Hunter's Supply Cast Slugs 49gr .25cal

Today I did some target testing of the Hunter's Supply Cast Slug Flat Nose 49gr. Test groups were fired from my stock .25 Marauder. I adjusted my rifle for two different velocities. The first set of shots I fired at my usual moderate settings, then turned the Hammer and Spring up to maximum settings for the second set. I used Benjamin Domed 27.8gr pellets as a control group, shot from my bags on my bench at my 25yard target. The manufacturer of these slugs said they were tested with a Marauder, if so, theirs must perform completely different from mine.
Here is the box I received. 100 slugs rolling around in a box. They cost $9.99 from MidwayUSA
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A shot of the slugs.

In the magazine.

They were a bit harder to push into the breach than standard pellets.

First set: Benjamin Domed 27.8gr 763.6FPS 36.0FPE
Hunter's Supply Cast Slug 49gr 594.2FPS 38.43FPE
Second set: Benjamin Domed 27.8gr 884.8FPS 48.34FPE
Hunter's Supply Cast Slug 49gr 688.4FPS 51.57FPE
I didn't bother to measure the groups as the slugs were all over the place.
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Spiraling was very visible. These were a bust in my stock rifle. They may perform in a rifle modified for high power.
 
I have tried the same bullets in my .25 Condor with extreme valve from RL. Same thing! As a matter of fact, I have tried many bullets from Hunter Supply. I hoped for good results because they are economical but not found any I liked for any caliber I have.(.25 Marauder & Condor/.358 Tuned Recluse/ .457 Texan) too bad can't find something good for the price but you're better off just paying more and getting results. Hunting or target shooting...accuracy is first