So, if you give a mouse some damaged 5.56 brass...

[hdwhit]

...does he have a choice to do anything with it but to make it into 300 Blackout brass?

That's kind of where I am. I bought a bunch of damaged 5.56 brass in the hopes I could resurrect much of it without too much trouble. And so far that is turning out to be true. But some necks and shoulders are too bad, so cutting it down for conversion to 300 Blackout seems an obvious choice.

I can handle the cut down without too much trouble, but would appreciate some instruction on how to go about forming the cut down 5.56 case into a 300 Blackout case.

Also, does the neck need to be turned or reamed like when 30 Carbine is formed into 22 Spitfire?

Any other caveats to be aware of?

 

[greyling22]

Nope, cut it down, run it through the blackout sizer, then trim to length.

If you Google make blackout brass there are YouTube videos.

 

[mstreddy]

If you give the mouse some damaged brass, then he's going to need a 300 Blackout die set.
If you give him a die set, then he will make 300 Blackout brass out of it.
If he makes 300 Blackout brass out of it, then he will need an upper in 300 Blackout in which to shoot them out of.
If he has a 300 Blackout upper, then he will need a 30 Cal suppressor to enjoy it with.
If he has this suppressor, then he will need a 300 Blackout bolt gun.

Oh, my, what have we started.

OP, depending on head stamps, there are some out there that would need to be neck turned after sizing. On one of the 300 Blackout forums, can't remember which at the moment, there is a list of brass that will form just fine, and those that ends up too thick.
I encountered some myself in a batch that I bought as formed 300 brass. IIRC the headstamps in my case were MKE.
From what I remember the usual Lake City, FC, RP, Win and several others were thin enough in the area where the new neck is formed.
One thing I found that helped me determine the problem when I first encountered it was the Sheridan Engineering slotted case gauge.

 

[kcofohio]

Another question I'd like to throw in the mx. If using converted brass for subsonic, is there a need to anneal the shoulder?

 

[Walkalong]

https://www.thehighroad.org/index.php?threads/making-300-blk-brass.710664/

Lots of videos on utube showing how, from simple (Down your ally I think), to involved and more expensive.

Some brass will be a bit too thick in the neck area.

 

[BrianC636]

If you're going to cut it down, you might look into .277 Wolverine too. Depends on what you want to use the round for.

 

[kcofohio]

https://www.thehighroad.org/index.php?threads/making-300-blk-brass.710664/

Lots of videos on utube showing how, from simple (Down your ally I think), to involved and more expensive.

Some brass will be a bit too thick in the neck area.

Thanks for the link. That pretty much answered my question.

 

[Kaldor]

...does he have a choice to do anything with it but to make it into 300 Blackout brass?

That's kind of where I am. I bought a bunch of damaged 5.56 brass in the hopes I could resurrect much of it without too much trouble. And so far that is turning out to be true. But some necks and shoulders are too bad, so cutting it down for conversion to 300 Blackout seems an obvious choice.

I can handle the cut down without too much trouble, but would appreciate some instruction on how to go about forming the cut down 5.56 case into a 300 Blackout case.

Also, does the neck need to be turned or reamed like when 30 Carbine is formed into 22 Spitfire?

Any other caveats to be aware of?

"Also, does the neck need to be turned or reamed like when 30 Carbine is formed into 22 Spitfire?"
Nope. Cut, form, trim, load.

What bullets do you plan on shooting?
Ive shot bullets from 110-168gr. Best accuracy for my 16" barrel is 125 Hornady SSTs. I have not ventured into heavy bullets for subs, because I dont own a suppressor.

Do you plan on using a small cut off saw to cut to length?
I do this, its slow, but it works. Make sure you buy or make a jig for holding the case so your nickname doesnt become "3 fingers"

Do you have a SSTL media tumbler?
Beats the heck out of manually deburring cases post cut off and trim.

What do you plan on trimming to length with?
I use a WTF2, and it works, but its kind of a bear.

Other wise, its a simple process.
Heres my process assuming Im starting with decapped and decrimped brass.
Cut case at shoulder with saw
Run in SSTL media to remove burrs for an hour
Run thru 300 BO sizing die making sure you have good solid cam over (Hornady in my case)
Trim to length with WTF2
Run in SSTL media to remove burrs and do final case cleaning for about 3-4 hours

I do use a Lyman 30 Carbine M-die and a Lee FCD when loading 300 BO. Light flare to make bullet seating easy, light crimp to close the flare.

Overall my process works, but its slow. I only have about a thousand pieces of 300 BO brass made, and it seems to stand up pretty well as its a lower pressured rifle round. All my cases are LC, as I wanted a common case type and brand.

 

[Browning]

If the mouse will pay for shipping Browning has a 5 gallon paint bucket of once fired .223 brass that isn't damaged in his garage that he'll just give him.

 

[someguy2800]

I do blackout different than most. I just run them in the sizer as is, no cutting first, then trim them to length. Two operations and done.

 

[Walkalong]

Best accuracy for my 16" barrel is 125 Hornady SSTs

Those consistently shoot very well for me also.

 

[Hokie_PhD]

And if you give a guy some 223 brass, a cutoff saw, a set of dies, a 300Blackout upper and some bullets....

Seems like you’d have a happy guy.

 

[HankC]

"no cutting first, then trim them to length"
That is a lot of trimming and maybe why folks cut before or after forming. I bought 300BLK fired brass at less than 10c a piece, save a lot of trouble. If I were to do conversion, I would do it for 277 WLV, but wait on it go SAAMI. If you buy converted 300BLK brass, stick with LC brass. As posted above, some head stamps are too thick for 300BLK.
http://www.300blktalk.com/forum/viewtopic.php?t=88599

 

[hdwhit]

Mstreddy asked:
Oh, my, what have we started.

Something similar happened with 9mm. It seems once you get started loading one caliber, others sort of find your bench like so many stray cats.

 

[Demi-human]

If you give a Three Hundred Blackout to a mouse, he will be commisioned by the cat, to eliminate the dog, so he may revolt against the humans unimpeded.

Beware the cat!

 

[hdwhit]

BrianC636 said:
Depends on what you want to use the round for.

Well, basically, I've pretty much given up on the idea of getting another M1 Carbine, so with brass suitable for conversion to 300 Blackout and a bunch of 308 components that I can't use otherwise, it seemed that making the switch to 300 Blackout was the thing to do.

 

[hdwhit]

Demi-human cautioned:
Beware the cat!

The cat revolution succeeded around my house years ago. We're now supervised by three cats who are quite benevolent overlords.

 

[hdwhit]

Kaldor wrote:
What bullets do you plan on shooting?

To start with, 110 grain M1 Carbine style bullets that were left over from the days when I was loading that cartridge. When those run out, I'll first look at the 125 gr Hornady bullets that you and Walkalong mentioned.

Do you plan on using a small cut off saw to cut to length?

I had seen mention of using a small chop saw like the one Harbor Freight sells and I figured that made a lot of sense.

Thanks for the caution about the jig. My father is a master machinist and even though he's 93, he still likes to tinker, so I may ask him to build one for me. Be sure that if he does, it will be finely crafted, vastly overbuilt, a true work of art and take six months to build, but keeping him engaged seems to keep the Alzheimer's from progressing.

Do you have a SSTL media tumbler?

Yes, I have a rotary tumbler.

What do you plan on trimming to length with?

I've used a Forster trimmer since the 1990's.

Heres my process assuming Im starting with decapped and decrimped brass.
Cut case at shoulder with saw
Run in SSTL media to remove burrs for an hour
Run thru 300 BO sizing die making sure you have good solid cam over (Hornady in my case)
Trim to length with WTF2
Run in SSTL media to remove burrs and do final case cleaning for about 3-4 hours

Thank you for that. A roadmap is quite helpful.

I want to say right now that I'm only thinking in terms of a thousand or so rounds since that's what I've got in the way of 308 projectiles. But I said the same thing about 9mm when I got started and I'm now sitting on 4,500 rounds of processed and primed brass.

 

[Demi-human]

A feline miscreant was brought into my home four months ago, against my will.
Undaunted, I have taught Oreo to fetch, heel and sleep at the foot of the bad. Though he blatantly refuses to chase the mail lady.
We have hawks that keep the mercenary mice at bay, however I don't trust the cat. Or the squirrels. Were Rusty still here, he would agree.

The only thing more comforting than a fourty five in my hand, is a Golden at my knee.

 

[Hokie_PhD]

The only thing more comforting than a fourty five in my hand, is a Golden at my knee.

Goldens are beautiful. But given the choice I’d rather have a German Shepherd by my side. It’s funny how many people are afraid of them.

Of course, the Canadian Eskimo dog in my profile pic is the first in our fami,y not to be a German Shepherd.

 

[someguy2800]

"no cutting first, then trim them to length"
That is a lot of trimming and maybe why folks cut before or after forming. I bought 300BLK fired brass at less than 10c a piece, save a lot of trouble. If I were to do conversion, I would do it for 277 WLV, but wait on it go SAAMI. If you buy converted 300BLK brass, stick with LC brass. As posted above, some head stamps are too thick for 300BLK.
http://www.300blktalk.com/forum/viewtopic.php?t=88599

A cordless drill on a forester trimmer makes quick work of it. It's really fast compared to cutting, sizing, final trimming.

 

[hdwhit]

Hokie_PhD wrote:
I’d rather have a German Shepherd by my side.

Every German Shepherd I've ever encountered (including the one that used to throw himself against the window when I delivered the newspaper and one day came through the window, came over to me, stared me straight in the eye and escorted me to the porch and then escorted me back to the property line) has been intimidating, but not one to be afraid of.

I wanted one for retirement (man is not an apex predator without a dog) but the people in north-central Arkansas where I am headed (when my wife retires) told me that Shepherds don't do well there. Heartworms or something get them early. They recommended a Black & Tan hound.

 

[hdwhit]

someguy2800 wrote:
A cordless drill on a forester trimmer makes quick work of it.

Yeah. But I'll be retired in three weeks so turning the crank on the Forster won't be much of a bother.

 

[ms6852]

I bought the 2” saw from Harbor Freight and the jig that fits this saw from squirrel daddy. They work great.

http://www.squirreldaddy.com/Rigid-Brass-300-Blackout-Case-Trimming-Jig-2-0-p/sd24-105.htm

 

[hdwhit]

Demi-human wrote:
I don't trust the cat.

Next time, get a breed known as a Turkish Van. They're named after the region around Lake Van where they originated. They are known as "water cats" because they will not hesitate to go into water chasing their prey. Some have even been known to swim recreationally. They are fiercely loyal and very protective.