O
  O. M. — Heavy, home-made buffalo rifle, oak half stock with sowbelly butt.  Remington Cast Steel barrel. Initials "O.M.", cut in pewter fore-end  tip, both sides. 
    O. N.— Initials of Noble Orr, U. S. Inspector of Arms, 1799-1801. 
    O. W. A. — Initials of O. W. Ainsworth, U. S. Inspector of Arms  within years 1831-1850.
    OAKE, C. & SON — Jacksonville, Florida. Side-by-side, combination  percussion rifle-and-shotgun equipped with back-action locks. 
    OAKES, Samuel— Philadelphia, Pa., before and after 1800. 
    Oakes,  Samuel—Riflemaker of Philadelphia, about 1800.
    Oberholser,  Christian—-A  Committee of Safety gunsmith of Lancaster, Pa., 1775-76.
    OBERHOLTZER, Christian— Lancaster, Pa., arms maker to Com mittee of Safety,  1775-77. Excused by the Executive Council from military duties on Dec. 5, 1777,  for the making of arms for the Commonwealth of Pennsylvania, in the employ and  under direction of William Henry I of Lancaster. 
    OBERTEUFFER, C. A.— Phila., Pa. Brass barrel flintlock pistol with lock probably by Spang & Wallace. 
    OBLINGER, David and Walter— Piqua, Ohio, 1870-88. 
    Oblinger,  David and Walter—Gunmakers of Piqua, Ohio. Father and son, David  was active 1859 to 1890 when the firm name became Oblinger & Son. Active 1892  or later as repairmen.
    OBLINGER, S.— Troy, Ohio, 1869-78. 
    Oblinger,  Sol—Gunmaker of Troy, Ohio, 1868-77.
    ODELL, S.— Natchez, Miss. Kentucky rifles. 
    ODLIN, John— Boston, Mass. 1671-82. 
    OFFREY, P.— Gunsmith, 173 Chartres, New Orleans, La., 1853. 
    OGDEN, C. — Owego, N. Y. Three-barrel percussion gun. 
    OGDEN, J.— Owego, N. Y. (Related to C. Ogden?) 
    OGDEN, W. & C. — Owego, N. Y. Percussion period. Prolific workmen. 
    OHLENHAUSEN— Wooster, Wayne Co., Ohio. 
    Old,  James—Ironmaster. Supplied Pennsylvania with cannon and shot in 1776. Received  >£1,500 for his services. Location unknown.
    OLDHAM, Thomas— East St. Clair Township, Bedford Co., Pa., 1850.  Maker of Kentucky rifles. 
    OLIVIER, John— 37 George St., Baltimore, Md., 1810. 
    OLMSTEAD, Morgan L.— Auburn, N. Y. 
    O'MARA BROTHERS— Detroit, Mich., 1865-70? A three barrel gun, two  rifles side by side with shotgun barrel underneath. 
    O'NEAL — Unlocated. Rifle maker. 
    O'NEAL, David— Geary near Kearny, San Francisco, Calif., 1858. 
    ONG, E.— Philadelphia, Pa., before and after 1773-77. Had worked at the State Gun  Factory, at Philadelphia, under Peter Dehaven. 
    Ong, E.—G unsmith  of Philadelphia, 1773-77. Employed by Peter Dcllaven at the State Gun Factory,  1776.
    ORAHOOD, J.— Bellefontaine, Ohio, 1858. Percussion  rifles. 
    ORGILL BROS. & CO.— Memphis, Tenn., 1860. 
    ORMSBY, E. S.— Unlocated. Pill-lock revolving rifle. 
    ORR, Hugh — Came to America from Scotland and established at  Bridgewater, Mass., in 1737. Is known to have made 500 stands of muskets for  the Province of Massachusetts Bay in 1748, which arms were subsequently removed  by the British on their evacua tion of Boston in 1776. Orr was active as an  arms maker during the Revolutionary War. Born at Lochinwinioch in January,  1717; died in December, 1798. 
    Orr,  Hugh—Born January 13, 1717, at Lochinwinioch, Scotland. Came to America and  established in Bridgewater, Mass., in 1737. In 1745 he made 500 stand of arms  for the Province of Massachusetts Bay, believed to be the first public firearms  produced in the colonies. Orr also erected a cannon foundry which supplied iron  and brass cannon to the Continentals in sizes from 3-pounders to 42- pounders.  Very active during the Revolution, Orr died in 1798. (Pg. 487, Vol. II,  National Cyclopaedia of American Biography, White, New York, 1929.)
    Orr,  James—Born July 22, 1796, in Westmoreland County, Pa. Established in Belmont  County, Ohio in 1830. Engaged in riflemaking until i860 when he quite in favor  of a more profitable business of wagon making. Died in September, 1887. A fine  workman in metal and wood, his rifles were of high quality.
    ORR, Noble— U. S. Inspector of Arms 1799-1801. His initial  "ON" are found on Whitney contract musket stocks. 
    ORR, Robert — Son of Hugh Orr. Appointed Master Armorer at Springfield  Armory in 1795. 
    Orr,  Robert—Son of Hugh. Worked with his father in Bridgewater during the Revolution  and became Master Armourer of Springfield Arsenal in 1795.
    OSBORN, Lot— Waterbury, Conn., 1776-77. Musket maker to the state.  Arms marked with name or initials and "S. C." for State of  Connecticut. Received payment for thirty-seven guns without bayonets and  thirty-seven with bayonets; Jan. 14, 1779.
    Osborn,  Lot—Gunsmith of Waterbury, Conn. Active 1772-77 he produced muskets for the  state which bore his name or initials and the stamp “S. C.” for the State of  Connecticut.
    OSBORNE, H. — Springfield, Mass., musket maker before and after  1812-21. 
    Osborne,  H.—Riflemaker of Springfield, Mass., about 1820-30.
    OSGOOD GUN WORKS— Norwich, Conn., about 1880. Rim-fire  "Duplex" and "Monarch" revolvers. 
    Osgood  Gun Works—Norwich, Conn. Produced the “Duplex” double barrel, nine shot revolver.  This arm is on the principle of the Le Mat save that the barrels are hinged at  the bottom of the frame to swing up to load.
    OSHKOSH TRAP GUN CO.— Oshkosh, Wis. About 1910. Cheap, single barrel  shotguns. 
    Ostrander  Repeating Gun Co.—San Francisco, Calif. Made repeating shotguns,  1892-93
    Oswan,  Frederick—Riflemaker, Harpers Ferry, Va., 1810-16.
    OVERBAUGH, C. E.— 300 Broadway, New York, N. Y., before and after  1879-87. Top action target rifles. 
    OVERLY, Peter— Kentucky. About 1812. 
    OVERTON, J. — Arkadelphia, Ark., percussion period. 
    Owen  Bros.; Owen, Robert G.—Modern gunmakers at Sanquoit, N. Y., 1921-23.  Robert G. Owen located at Tucson, Arizona for a time and is now with  Winchester.
    OWENS, E. G.— Denver, Col., 1879-80. 
    Owens,  E. G.—Gunmaker of Denver, Colo., 1877-80, before and after.
    OWENS, Lemuel— Zanesville, Muskigum Co., Ohio, 1810-20.