The free-float handguards of the rifle rested in a Sinclair Windage Benchrest, while the stock of the rifle rested in a Protektor bunny-ear rear bag. Pictures of shot-groups are posted for documentation.Īll shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The barrel used in the evaluation was free-floated. Also, a control group was fired from the test-rifle used in the evaluation using match-grade, hand-loaded ammunition in order to demonstrate the capability of the barrel. As many of the significant variables as was practicable were controlled for. The shooting set-up will be described in detail below. fliers, target movement, Butterfly Shots). There was absolutely no use of any group-reduction techniques (e.g. This accuracy evaluation used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. I conducted an accuracy (technically, precision) evaluation of the Federal 69 grain Gold Medal Match ammunition following my usual protocol. 77 grain loads running around 2,650 fps compared to 55 grain loads running around 3,250 fps.įor comparison, the mil-spec for M193 allows for a coefficient of variation of approximately 1.2%, while one of my best 77 grain OTM hand-loads, with a muzzle velocity of 2639 PFS and a standard deviation of 4 FPS, has a coefficient of variation of 0.15%. It allows for the comparison of the uniformity of velocity between loads in different velocity spectrums e.g. The muzzle velocity for the 10-shot string of the Federal 69 grain Gold Medal Match ammunition fired from the 20” Colt barrel was 2732 FPS with a standard deviation of 16 FPS and a coefficient of variation of 0.59%.įor those of you who might not be familiar with the coefficient of variation (CV), it is the standard deviation, divided by the mean (average) muzzle velocity and then multiplied by 100 and expressed as a percentage.

When you’re working at this level, the traditional five 5-shot group test simply doesn’t give you statistically valid results.”** “The standard test string was three 10-shot groups, with the most attention paid to the 30-shot composite. It’s interesting to note that pertaining to the accuracy/precision development and multifaceted testing of the Federal ammunition that helped the US Olympians win gold and silver medals in Barcelona, Federal’s Director of Product Engineering, Dave Longren, had this to say: In their 1992 catalog, Federal expanded the nomenclature for this load to “Premium Match” (P223M) and in their 1993 catalog it became “Gold Medal Match” (GM223M) as part of a marketing campaign capitalizing on the USA Shooting Team’s success in the Barcelona Olympics using Federal ammunition. In their 1989 ammunition catalog, the Federal Cartridge Company debuted an addition to its “Match” line-up of factory loaded rifle ammunition a 223 Remington load topped with none other than the Sierra 69 grain MatchKing (223M).

Gorilla ammo ballistics test