Let's talk about 300 Blackout..

[civilian75]

My process...
1. Chop saw .223 to 1.380 give or take
2. Resize/deprime
3. Anneal
4. Trim to 1.368 with RCBS 3-way trimmer
5. Load normal operation in Dillon

I would trim to something like 1.355" to 1.358". You should consider 1.368" as the case maximum length. The 300 AAC Blackout site, hand loading section ( <broken link removed> ) indicates a case length of 1.368 +0.000 / -0.020.

I am not annealing my plinking loads brass. But I read here "I haven't seen any case life benefits by annealing, but ES and SD are lower when using annealed brass."

 

[FORKLIFT252]

Out of a 9" barrel
125 gr herters hollow point
18 gr lil gun
Winchester WSR primer
2025 fps.

 

[FORKLIFT252]

Would WC872 and WC867 work for power?
I know it's meant for 50 cal... but how about a
168 gr. or 220 gr (super/ sub)
One could get 8lb. for 35.00 sure would bring down cost.

 

[arakboss]

For making the brass, if you want to be cheap. Just use a pipe cutter and cut the .223 case off at the base of the throat. Size it with a 300 BO die (or 221 fireball die). Trim, chamf and debur. I've found that the S&B cases are a bit thick and the rounds wont chamber unless you ream the neck first. A case gauge is great way to go to ensure that your rounds will chamber. LC brass is great, never had an issue with it and it's usually plentiful at the range.

As for Powders H110 works pretty well for SuperSonic. AA1680 is good for subsonic heavy pills.

If you start with once fired 223 brass do you have to anneal it first before running through the 300BO die?

 

[edzz]

If you start with once fired 223 brass do you have to anneal it first before running through the 300BO die?

No.

 

[MobileTaylor]

Wow, this is an old thread that was revived. Starline has 300BO brass for around .27 cents each. In stock. I purchased some and like it. Just an FYI.

 

[arakboss]

Wow, this is an old thread that was revived. Starline has 300BO brass for around .27 cents each. In stock. I purchased some and like it. Just an FYI.

That is a good deal. I just spent $13 on a pipe cutter so I am going to try processing a few of my own. How many loads can you get out of Starline brass without annealing?

 

[MobileTaylor]

That is a good deal. I just spent $13 on a pipe cutter so I am going to try processing a few of my own. How many loads can you get out of Starline brass without annealing?

Not sure yet. I haven't made it through the new 500 pieces of brass yet.