Single Shot Detachable - Interchangeable Barrel Models From The Bullard Arms Company. An advertisement carried in the February 1888 issue of "The Rifle" states that the Bullard Small Frame detachable model rifle is available in .22, .32 and .38 caliber. The model shown in this gallery is in .32 - .40W with a 28 1/4" barrel and weighs 9 lbs. The serial number of this particular rifle is 3694. The method used for holding the barrel in the receiver was simple, solid and strong. The reason for the Bullard being so rare is that the rifles were hand assembled and were in Bullard's own calibers. Thus, you had to purchase the ammo from Bullard. Finally, they realized they had to provide more standard calibers. The information is from Chapter 6, page 87, in the excellent book "Bullard Arms" by G. Scott Jamieson which was published in 1988.