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| $ 3.50 per Cartridge |
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| 300 Whisper |
| ("Parent Cartridge") |
| The 300 Whisper was developed by
J.D. Jones of SSK Industries for the Thompson/Center Contender Single Shot Pistol or Rifle. It was a Proprietary Cartridge as Cor-Bon use to make it, but due to brass problems it is no longer produced by any manufacturer at this time. It is made by necking out the .221 Remington Fireball from .22 caliber to .300 caliber, which also reduces the case neck angle from 29 degrees to 23 degrees. These specimens have a Lake City Head Stamp. |
| Wildcat |
| 300 Whisper |
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| $ 6.00 Cartridge in Labeled Sleeve |
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| Cartridge |
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| .221 Remington Fireball |
| ,, |
| ,, |
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| .221 Fireball |
| .221 Fireball |
| .221 Fireball |
| .300 Whisper |
| .300 Whisper |
| .300 Whisper |