I haven't seen the slugs, but I've shot a few of the mini shells with # 8 shot. From what I can tell, the shells are made for reduced noise and reduced recoil. They work well in my 12 ga SXS coach gun, but don't feed in the 870 ( too short). I fired one by manually loading it. The recoil was about 1/2 that of 00 Buck, but the noise was considerably less. I believe they are mad in Mexico and distributed by Aguila. Velocity is right up there with standard loads since the shot charge is reduced in proportion with the powder. A box of 20 ran me around $8.00, which is pretty steep. I kept 4 of them for use in the SXS as a house backup.( mainly for critters, if it need shooting and is bigger than a bunny or a grondhog, I have the 870)
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