To wring out the ammunition and weapons, five-hundred rounds of the Hornady 110-grain OTM were put through three 6.8 SPC uppers, most of it rapid-fire.
Hornady then used their expertise in computer modeling to find the best bullet design. The result was a 110-grain OTM bullet with a very sharp ogive; it appears almost as a spire point instead of a rounded curve to the bullet tip. The bullet was designed for improved terminal performance after passing through intermediate barriers, such as interior walls or car doors. This bullet is not designed for pure target-shooting performance; it sacrifices a slight edge in accuracy to designs like the Sierra MatchKing in favor of increased lethality. The BC of the new 110-grain OTM is 0.360.
Moving to the powder mixture, 6.8 SPC presents the challenge of limited case capacity. To achieve maximum velocity in a given pressure envelope, a slower-burning powder must be used, but doing so can run up against the case capacity limit. Furthermore, the powder must present a pressure profile such that enough gas pressure and dwell time are produced to run the various
As a spent case flies from the ejection port, the rifle is still on-target. Shooters found a compensator helpful in retaining a sight picture through recoil.
The end result is a load designed to work in any 6.8 SPC rifle, from 10-inch full-auto entry carbine to a 16-inch semi-auto for home-defense, ranch use, or law-enforcement patrol. To verify function in the wide variety of 6.8 SPC weapons available, Hornady ran their ammunition through samples of every 6.8 SPC AR-15 upper they could get their hands on. These uppers differ primarily in gas port location and diameter, as well as chamber dimensions.
Besides the new 110-grain OTM load, Hornady also offers a load using their 110-grain V-MAX bullet. This bullet is much more frangible than the OTM, and would make a good choice for small to medium game, or for defense use when over-penetration is a concern.