Making 300BO from .223

[orientalexpress]

For you guys that are cutting down .223 brass to make 300 blackout, are you fire forming or not? I've read online that some people are fire forming and some people aren't. I can't seem to find a clear answer to whether it HAD to be done.

[smopoim86]

No. This is what I've done for the 1000 or so pieces I made. If your time is worth much, buy it already prepped.

1. rough cut with mini saw
   
2. deprime
   
3. tumble (stainless media). some of the brass I'm using is pretty rough looking
   
4. size
   
5. trim
   
6. load
   

[Caster]

Nope.

There's a few ways to do it that'll work. There's no ONE right way.

I remove the decapping pin/expander ball from the sizing die and run a 223 case in. That forms the shoulder but the neck is wayyy undersized. Next I chop it off with a cut off wheel. Deburr the inside and then I run it through a Lyman M die. That brings the neck out to where it should be. Last step is to run it through my Little Crow WFT and deburr it.

I do it this way because I use a lot of cast bullets and I would have to use the m die anyway. This way allows me to do the whole conversion with no lube. By not using lube, I can use the primed LC cases David sells. I don't have to worry about my spray lube contaminating a primer.

To date I've had zero issues clambering a round. To date I have made over 3K.

Edited October 1, 2012 by Caster

[Lumber_Jack]

No. This is what I've done for the 1000 or so pieces I made. If your time is worth much, buy it already prepped.

1. rough cut with mini saw
   
2. deprime
   
3. tumble (stainless media). some of the brass I'm using is pretty rough looking
   
4. size
   
5. trim
   
6. load
   

Just jumpin in here, do you have a jig or something to use with the mini saw, to get it close without actually measuring each one.

[Caster]

Just jumpin in here, do you have a jig or something to use with the mini saw, to get it close without actually measuring each one.

That's another benefit to my method. When you run it through the die you have two shoulders. The new blackout shoulder and the old 223 shoulder. It's easy to see where to cut it off at.

[jcoosi]

I just buy already converted

[Caster]

I just buy already converted

By far the easiest method. Price is dropping as popularity increases.

Edited October 1, 2012 by Caster

[orientalexpress]

I know how to cut, size etc. I've loaded about 20 or so purposely unpowered, however I'm just confused as to whether I need to fire form it. If I can avoid the time and effort of fire forming to make a slighlty more accurate round I'd like to however if it's something that needs to be done I will.

[Dolomite_supafly]

Don't worry about fire forming. The process of sizing works great and I can't see a difference between sized and fired brass.

The reason to fireform is to gain extra capacity. No amount of fireforming is going to give you extra case capacity with the 300.

Dolomite

[orientalexpress]

Thanks. I didn't think it would make a huge difference but I wasn't sure. The info that's available is a bit confusing.

[mikegideon]

Just jumpin in here, do you have a jig or something to use with the mini saw, to get it close without actually measuring each one.

I made a jig for mine. Most of the brass I've done was primed Lake city.

1. Cut the case

2. Size without decapping pin

3. Tumble off lube

4. Trim with RCBS power trimmer with 3 way cutting head. I've done 700 or so.

[Jonnin]

plumber's tube cutter does a great job if the 223 will fit, not sure, I was cutting bigger cases than this. Makes a really clean cut very fast.

[mikegideon]

The chop saw takes about a second to load the jig and cut. Besides, you have to cut right below the shoulder. The cut is pretty clean. Certainly much cleaner than an abrasive wheel. No significant burrs. My setup is similar to this. I spent more time on my jig. It has a front guide and a guid for depth. So, I can just slam it into position...

#! Edited October 1, 2012 by mikegideon

[Lumber_Jack]

Describe the jig and what you used, Mike.

[mikegideon]

I'll shoot a pic. Here's a little drawing. 1" x 1/8" aluminum bar and a block of 3/4" Plywood...

[dlm37015]

i talk other people out of what they have

[mikegideon]

i talk other people out of what they have

Yep. I get my brass for Ole' Tender Knuckles

[Caster]

Yep. I get my brass for Ole' Tender Knuckles

Don't blame that one on David. I talked myself into that one.

I'm over at David's house one day, he shows me some piles of primed brass he says he wants to make some 300 brass out of. Never having made any to speak of, maybe a dozen, I speak up like Big Pete and say "You want me to do some of them for ya?" What was he supposed to say, "No I don't want you to save me from hours of finger blistering labor." :rofl:

I'm glad of it though, sore knuckles and a few thousand swear words later I can honestly say, I'm pretty dang good at making BLK brass. :bowrofl:

In typical David fashion, he MORE than made it worth my while. Not that I need to be compensated, I'm more than happy to do it for guy like him.

I might would charge you double Mike, just for the "Ole Tender Knuckles" bit that I just have a feeling, will carry on from you to me for a long time coming.

Edited October 1, 2012 by Caster

[Dolomite_supafly]

Describe the jig and what you used, Mike.

Here is another jig for the chop saw from Harbor Freight.

http://www.300blktalk.com/forum/viewtopic.php?f=179&t=80842

Dolomite

[Clod Stomper]

I bought one of these recently.

http://www.ebay.com/itm/300AAC-Blackout-7-62x40-Wilson-Tac-CTS-Case-Trimmer/271065682501?ssPageName=WDVW&rd=1&ih=017&category=71114&cmd=ViewItem

I haven't used it yet. I don't have my dies. It's set for 7.62x40 right now, but it can be used for the .300 AAC. It indexes off of the shoulder of the case, so if your case headspace is correct, it will trim to the right length.