Avoid
Like many of us, I buy ammo in bulk when I run across a good sale. I purchased a 300 Grizzly Cartridge Ammo box in 300 Blackout from Sportsman Warehouse here in Columbia, SC. I use ammo on the first in, first out principle with ammo and finally opened this box 18 months after purchase.
I have a Wilson Combat SBR with Suppressor and wanted to see how the ammo performed. I fired several rounds and was alerted when the breach did not seat. The round had jammed in the chamber to the point I could not pull the slide back. I took the rifle to my gunsmith, who removed the jammed round. He told me most of the ammo in the clip was out of spec. I reload ammo, so I went home and put his ammo through a Blackout 300 Case Gauge and checked for OCL (Overall CartridgeLength). For those unfamiliar with case gauges, you drop the round in the gauge, and the base of the round should be flush with the top. Eighty percent of the ammo did not pass the case gauge test; only a few rounds exceeded the OCL.
I called Sportsman Warehouse, and they told me to contact the manufacturer as it had been too long to return the ammo. I called Grizzly multiple times and sent several emails. There was no response to my email, even though the woman I spoke to acknowledged she had passed them on to the owner. I felt sorry for her as she was the one who had to take my calls; her responses, the owner had just stepped out, the owner was in a meeting, the owner is aware of your calls, I have told the owner, the owner will be back in 2 hours, etc.
All I ever asked was for him to stand behind his ammo. I have posted photos of the Box Label and a Case Gauge showing the round is out of spec.
If you buy ammo from this guy, check it closely. I consider this ammo dangerous to shoot and have since disassembled it.
Check these guys out before you buy. They have a history of making bad ammo and not refunding your money.