuracy potential. Weight for .45 caliber bullets may range from 480 grains to 570 grains. Obturation or bump-up of the bullet is very dependent on the bullet's weight and the hardness of the lead or lead-alloy used. The bullet must upset a sufficient amount from the impulse of the burning powder to seal the gas pressure and ride the bore interior to provide accuracy. Match-grade bullets should not vary more than one grain in weight. Bullet base shape also varies greatly. Some of the most common shapes (in longitudinal cross-section) are shown below:
Bullet Base Shape Varieties There seems to be no end to the number of formulas for grooved bullet lubricants. The lubricant must keep the bullet from leading up the bore, and must stay in place in the bullet grooves during hot weather. Lubricants made from animal fat seem to help emulsify the residue when cleaning between shots. The lubricant must be soft enough to help keep powder residue softened. SPG™ bullet lubricant works well, as does Wonder Lube in some rifles. Try mixing your own from anhydrous lanolin using beeswax or Tamarack High Temperature bullet lube from Tamarack Products, Inc. (Box 625, Wauconda, IL, 60064) to harden the lanolin. Paper-patched bullets present unique loading problems. The paper MUST stay in place on the bullet during loading; thus a clean bore is essential. Paper thickness may be varied to provide different tightness of fit of the bullet to the bore. Use of light, thin air-mail paper (.0015 inch thick) has worked well in several rifles. A thin coat of grease, sperm oil, light-weight petroleum oil, or a synthetic lubricant should be applied to the paper immediately prior to loading. |
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© 2004 WA Roberts |
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