New to 300 Blackout ( used 223/556 Questions)

St Pauli

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Durham region
I understand you can trim 223/556 to 300 BO

What tool do I use? I've seen some youtube on the subject but they are all homemade rigs.
Is there a commercially available product that does this? I'm pretty new to reloading but some experience in 30-30 and 6.5 x55 and
8mm next to learn along with 300 BO.

Should I favour 223 brass over 556 ?
Anything else you can add will help.

Cheers
 
I use a small chopsaw (from harbor freight in the US) to cut the cases
223 brass is thinner than 5.56 and as such it is preferred
mind you, 223 brass is sometimes too thick like PMC so you'll need to add an extra step to ream the brass
I personally form 300blk from Federal, Remington, Winchester and Norinco to 300 blk
 
Let me know how it goes for ya. After doing 400pcs over a several weekends, I think I'm just gonna buy ready-made brass. That's a whole lot of sore fingers and elbow grease.
 
I bought a 6 inch chop saw from Princess Auto and use it to cut the brass off at the shoulder, then it gets deburred before FL sizing, then trimmed to length and inside/outside chamferred.
I use Remington 223 brass exclusively as I had lots of it and I find that it is nice brass to work with and converts easily without neck turning or any other special treatment.
I've purchased other items to help speed things up like the RCBS case prep center which recently got replaced with the Frankford Arsenal case trim and prep center.

300BLK is a great round, you'll have a lot of fun loading for it. Just remember that it's not a shrunk down 308, you will not get the velocities of a 308 and therefore it's ability to be used as a hunting cartridge is limited to shorter ranges.

Are you loading for a bolt action or a semi? Loading for a bolt action opens up a lot of options. For a semi auto you also need to buy the right powders to load for it if you want it to cycle. I use H110 for 110gr-150gr projectiles (supersonic), Lil'Gun for 150gr-170gr projectiles (supersonic), and A1680 for the 150-208gr projectiles. A1680 and a 208gr Hornady are what I use for subsonics.
In a bolt action powder choice is less important and I've got some loads using Trailboss and 150gr FMJ's for some fun subsonic plinkers.

There are other powders that will work well with the 300BLK and I'm looking forward to trying some of the CFE300 when I can find some, I've simply listed what I've had the best luck with over the last few years.
 
I will be bringing large quantities of .300 Blackout to market here shortly. It will be converted from commercial .223 brass or 5.56 NATO, depending on what my supplies look like. I have all the tooling in place, I am just working on getting my optical headstamp sorter performing at a level that is acceptable.

Pricing will be more reasonable then what is currently available in Canada. I am hoping inside a couple of weeks it will be ready.
 
Are you loading for a bolt action or a semi?


A pump rifle , I bought Win 296 powder . It will be my 100 yard deer rifle .

Ive got some 300 brass but I see tons of 223/556 at the range I don't want to let goto waste.
 
Let me know how it goes for ya. After doing 400pcs over a several weekends, I think I'm just gonna buy ready-made brass. That's a whole lot of sore fingers and elbow grease.

I've already "converted" about 1000 cases which should last me a while
The 300blk I've seen for sale is incredibly expensive.
 
Have converted a couple thousand Norinco cases. Its not a super quick process no. Started to build a press mounted 1/4hp router setup that I can incorporate into my empty station on progressive but haven't completed it just yet.


I've done everything thus far using a small harbour freight type saw with a homemade aluminum jig in it to cut to rough length. Then a lee quick trim and a cordless drill in single stage press after forming with FL die.

To me its worth it as I've got very consistent brass for peanuts in dollars, just a few weeknights of my time.
 
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I prefer to use the Norinco cases (a close match to Winchester) as they are not headstamped with the Caliber (usually C J 95).

I use a "Harbor Freight" type saw paired with an aluminum cutting jig that I picked up off eBay.

1) cut the deprimed 223/5.56 cases to 1.365" with trim saw & jig
2) de-burr cut end
3) spray with liquid lanolin & alcohol lube
4) full-length resize, rotate half-turn and resize again (.300 BLK die)
5) trim to 1.368" with LEE QuickTrim or Case Length Gauge
6) de-burr case mouth
7) dry tumble for an hour to remove lube
8) anneal (as necessary)
 
first thing I do is run the 223 brass through my sizing die with the recapping pin remove, cut, trim and size with pin back in. I found this order of operations reduces the amount of trimming as they be cut to almost perfect length.
 
I think I've put together the best setup you can have for converting brass without using a Dillon powder trimmer....

I start out with Remington 223 brass
Cut it with the Harbour Freight mini chop saw with the aluminum jig that you can buy online
De-burr on my Lyman Case Prep Express
Re-size and deprime with RCBS SB dies
Trim with the Little Crow Gun Works Worlds Finest Trimmer
Chamfer and de-burr again on the Lyman
Load with 15.0gr of Lil Gun and 150gr FMJBT's
 
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