I use the Lee Factory Crimp as extra insurance in case a 300BLK round finds its way into a 223 magazine/rifle. Additionally the crimp is supposed to increase accuracy by delivering a more consistent pressure curve as the bullet enters the rifling, whether the bullet has a cannelure or not.
I recently picked up some 300BLK range brass and there happened to be a loaded round with them. I'm guessing they weren't reloads, or they would have picked up that tidy shiny pile. The loaded bullet pulled VERY EASILY out of the brass with a hammer style puller. I have to really smack my reloads to get them to move out of the brass. That round would have been a definite KaBoom in a 223/5.56.
I finally got around to removing the firing pin and trying to chamber 300BLK rounds into a 223 chamber.
It pushed the round into the cartridge 0.02"-0.0037", but they wouldn't chamber.
Before attempt:
Bolt didn't seat:
After attempt:
I wasn't able to locate the info/articles I started with ~8+ years ago. Here's a few things I dug up.
From the article link below, "The only problem I ran into while handloading the .300 Blackout was with bullet set-out when the cartridge was chambered. With some loads—particularly those using the 125-grain Nosler AccuBond and 150-grain Nosler Ballistic Tip—the bullet would migrate forward in the case when the cartridge entered the chamber. This had a horrible effect on accuracy."
https://www.shootingillustrated.com/articles/2014/6/17/handloading-the-300-aac-blackout/
*edit* My 300BLK are ARs, not bolt Guns.
I recently picked up some 300BLK range brass and there happened to be a loaded round with them. I'm guessing they weren't reloads, or they would have picked up that tidy shiny pile. The loaded bullet pulled VERY EASILY out of the brass with a hammer style puller. I have to really smack my reloads to get them to move out of the brass. That round would have been a definite KaBoom in a 223/5.56.
I finally got around to removing the firing pin and trying to chamber 300BLK rounds into a 223 chamber.
It pushed the round into the cartridge 0.02"-0.0037", but they wouldn't chamber.
Before attempt:
Bolt didn't seat:
After attempt:
I wasn't able to locate the info/articles I started with ~8+ years ago. Here's a few things I dug up.
From the article link below, "The only problem I ran into while handloading the .300 Blackout was with bullet set-out when the cartridge was chambered. With some loads—particularly those using the 125-grain Nosler AccuBond and 150-grain Nosler Ballistic Tip—the bullet would migrate forward in the case when the cartridge entered the chamber. This had a horrible effect on accuracy."
https://www.shootingillustrated.com/articles/2014/6/17/handloading-the-300-aac-blackout/
*edit* My 300BLK are ARs, not bolt Guns.
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