I spent most of the last two days working on my .25 FX King, setting it up and testing 10 different slugs across two velocity platforms. Some will be critical because this initial testing was only completed on my 18 yard indoor range, but my experience over the last couple of decades is that if I can't get the combination to shoot sub MOA at 18 yards (.18"), it certainly won't shoot sub MOA at 100 yards. By eliminating wind, lighting, temperature, and other variables, I have never failed to come really close to the ideal regulator, velocity, and ammo combination using the indoor close range set-up, and then fine tuning once I get outside and apply to longer yardages.
The .25 King came in from Utah Airguns with the reg pressure not even up to 130. It was shooting the 33.95 gr pellet at about 920. As referenced below, I boosted the initial slug test reg pressure to about 139, setting the macro setting at 23, and the micro setting at just over 3. The test results can be seen below, with the H&N Heavy Slugs in .249 shooting the tightest 10 shot group averages.
I then boosted the Reg pressure to 150, and set the micro setting up to just under 3 1/2 and shot the 33/34 grain slugs, boosting the micro setting to about 3 3/4 for the slugs >34.5 grains.
All of the results can be seen below. It is really interesting to see which slugs had the groups open up, and which ones the groups tightened up with the velocity increase.
My plan is to leave the rifle set-up as is, and as the next step, test the four slugs shooting the tightest two 10 shot group averages at the longest distance available to me, which is just over 84 yards. Once I determine which one performs the best (shoots the tightest 10 shot groups) at the longer distance, I will set-up my dope chart and lock in my scope adjustments for that particular slug combination, after I play with the velocities for that combination a little more, to be certain I have it optimized.
For those interested, the last test I did today was to see how many shots I could get before it fell off the regulator, starting with a 250 BAR fill. It dropped off the reg on shot #30. I can live with that given the power output I am getting.
Also, I was really impressed with the appearance and packaging of the Alteros slugs. Not being a hollow point, I don't what the terminal effect difference will be on game, but they are certainly pleasing to the eye to look at and extremely consistent in appearance and performance.
I will report back with the 84 yard test results once time and weather permit. Given winter is starting to make its presence known, it may be a while before conditions are right.
The .25 King came in from Utah Airguns with the reg pressure not even up to 130. It was shooting the 33.95 gr pellet at about 920. As referenced below, I boosted the initial slug test reg pressure to about 139, setting the macro setting at 23, and the micro setting at just over 3. The test results can be seen below, with the H&N Heavy Slugs in .249 shooting the tightest 10 shot group averages.
I then boosted the Reg pressure to 150, and set the micro setting up to just under 3 1/2 and shot the 33/34 grain slugs, boosting the micro setting to about 3 3/4 for the slugs >34.5 grains.
All of the results can be seen below. It is really interesting to see which slugs had the groups open up, and which ones the groups tightened up with the velocity increase.
My plan is to leave the rifle set-up as is, and as the next step, test the four slugs shooting the tightest two 10 shot group averages at the longest distance available to me, which is just over 84 yards. Once I determine which one performs the best (shoots the tightest 10 shot groups) at the longer distance, I will set-up my dope chart and lock in my scope adjustments for that particular slug combination, after I play with the velocities for that combination a little more, to be certain I have it optimized.
For those interested, the last test I did today was to see how many shots I could get before it fell off the regulator, starting with a 250 BAR fill. It dropped off the reg on shot #30. I can live with that given the power output I am getting.
Also, I was really impressed with the appearance and packaging of the Alteros slugs. Not being a hollow point, I don't what the terminal effect difference will be on game, but they are certainly pleasing to the eye to look at and extremely consistent in appearance and performance.
I will report back with the 84 yard test results once time and weather permit. Given winter is starting to make its presence known, it may be a while before conditions are right.
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