making 300 BO brass question

[Scooby]

I have read tons and tons of threads on making 300 BO brass from 223, however I still have a question or two. I have 2000 LC 78 brass, I have de-primed, swaged primer pockets, and cut them all down with an ebay jig on the 6" harbor freight chop saw. Now for my questions If I wet tumble with stainless steel pins will it remove the cut off remnants from the chop saw? Also will the brass harden from wet tumbling in pins, do I need to anneal before forming to 300BO? Am I better off just using the inside and outside rcbs tool instead of wet tumbling to get the brass remnants off? I just don't want to make brass that isn't going to have a long service life.

Thank You

[Omega]

Short answer, is yes. Here are my steps when I convert these cases, this was after I got my Lyman prep station, so I can chamfer and deburr more often.

I deprime with a Lee universal depriming die
Remove the primer crimp and (optional)uniform the primer hole.
Cut the cases, then chamfer and debur the cut.
Lube and size the cases.
Trim, chamfer and debur.
Tumble.

This keeps my cases free of any lube until I load them, and since I add a bit of car wax to the wet tumbler, they stay relatively shiny until then. I haven't, yet, annealed any, but I ordered an annealer so this may change. I haven't lost any to cracked necks yet though, so I don't think the conversion or wet tumbling hardens them much, if any, I think it gets work hardened when resized.

[Omega]

Oh, BTW, here is what gets left after tumbling my 300Blk and 277 WLV cases after this process.

279002

[Jsm180]

I decap, cut to rough length on the bandsaw, anneal, size, trim to 1.365 and then wet tumble for 3-4 hours. For me, the wet tumble removes most of the trim bur and any remaining bur can be removed when I cut the primer crimp if needed. I tried some without annealing and it took a lot more pressure to form.

[JimB..]

Brass will not harden from wet tumbling with pins.

Wet tumbling with pins will not eliminate, replace or replicate the advantages of chamfering the case mouth.

[Conditor22]

Good and bad brass inconverting 223/556 to 300BO


Good
ADI PERFECTA
Aguila PMC
A USA PS
FC PSD
GFL RA
HB RP
Hornady SSA
Hornady (nickel TAA
IK03 Tula
IMI TW
IVI TZZ
LC WCC
M193 Winchester
Norinco WIN NT
NOSLER WMA 15



Thick neck wall, bad without neck turning:

AB 556 L2A2
ATI MKE13
CBC MPA
CJ6 Norma
CJ 8 NPA
DNL PMC
FNM PMP
FRONTIER PPU
GECO RAM
Hot Shot RORG
HRTRS RWS
ICC S&B
IK03 SADU
IMI TAA
IVI SADU
KFA Wolf Brass

First I swage all the primer pockets on my Dillon 600, (I have a spring on the swage rod and 223 brass is more manageable than 300 BO brass coming off the rod)
I used a trim jig and an HF chop saw. Cut close to length, deburred the outside full length sized, trimmed, wet tumbled, chamfered, deburred.


Now for my questions:
If I wet tumble with stainless steel pins will it remove the cut off remnants from the chop saw? ---Not all
Also, will the brass harden from wet tumbling in pins, -- I haven't found wet tumbling to work harden brass
do I need to anneal before forming to 300BO? --- I didn't have to anneal before full-length sizing
Am I better off just using the inside and outside rcbs tool instead of wet tumbling to get the brass remnants off? ---debur the outside before FL sizing then chamfer and deburr (inside and outside) after trimming to the final length. Brass will stretch a little when you FL size
I just don't want to make brass that isn't going to have a long service life. --- You could anneal before FL sizing if you want.

Thank You

[Ford SD]

I do it different

I pick a lot of 223/556 brass with a neck thickness 10-11

aneal
remove the decaping assembly ..lube and size in the 300 bo die
using a jig in a band saw cut to length plus .010 or so
trim to length
water wash/ tumble clean/dry only needs 15 min
final size/ deprime

its ready to load

more steps than most but i like to be able to discard rejects at the sizing step, if the shoulder or neck has any flaws

[Faret]

I do it different

I pick a lot of 223/556 brass with a neck thickness 10-11

aneal
remove the decaping assembly ..lube and size in the 300 bo die
using a jig in a band saw cut to length plus .010 or so
trim to length
water wash/ tumble clean/dry only needs 15 min
final size/ deprime

its ready to load

more steps than most but i like to be able to discard rejects at the sizing step, if the shoulder or neck has any flaws

So how does the neck get expanded?

[popper]

So how does the neck get expanded? Uh, sizing die.
Rough cut is not accurate enough, still need trimming and chamfur.
Annealing helps as you made the neck out of the body which was never annealed from the factory.
Omega's process is correct, I would anneal after the chopping. You also may need to outside turn as the LC brass body is thicker than normal neck thickness. Depends on the gun.

[Faret]

Not if the expanding button is removed with the decapping assembly. I just did not see a expanding step in the list?

[rboeser]

You should confirm the outside diameter with a GOOD caliper or I prefer to use a micrometer after loading as was said thick wall brass can force you to neck turn if the round will not fit the chamber of your rifle or rifles. Always good to know your ammo will work when you need it.

[Brassmonkey]

anyone here ever use fired blanks? to form into .300 bo

[rboeser]

Not that I know of. If the crimp from the blank is short enough, it should work. You need to remove most of the original neck anyway.

On second thought, you better dissect several cases and measure wall thickness. You never know, they may be thinner walled brass and not made to handle the pressure.

[Cosmic_Charlie]

I recently started loading .223 again after many years. A buddy gave me a coffee can of LC brass and he has primers too. I ordered a Little Crow .223 case trimmer and it works great. Fast too. If you are converting a pile to 300 BO you might check them out. I'm sure they make them for the BO and it would save a bunch of time and improve the process.

[jonp]

Short answer, is yes. Here are my steps when I convert these cases, this was after I got my Lyman prep station, so I can chamfer and deburr more often.

I deprime with a Lee universal depriming die
Remove the primer crimp and (optional)uniform the primer hole.
Cut the cases, then chamfer and debur the cut.
Lube and size the cases.
Trim, chamfer and debur.
Tumble.

This keeps my cases free of any lube until I load them, and since I add a bit of car wax to the wet tumbler, they stay relatively shiny until then. I haven't, yet, annealed any, but I ordered an annealer so this may change. I haven't lost any to cracked necks yet though, so I don't think the conversion or wet tumbling hardens them much, if any, I think it gets work hardened when resized.

This is the method I've used and have had good success. I also have not annealed any and do not use a wet tumbler. If you have an annealer then it probably wouldn't be a bad idea but I haven't seen as to how it's necessary.

[Ed_Shot]

anyone here ever use fired blanks? to form into .300 bo

Fired 5.56 blanks work perfectly for forming 300 BO brass. Got mine while the getting was good from Everglades Ammo.

BTW: Lake City uses the same brass for military ball or blank ammo.

[gunfan2]

Thanks for a very informative reading regarding forming 300 blackout. I was having a little problem with making mine from 221 Fireball brass, used it because it didn't have to be trimmed so much, but had problems with a split in the area where the shoulder meets the neck.

[JohnFreeman]

Fired blanks work fine for 300 BO Brass. Have done many.

[Whole Bunches]

anyone here ever use fired blanks? to form into .300 bo

Have shot Blackout formed from blanks thousands of rounds. No problems.

[gundoctor]

anyone here ever use fired blanks? to form into .300 bo

Here is my method of forming blanks into 300BO

1st: Tumble until clean,
2nd: Form case in Redding file trim die & cut of excess length with saws-all
3rd: Resize & deprime
4th: Final trim with LEE case trimer
5th: Swage primer pocket with RCBS primer pocket swage.
6th: Champer neck
Final steps: Prime case, add powder, seat bullet & crimp.

The saws-all makes trimming faster than any other method I've tried. The LEE case trimmer cleans up any jigged edges the Saws-all leaves.

I do the final trim in a drill press. Something that helps with that is a tool I made from a pair of needle nose plyers.
I ground a 3/8" radius in the wire cutter section of each jaw, then glued in a thin strip of leather in each jaw to protect the case from scratches & keep it from turning.

[Rapier]

I use split necks to make my whisper brass, just do the major cut at the bottom of the shoulder and run the brass, one pass through a RCBS, FLSD, then in a 3 way cutter on a RCBS Pro Trimmer. My brass is already swaged. No annealing is ever needed. I shoot mostly 230g cast, PC with a can.

I have a steady supply of trimable brass, with the cats I shoot.

[Cgaengineer]

I use split necks to make my whisper brass, just do the major cut at the bottom of the shoulder and run the brass, one pass through a RCBS, FLSD, then in a 3 way cutter on a RCBS Pro Trimmer. My brass is already swaged. No annealing is ever needed. I shoot mostly 230g cast, PC with a can.

I have a steady supply of trimable brass, with the cats I shoot.

You notice and deposits in your can shooting PC bullets? I’m casting the Lee 220’s and am powder coating them to shoot through my Sandman L.

[Tradbowhunter]

I cut down brass to length with harbor freight saw and squirrel daddy jig. After that I chamfer mouth so not to have jagged edge going into die. I lube cases well and run them through the 300 blackout die this also deprimes them. Then trim the newly formed brass to length. I have messed with different headstamps known to have issues with this conversion and never had a problem with any of them I dont really look at head stamps anymore. My die set is Hornady. The only reason I bring this up is because a buddy of mine has a set of LEE dies and does sort through his head stamps as he has issues with some brass not chambering in his gun.

[CWME]

I run the cases through my dillion 650 with the RT1500 trimmer installed. I have a FL size die after the trimmer to pop the primer and make sure the cases are uniform. Wet tumble, dry, load on the Dillion 1050. First die in the 1050 is a Lyman M die to flair the necks a touch. Irons out any bur and helps when seating a bullet. I can crank out a couple thousand in short order between both presses.