Converting. 223 casings to 300blk

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golfindia
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Re: Converting. 223 casings to 300blk

Post by golfindia » Tue Nov 14, 2017 10:57 am

Cut off a case below the shoulder and measure wall thickness. If it's more than ~0.013" they will cause problems.

I've made thousands and thousands of 300blk brass with Lee dies. Make 5-10 rounds. Put them in your gun. If they chamber, shoot them. Then proceed to make more.

I quit using anything other than Lake City brass for 300blk.

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Re: Converting. 223 casings to 300blk

Post by Boolit_Head » Tue Nov 14, 2017 10:03 pm

If you are not trimming before you resize you may be running out of room in the die. That could explain the crushing you are seeing.

Ditto on the Lake City for me too.

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plant.one
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Re: Converting. 223 casings to 300blk

Post by plant.one » Mon Nov 20, 2017 11:51 am

Rick.nicholson66 wrote:I'm using lee single stage press and lee dies and Lyman gauge.

ok... so first and foremost - the results with using lee dies to form brass over the years has been mixed, at best. some folks have a set that do it no problem, others expierence nothing but frustration. the latter being the most common IIRC. feel free to use the search and you'll find it. most folks are using something other than LEE to form their brass and LEE explicitly says on their website that these are resizing dies and NOT forming dies. they work great for resizing fired cases though so dont abandon them :)

2nd - i will echo everyone else here - use lake city brass. its cheap, plentiful, and works perfectly for conversion due to neck wall thickness.
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Re: Converting. 223 casings to 300blk

Post by rlandry6 » Fri Jan 26, 2018 9:23 am

You don't need to resize the .223 brass before cutting off the necks. You have to resize after trimming to length. The less you work the brass the better. I second the non-use of Lee dies. I have a drawer full of them and have gone to Dillon, RCBS, and Redding with no regrets.
Be sure your sizing die is of the full length, small base variety. Even though the case may fit in the gauge, it may not feed well in semi-autos. The SB die sizes a couple of thousandths smaller.
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r.tenorio671
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Re: Converting. 223 casings to 300blk

Post by r.tenorio671 » Sat Jan 27, 2018 5:37 pm

....depending on how much free time you have, it may be simpler to just purchase pre-made brass from some of the sources providing those service / products on this forum. I personally use John Bowman's product = http://www.carolinabrass.net/

...I also have everything necessary to "roll my own" and did so when I first got into the 300BO game...because I had no choice, LOL.

A couple of things I've "learned" :

I use a "concocted lube of +90% rubbing alcohol and pure lanolin in a 1:10 ratio mix, least costly, works best!

1. A Sheridan Engineering SLOTTED case gauge is indespenisble. Allows for proper setting of dies, determines if problems are with shoulder bump, case trim length, bullet ogive shape -vs- selected seating depth, etc. IMHO, the best investment to save time, frustration and produce better ammo.

2. Full Length-Small Base (FL-SB) dies are best to start with, just a few dollars more but eliminate the potential for chambering/extracting issues. The RCBS AR Series dies are probably the most economical and do the job EXTREMELY well, to include forming of converted brass. If you also load .223/5.56 and already have a FL-SB set of dies for .223/5.56, you can just use that die for the sizing followed by your Lee 300BLK die. Using the .223/5.56 sizing die first will get the case web back down to SAAMI spec and when followed by the Lee 300BLK die it will set your shoulder bump.

3. When I do convert cases, I run .223/5.56 cases thru a Lee Universal Decapper followed by an old RCBS FL-SB .223 sizer without the decapping rod then the Lee 300BLK die without the decapping rod in. The now "formed" cases I will cut down on the little chop saw. This method allows me to get a more consistent trim length and less work for the chop saw as the diameter it has to cut thru is less. I do this in "batch mode", i.e., no less than a couple hundred cases. Afterwards a quick tumble in SS pin wet tumbler to get it all clean of brass shavings and has the benefit of doing a good "deburring". After drying, final run thru my RCBS FL-SB 300BLK dies to get rid of any "spring-back" from the initial forming and set my final shoulder bump followed by the final trim to length with my WFT-2 trimmer. It's critical to do the final trim AFTER the final shoulder bump for the consistency. Then the last tumble in SS pins to clean off lube and ensure primer pockets are REALLY cleaned out, store away after drying for loading day.

If it isn't apparent, I use a progressive press (Lee LoadMaster) so the process goes pretty quick as I have separate tool heads with the dies already in place. I just swap the tool heads depending on the process I'm doing, forming or loading.

here are links to some older posts discussing converting brass:
viewtopic.php?f=141&t=89739&start=10
viewtopic.php?f=141&t=91636
viewtopic.php?f=141&t=92956

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Re: Converting. 223 casings to 300blk

Post by bearcatrp » Thu Feb 15, 2018 12:13 pm

Unless your annealing the brass after you cut these down from 5.56, have found you will have issues. Your cutting off the annealed part of the 5.56 brass. Just went through this. My loads with cut brass was crapola at 100 yards. Bought new Hornady 300BO brass and now shooting sub MOA @100 yards with same load I used with the cut brass. Was shooting Hornady 110 V-Max out of a 16 inch barrel. Until I anneal my cut brass, bagged and put away.

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plant.one
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Re: Converting. 223 casings to 300blk

Post by plant.one » Thu Feb 15, 2018 1:03 pm

bearcatrp wrote:Unless your annealing the brass after you cut these down from 5.56, have found you will have issues.
not so much.


i'm not saying you dont have a problem with your brass - but if annealing were REQUIRED to properly form this brass, we'd know it a LOOOOONG time ago. it would be part of the "making 300 blk brass 101" tutorial EVERYWHERE... and would likely have been the deathnail to the caliber instead of allowing it to grow and settle into mainstream like it has.



lots of brass thats reformed 5.56 -> 300 blk is produced without annealing - tens and tens of thousands of pieces of the stuff.



i know, i've purchased a few K of it myself, although mine has since been done after i got my annealer. not that it *needed* it, but i wanted it done.
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Re: Converting. 223 casings to 300blk

Post by dellet » Thu Feb 15, 2018 1:09 pm

plant.one wrote:
bearcatrp wrote:Unless your annealing the brass after you cut these down from 5.56, have found you will have issues.
not so much.


i'm not saying you dont have a problem with your brass - but if annealing were REQUIRED to properly form this brass, we'd know it a LOOOOONG time ago. it would be part of the "making 300 blk brass 101" tutorial EVERYWHERE... and would likely have been the deathnail to the caliber instead of allowing it to grow and settle into mainstream like it has.



lots of brass thats reformed 5.56 -> 300 blk is produced without annealing - tens and tens of thousands of pieces of the stuff.



i know, i've purchased a few K of it myself, although mine has since been done after i got my annealer. not that it *needed* it, but i wanted it done.
Let's see.
A cartridge that has developed a reputation for poor accuracy, or tough to tune.
A lot of people using backyard converted brass.

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Re: Converting. 223 casings to 300blk

Post by bearcatrp » Thu Feb 15, 2018 6:58 pm

You guys who have shot both don't see a difference? I was lucky to get 4 inch groups with cut brass. The new Hornady brass got me sub MOA @100 yards. That's a huge difference. Have to admit though I changed crimping, instead of a light crimp with LFC die, I used a roll crimp using a rcbs die. Did it as another step. But still stand by my statement from what I haven't seen.

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Re: Converting. 223 casings to 300blk

Post by dellet » Thu Feb 15, 2018 8:52 pm

bearcatrp wrote:You guys who have shot both don't see a difference? I was lucky to get 4 inch groups with cut brass. The new Hornady brass got me sub MOA @100 yards. That's a huge difference. Have to admit though I changed crimping, instead of a light crimp with LFC die, I used a roll crimp using a rcbs die. Did it as another step. But still stand by my statement from what I haven't seen.
Good brass will make a poor bullet and or rifle look good. Bad brass will make good rifle or bullet look bad.

Look at the results Bob The Nailer has been getting with that Rainier bullet. Certifiable uses converted brass and has very good results. He anneals it and then double strikes it to make sure the shoulders stay put.

I won't sat that you won't have problems with 300 headstamped brass, I won't say you can't make converted work.

I will say that much of the poor results and reviews of the cartridge out there are probably in large part do to crappy converted mixed brass, that gave crappy mixed neck tension and wide velocity swings.
300 Blackout, not just for sub-sonics.

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