Hello I've been a Hunter & Target shooter most of my life.Started teaching myself AR Basics a while back but I have a question, does the 300 Blackout have it's own BCG or does it share one with other calibers, Thank you for your help.

300 blackout and 5.56/.223 share the same BCG.

I thought so but I wanted to make sure, thank you for your time & help.

No problem.
Feel free to IM me if you have anymore questions.

Will do & Thanks again.

They do this as they both use the same base cartridge case, just that the .300 Blk case has been cut down a bit and opened up for a slightly larger (7.62) projectile.

You can buy a lil mini circular saw from Harbor Freight and a jig online for cutting down your .223/5.56 brass and making .300 Blk brass.

I didn't know that, Thank you I might try that.

Note of caution since you're new to the cartridge: because of the similarities some 300BO rounds will chamber and fire in a 5.56.

A 0.308" diamete bullet goes a little ways down a 0.223" diameter barrel, then everything explodes.

Keep your ammo totally separate - I use tan magazines for 300blk and black mags for 5.56. I typically don't shoot both during the same range trip as well as an added safety measure.

Note that not all cartridges that use the same parent case use the same bolt head - 6.5 Grendel and 762x39 are examples of this, the Grendel spec has the bolt face deeper in the bolt than the x39, even though same rim diameter, etc.



And if you go this route, you should be aware that some brass ends up too thick in the new neck area and will need to be neck turned.  There is a good list of "known OK" and "known too thick" brass on the reloading sub-forums at  https://www.300blktalk.com/forum/

Personally I'd just spend the $ you'll spend on the saw ($50) and jig ($10-30) on 500-1000 once fired cases on the EE (which is what I did after experimenting with the saw, etc.... dunno what your time is worth, but mine is worth spending 20c/ea on a case instead of making my own)

To add to the above,  a lot of guys install labeled 300blk ejection port covers on their rifles.

Thanks for all the advice,I always keep my ammo separate. At the moment I'm switching over from a 16 inch 12.7x42 (Beowulf 50) to the 10.5 inch 300 Blackout so mixing the ammo up definitely won't be a problem.My pistol is a 5.7x28 so we'll be okay, Thanks all for everything.

I use similar bands & I also only use clear Lancers with the 300BLK & only with 300BLK.  I also have 300BLK marked dust cover, CH & mag catch.