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popper
04-14-2014, 12:16 PM
Setting up the Lee dies for the new 300BO. Set up is good, close to min. for the case gauge but wait - have to pogo to extract. There is now a sharp ridge at the shoulder, sharpie marked case shows the interference. I don't really want a neck separation. Factory ammo is NOT at min in the case gauge. I can grind the die to set the shoulder back farther, below min. HS. Is that needed? Real question - I don't want jams & slam fires from the 2 boxes of jacketed factory subs. I will pull the FP and try the factory before going to the range. Any ideas are welcome. I don't intend to have the chamber reamed. Oh, other than the factory Rem, the brass is mixed range PU - chopped with a dremel, trimmed & inspected.

KYShooter73
04-14-2014, 01:03 PM
What brand shellholder are you using? Im at work right now, but Ill try to do some measuring when I get home to see if there is a difference using RCBS or Lee.

xacex
04-14-2014, 01:10 PM
Who's barrel are you using Popper? I did have one that was tight from the factory I attribute to the Melonite coating. It took at least 1000 rounds to finally not be so tight. But, I did not get sharp ridge on the shoulder. They may have not finish reamed it.
I had some issues getting the lee dies set. They wanted to be all the way down before the stroke of the press to work and size propper. With them set as low as they will go plus a quarter turn I get max now in the case gauge. They also seemed to need a break in period.
What are you sizing your boolits to? I have two blackout that will take them all the way up to .311, and one( the one I mentioned earlier) that has a hard time taking .310 at times. Requires mortaring the rifle to get them unstuck.

xacex
04-14-2014, 01:24 PM
Also, some types of cases are not good for blackout. The neck is to thick. I will look for the list to avoid.

here is the list for cases to convert, and ones to avoid. That could also be what you are seeing. The thick part of the shoulder smacking the chamber and trying to size down. (fat headspace)

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=88599&sid=888d468fb008c408d8b2d770cff72693

popper
04-14-2014, 02:15 PM
Lee 3 die set. I've had to grind the die length on others. Using the 31-165C with ONLY the GC shank in the shoulder - yea - it fits, sized 0.310.
This is mixed brass, PPU seems to work fine expanded with the 30 M die. M4 feedramp is a problem so I got to find another mag to mess with.

It looks like the neck area is a bit long and scuffs some brass back (~ .010" wide) at the neck/shoulder junction. For now I guess I get out the grinder & see if that solves the problem.
I only sized 6 cases, chambered 2. Looks like it stretched the neck/shoulder area when chambered.

xacex
04-14-2014, 03:05 PM
Let us know if you get it dialed. I know I am maxed out with my shell holder.

Shiloh
04-14-2014, 03:11 PM
I'll have to ask some of the shooters. They make there own brass out of 5.56x45 brass. Splits are trimmed off. Not sure if they anneal first.

Shiloh

armorer59
04-14-2014, 03:26 PM
I know it's a tick short, but I use .221 Rem Fireball for .300 cases. The necks don't wind up thick and therefore do not require reaming. My dies are Redding with an RCBS shell holder.

GRUMPA
04-14-2014, 03:34 PM
I don't know which gauges your using, and I take material off the shell holder and not the die for any adjustments. If your using range finds for the brass expect problems in brass thickness at the neck, that's always a concern.

Look at the drawing I have on the first post of this thread.
http://castboolits.gunloads.com/showthread.php?150466-300-AAC-Blackout-Brass-(Price-Change)-1-13-14

Most of the DOMESTIC cases will be OK to use and IF PPU brass works for you your doing OK.

dh2
04-14-2014, 03:39 PM
Is the problem with all brass or with one head stamp. I think you have found a case that is thicker than others .
try sorting you brass and see if the problem is with one brand of case
I do not bother with annealing my .300 AAC Blaskout cases just sort the headstamps

fastfire
04-14-2014, 03:55 PM
I'll have to ask some of the shooters. They make there own brass out of 5.56x45 brass. Splits are trimmed off. Not sure if they anneal first.

Shiloh


I cut first Anneal, deburr then size.
Anneal before sizing to lessen spring back, makes sizing easer and lengthen the life of the case.

Jupiter7
04-14-2014, 03:57 PM
I've never annealed any either. I don't convert any foreign brass any more, a few slipped in once and none would chamber. There is supposed to be a sharp ridge where the neck meets shoulder, there is a double step. I've read of issues with lee 300blk dies not setting should all way back.

popper
04-14-2014, 04:47 PM
I've read of issues with lee 300blk dies not setting should all way back.
I think you nailed it Jupiter7

Jailer
04-14-2014, 07:32 PM
I wouldn't use PPU brass for 300 Black out. Stick to domestic brass as Grumpa has stated.

KYShooter73
04-14-2014, 08:09 PM
I had some issues getting the lee dies set. They wanted to be all the way down before the stroke of the press to work and size propper. With them set as low as they will go plus a quarter turn I get max now in the case gauge.

True that. I may be miss thinking this, but if your goal is to bump the shoulder back a few thousandth more than your die will allow, wouldn't it be easier to remove a bit of material from the top of your shellholder?

xacex
04-14-2014, 08:19 PM
True that. I may be miss thinking this, but if your goal is to bump the shoulder back a few thousandth more than your die will allow, wouldn't it be easier to remove a bit of material from the top of your shellholder?

Yes sir! And I may still do that because like I say I am just...there, barely. I did notice when I put them in the Loadmaster I did not have the same problem. Shell plate must be thinner. But, I like to prep my brass with the other press that has the individual shell holders. It would be nice to play around with the shoulder length a bit more than I can now. I have many variables I am still playing with so I just have not got around to that one specifically. As is I have been producing functional ammo in 300 BO for several years now without playing with that aspect. But, that is another variable to accuracy beyond functionality.

KYShooter73
04-14-2014, 08:24 PM
Slow thinker and slow typer. Grumpa beat me to that one, but of course he the the Blackout Jedi Master.

GRUMPA
04-14-2014, 09:48 PM
Ill say something about the LEE dies right off, they're cheaper for a reason. The sizing die itself wont take the case to SAAMI specs on there own. The reason is LEE made them this way for a reason, so it won't over work the brass. The expander rod will get smaller faster than the other die companies that make 300BO dies. If you check the expander diameter when you first get it and run about 5-10K cases through it the diameter gets smaller.

The only way to make LEE dies work for forming 300BO is to make them fit by altering a few things. It can be done but you have to be mechanically inclined and have somewhat specialized tools for the job.

I've altered every 1 of my dies in some fashion to my standards of doing things, and when I form the brass it goes through 3 different sizing dies before it's done, I do things to eliminate problems once they get shipped. There's other small details when it comes to this but that's another story.

GRUMPA
04-14-2014, 09:52 PM
You got that right! I bought my brass from him, and its beauteous! So far I have attempted to make (1) case, and it chambered just fine. I'm using RCBS small base dies with taper crimper. I have some 1x 5.56/223 brass, but of various headstamps. I'm not sure that its gonna be worth my time to make cases...

I alter just a few head stamps, so far I've done all domestic brass at 1 time or another, I have to change the die settings by each individual head stamp because they don't react the same. I use an indicator when these are formed and check every 50th piece during the run and it's a nightmare trying to size mixed head stamps to the point I've sent brass back that was sent to me for conversion.