Fastidious handloaders sim­ply know their reloads will provide the most uniform velocities and the best accuracy when they use the same brand of cases. Cases of different makes can vary in internal volume up to several grains of powder, which can lead to swings in velocity. But by using all one brand of cases, and even cases from the same lot, velocity will be more constant and accuracy the best possible.

After running an experiment with two common cartridges shoot­ing the same make of cases from the same lot and a mix of case brands with a couple of different powders, I can definitely answer seeking perfec­tion via using the same cases may or may not be worth the bother.

The first rifle I tested was a Sav­age Predator Hunter .223 Reming­ton. Barnes 40-grain Varminator bullets were used with H-4198 and W-748 powders in the same lot of Winchester cases and a mix of com­mercial and military cases. Each charge of powder was weighed on a scale, cases trimmed to the same length, the same primers used and all bullets seated to the same depth.

Military cases usually have thicker walls than commercial cases, which can reduce powder capacity somewhat and produce higher pres­sures. So when using military cases, it’s a good idea to back off maxi­mum powder charges a grain or two. The two powders used in the .223 loads were about one grain below maximum and in the military cases showed no signs of excessive pres­sure. The military cases used were Lake City ’83, ’85, ’94 and ’97 for some of the .223 Remington loads listed in the table. Those cases pro­duced most of the faster velocities, showing they had somewhat smaller internal capacities than commercial cases.

The second rifle was a Ruger MKII .30-06. The Ruger is a basic hunting rifle that on an average day groups five shots in about 1.5 inches and on a good day three shots in maybe an inch. For its loads, Berger 168-grain Match bullets were used with W-760 and IMR-4350. The Berger bullets and each powder were loaded in Hornady cases from the same box and Federal, Remington, Hornady, RWS and Winchester cases. Everything else was kept the same.

Follow along with the shooting results listed in the table.

Velocity

With the Ruger .30-06 shooting Berger 168-grain bullets over 52.0 grains of W-760, there was a slightly less extreme spread of velocity with Hornady cases compared to the mixed brands of cases. The relatively high extreme spread of velocity with the Hornady and mixed cases was probably because the 52.0 grains of W-760 did not quite fill any of the cases with the bullets seated. That allowed the powder to settle any which way in the cases and on firing produce a relatively wide extreme spread of velocities.

Extreme spread of velocity is reduced substantially, though, when cases are filled with enough powder that

seating bullets slightly com­presses the powder charge. That is if all the cases are the same make. Seat­ing Berger bullets in Hornady cases slightly compressed 58.0 grains of IMR-4350. With the powder charge locked in one position in cases with the same capacity, extreme spread over five shots dropped down to a decent 19 fps. The same amount of IMR-4350 seemed to be compressed when bullets were seated in the five different brands of .30-06 cases. But the varying case capacities of the five brands still produced three times the velocity spread as cases of all the same brand and capacity.

That extreme spread of veloc­ity was much less evident in the smaller .223 Remington cases. The Barnes 40-grain Varminator bullet seated in various .223 cases slightly compressed 28.0 grains of W-748. With this load fired in Winchester cases the extreme spread was 55 fps. In the five different .223 cases, the spread was 53 fps. Not much differ­ence there.

With 22.0 grains of H-4198 there was a sizable empty space left in all the cases with the Barnes 40-grain bullet seated. Still there was only an extreme spread difference of about 6 fps between the mixed cases and the Winchester cases. However, the extreme spread with the H-4198 load was about half again as much as with W-748.

Accuracy

The Savage Predator Hunter rifle shoots very precisely, and that’s why it was used to shoot the .223 loads.

The Barnes 40-grain bullet with W-748 powder in Winchester cases shot very well at 100 yards with four bullets clustered in .29 inch, and one bullet was a bit high for a five-shot group measuring .82 inch. The bullet that landed high was the first bullet fired. The group fired with the mixed cases had a definite verti­cal string and measured .91 inch. Again the first shot fired landed a bit high from the other four bullets.

The all-Winchester case group was also slightly tighter than the mixed case group shooting H-4198. Four of the 40-grain bullets from the Winchester cases grouped in .44 inch, and alas, the first bullet again hit a smidgen to the left for an overall group size of .71 inch. The mixed case group had a nice, round shape and measured .85 inch.

The Ruger .30-06 with W-760 powder in Hornady cases

grouped five Berger Match bullets in 2.37 inches, with four in 1.22 inches. The mixed case group had no fliers, and all five bullets landed in 1.46 inches.

Shooting IMR-4350 in Hornady cases, the first two bullets hit within .5 inch of each other. The next three bullets landed in nearly one hole but sadly a good inch to   the left of the first two bullets for an overall group size of 1.58

inches. The mixed case group shot the first four bullets in 1.64 inches. The fifth bullet hit an inch to the right for a group size of 2.64 inches.

In the end, this experiment shows uniform velocities come from choos­ing the correct powder as much or more than using all one brand of cases. And in an accurate rifle, a load with all the same make of cases is the path that leads to the best accu­racy. But in a garden variety hunt­ing rifle there is not much, if any, difference in accuracy between loads with all the same cases and cases of different brands.