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Molon
18 December 2015, 14:56
A Few Data Points on Hornady Factory Loaded 6.8mm SPC Ammunition

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The test vehicle for this evaluation was a custom upper built around a 16” Noveske Recon barrel chambered for the 6.8mm SPC cartridge. The barrel is stainless steel and has polygonal rifling with a 1:10” twist.




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This comparison is between Hornady’s 110 grain TAP load and the 110 grain V-MAX load. Upon visual inspection, the two loads appear to be identical. Both loads use the 0.277” 110 grain V-MAX bullet with a cannelure. Both loads have a crimp at the case neck (no case mouth sealant.) Both loads have a similar charge of a charcoal colored, short-cut extruded powder. The head-stamp of both loads reads, “Hornady 6.8mm REM SPC”. Both loads have a crimped primer (no primer sealant.) If you were to place a few rounds of each load on a table in front of me, I wouldn’t be able to tell the two loads apart. The 110 grain V-MAX bullet is pictured below along with other bullets of the same caliber produced by Hornady.




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The evaluation began with chronograph testing. Since I already had the chronograph set-up, I also chronographed two other 6.8mm SPC loads from Hornady; their 110 grain BTHP TAP load and the “Custom” 110 grain BTHP/WC load. (Other than the different box that they came in, these two loads also appeared identical to each other.)

An Oehler 35-P chronograph with “proof screen” technology was used in testing. All strings of fire consisted of 10 shots each. All velocities listed are muzzle velocities, as calculated from instrumental velocities using Oehler’s Ballistic Explorer software.





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Accuracy testing was performed from a bench-rest at 100 yards using a Leupold Vari-X III set at 25 power for sighting. Wind conditions were monitored using a Wind Probe. All groups consisted of 10-shots each.

Prior to testing the Hornady ammunition, I fired three 10-shot groups in a row using a control load that utilized hand-loaded 115 Sierra MatchKings. The extreme spreads for those groups measured:

0.99”
1.00”
1.12”

for a 10-shot group grand average of 1.04”. Following my usual procedure for evaluating the accuracy of ammunition, I overlayed these three 10-shot groups on each other using the RSI Shooting Lab software program to form a 30-shot composite group. The mean radius for this 30-shot composite group was 0.37”.


The best 10-shot group of control load . . .

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In order to to give the Hornady ammunition every opportunity to prove itself, I fired five 10-shot groups of the Hornady ammunition from 100 yards and used the best three groups for evaluation. Starting with the Hornady 110 grain TAP load, the three 10-shot groups used for evaluation had extreme spreads of:

1.73”
2.08”
2.14”

for a 10-shot group grand average of 1.98”. As above, these three groups were overlayed on each other to form a 30-shot composite group with a mean radius of 0.69”.



The smallest 10-shot group of 110 TAP

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The three 10-shot groups of the Hornady 110 grain V-MAX load obtained for evaluation had extreme spreads of:

2.43”
2.59”
2.74”

for a 10-shot group grand average of 2.57”. The mean radius for the 30-shot composite group was 0.75” The composite groups are shown below side-by-side for comparison.



The smallest 10-shot group of 110 V-MAX . . .

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30-shot composite groups . . .

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