coloradokevin
Member
- Joined
- Mar 22, 2008
- Messages
- 3,285
Well, I have to say that I'm thus far fairly impressed by German engineering. On a whim today I decided to drive up to the mountains to do some load testing with my M48 8mm Mauser (a Yugoslavian Mauser).
I've had this rifle for about 5 years now, and originally bought the thing still packed in cosmoline for $90. The guy who sold it to me owned a gun store and was going out of business, so he also threw in a few hundred rounds of old surplus ammo that was dated around 1935 or 1939. Not bad for $90, at least in my estimation!
M48 Mauser:
Anyway, until now I've just been using suprlus ammo in my value-priced rifle, but I recently decided to load some hunting ammo in hopes of someday fielding this rifle as an elk gun.
I loaded 175 grain Sierra Spitzer (soft point) bullets on primed and prepped Remington cases, and then charged these cases with H380 powder in groups of three, ranging from 48 grains of powder to 53.2 grains of powder (for a total of 7 three shot strings). Because this was to be my initial load testing on this rifle/bullet, and due to the fact that I only had 21 pieces of brass available, I started at a charge that was about 10% off of the published maximum charge, and then increased my charge weight by 0.9 grains per string.
The rifle was shot prone, just shy of 100 yards (because I couldn't find 100 yards to use on short notice), using the original sights, and under fairly poor lighting conditions.
My results were a bit variable, which I've come to expect when developing loads. However, when I averaged the 7 strings I came out with an average group size of 1.73". This included two groups with called "flingers"; one of the groups with a flinger had the other two shots sharing a single ragged hole. I also recorded my best 3-shot group at 0.77 inches, and the second best group at 1.02 inches.
BEST GROUP:
Because these groups were shot at a distance of approximately 220-250ft, I'd estimate that this would extrapolate out to an overall average group size of around 2.36 inches, with the best two groups being at 1.05" and 1.40", respectively. Still, given that I was shooting an old Mauser without the benefit of modern sights or a legitimate bench rest, I can't complain with these results in the least! I certainly expect that I'll see improvements in accuracy as I refine my loads for this rifle, and I'm happy to report that my best group was produced using 52.3 grains of powder (which is in a range I'd be comfortable to use for elk loads).
Through this load testing I learned that the windage on my sights needs some serious adjustment, with all groups sitting about 3 inches to the right of my intended target. Unfortunately the old Mauser doesn't come with a "click adjustable" sight system, and I'll have to drift the front sight to correct this problem (I've never found a precise way to accomplish such a task, other than to guess and test... which is tedious).
I also noticed something strange with the extracted spent cartridges from this test. Each cartridge appears to have a black film around the case mouth, and it appears to be something other than burned powder residue. I'm guessing that this could be some leftover packing grease in the chamber? Anyway, I'm open to all suggestions on this one!
Unfired cartridge next to a cartridge that exhibits these strange black marks:
Anyway, I just thought I'd share my Mauser experience for the day! I know these groups aren't at all impressive by varminter standards, but they'll do for me given the platform they were fired from, and the manner in which this testing took place (at dusk from the cold ground, using original sights).
I've had this rifle for about 5 years now, and originally bought the thing still packed in cosmoline for $90. The guy who sold it to me owned a gun store and was going out of business, so he also threw in a few hundred rounds of old surplus ammo that was dated around 1935 or 1939. Not bad for $90, at least in my estimation!
M48 Mauser:
Anyway, until now I've just been using suprlus ammo in my value-priced rifle, but I recently decided to load some hunting ammo in hopes of someday fielding this rifle as an elk gun.
I loaded 175 grain Sierra Spitzer (soft point) bullets on primed and prepped Remington cases, and then charged these cases with H380 powder in groups of three, ranging from 48 grains of powder to 53.2 grains of powder (for a total of 7 three shot strings). Because this was to be my initial load testing on this rifle/bullet, and due to the fact that I only had 21 pieces of brass available, I started at a charge that was about 10% off of the published maximum charge, and then increased my charge weight by 0.9 grains per string.
The rifle was shot prone, just shy of 100 yards (because I couldn't find 100 yards to use on short notice), using the original sights, and under fairly poor lighting conditions.
My results were a bit variable, which I've come to expect when developing loads. However, when I averaged the 7 strings I came out with an average group size of 1.73". This included two groups with called "flingers"; one of the groups with a flinger had the other two shots sharing a single ragged hole. I also recorded my best 3-shot group at 0.77 inches, and the second best group at 1.02 inches.
BEST GROUP:
Because these groups were shot at a distance of approximately 220-250ft, I'd estimate that this would extrapolate out to an overall average group size of around 2.36 inches, with the best two groups being at 1.05" and 1.40", respectively. Still, given that I was shooting an old Mauser without the benefit of modern sights or a legitimate bench rest, I can't complain with these results in the least! I certainly expect that I'll see improvements in accuracy as I refine my loads for this rifle, and I'm happy to report that my best group was produced using 52.3 grains of powder (which is in a range I'd be comfortable to use for elk loads).
Through this load testing I learned that the windage on my sights needs some serious adjustment, with all groups sitting about 3 inches to the right of my intended target. Unfortunately the old Mauser doesn't come with a "click adjustable" sight system, and I'll have to drift the front sight to correct this problem (I've never found a precise way to accomplish such a task, other than to guess and test... which is tedious).
I also noticed something strange with the extracted spent cartridges from this test. Each cartridge appears to have a black film around the case mouth, and it appears to be something other than burned powder residue. I'm guessing that this could be some leftover packing grease in the chamber? Anyway, I'm open to all suggestions on this one!
Unfired cartridge next to a cartridge that exhibits these strange black marks:
Anyway, I just thought I'd share my Mauser experience for the day! I know these groups aren't at all impressive by varminter standards, but they'll do for me given the platform they were fired from, and the manner in which this testing took place (at dusk from the cold ground, using original sights).
