300 blk out

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Any of the major gun stuff emporiums such as Midway, Sinclair International and others should carry dies. They may be out of stock but inventories are finally beginning to catch up after the recent panic.

Accurate Arms has load data for 300 BLK. See here...

http://www.accuratepowder.com/wp-content/uploads/2010/09/WP_LoadSpec_7-2-13.pdf

Hornady #9 has 300 Whisper/300 BLK data but I do not remember if it includes heavy bullets.
 
If you are loading for an AR, I highly suggest a set of rcbs SB dies. I had lee dies and had a lot of chambering problems. You can change out the standard expander ball(.306") with a .308 expander ball if you decide to shoot .310-.311" cast bullets in the future.

I also highly suggest sticking to one headstamp of brass. A lot of commercial brass varies in wall thickness which can lead to problems. There is someone(par0thead) in the buy+sell offering bulk lake city 223 brass for dirt cheap. it was under $140 for 2500 pieces shipped and all but two pieces were lake city.

get a harbor freight mini chop saw, a 300 blackout cutoff jig( i bought one made by squirreldaddy, works well for me) and a little crow WFT trimmer and you are ready to bust out the brass fast!

I referenced people's published load data from 300blktalk.com when working up my loads.
 
1. I found AA1680 works well for subsonic loads with 220 grain bullets. IMR 4227 didn't cycle my AR dependably.

2. Loads for the 300 Whisper are the same as for 300 Blackout. One of my Hornady manuals had loads for it.

3. Cabela's had bags of ready to load 300 Blackout brass made from military 223 Brass. I have no complaints as to the quality thereof.
 
I have a Hornady and a Forster sizer for 300 BLK, and they both work well. I am seating with a Redding die with a micrometer top which is handy when you load several bullets in the same caliber and when I crimp it is with an RCBS seater that has a crimp ledge halfway between a roll crimp and a taper crimp. They call it a taper crimp.

"Modified" roll crimp on a 125 Gr SST in 300 BLK.
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Grumulkin said:
I found AA1680 works well for subsonic loads with 220 grain bullets. IMR 4227 didn't cycle my AR dependably.
I think reliability of bolt cycling and last round bolt lock back depend on the gas tube length also.

I am using 16" barrel with pistol gas tube and like A1680 and H4198 but also have W296/H110 on hand to test next - https://www.youtube.com/watch?v=6ku1OPZpyn0

Got a lot of powder/load info from here - http://www.300blktalk.com/forum/viewtopic.php?t=86656

Hodgdon has load data for 220/230 gr bullet (and various forum data) which I referenced to use for 230 gr powder coated lead bullets (subsonic loads) provided by blarby for testing. I am hoping to test 170 gr powder coated bullets next (supersonic) IF I could get a sample from blarby. ;)
 
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I have recorded my 300 blackout loading journey here. As a matter of fact it is time for me to update the site with additional load data and tools I use to enjoy reloading 300 blackout. I had no idea it was going to turn into what I have today and get so many visitors.
http://www.dayattherange.com/?page_id=3460

I get a lot of questions via email, which proves interesting as I do not consider my self to be an expert on the 300 Blackout round far from it but I do not mind helping if I can.

The one thing I will say is learn from my experiences and save some money :) Meaning if you are going to load lead bullets forget the larger size expanding balls etc, this is not meant to poopoo on anyone's suggestions I just found they do not work as well with lead. The main reason is lead bullets from different manufacturers are sized differently, for this reason I have found the Lyman M die to work best. But please get the right one I got mine from Midway, and there are two different dies for 30 caliber rounds.
Product #: 153391 Lyman #: 7349004 UPC #: 011516790040

You can get it a few cent to 1 buck cheaper from other places but I found Midway was in stock.

Please read the instructions for using the M Die it is a two step expander and this die with the exact same powder charge with Missouri Bullet Company 245gr lead bullets went from 4inch shot gun like pattern groups very unpredictable. To under 1inch at 50 yards and 1.275 at 100 yards. As a matter of fact I shot my 300 blackout very little at 100 yards because of the frustration from very large 4 to 6 inch groups if you can all it that. I thought it was my scope at first, come to find out it was just lead bullets that were the problem. My jacketed supersonic loads grouped great. The MBC bullets are sized to .309 and are great quality. I have tried Palmetto Projectiles also. I found with lead the problem with accuracy was due to the case not being expanded enough and shaving the base of the bullets as well as squeezing the bullets down from .309 and .310 all the way down to .307 even when utilizing the lee rifle expander. It was the Lyman M Die that solved this issue.

The other tool to get is a Sheridan case guage http://www.sheridanengineering.com/index-1.htm I had finished rounds that would fit in the Wilson guage but not chamber in 3 different rifles. Once you understand what the Wilson case guage is -- a guage for checking cone to head for overall length then you realize why. Cone to head are Wilson's words not mine as I called them about my problem, and the gentleman on the phone explained it that way. This guage is only to make sure you have trimmed your brass to the right length. The Sheridan guage is a chamber guage built to saami spec to mimic the 300 blackout chamber, and will also tell you if your length is right. This was an invaluable tool to me.

One last thing, mindset. Do not think the 300 blackout is some magical round that will shoot lights out without following all the steps you do with normal rifle rounds. Most important I have found is case separation. This is another thing that tightened up my groups, I separate 308 and 223 brass by headstamp and understanding case volume to get the best accuracy, but with 300 I was just blasting away and disappointed at my results. Well if you are using cut down 223 brass it needs to be separated the same way due to case thickness. I say case separation is even more important if you are using cut/trimmed back 223 brass, that far down the brass thickness varies a lot from brand to brand affecting case volume which most definitely affects accuracy.

Sorry for such a long post, 300 blackout has become one of my favorites and I just want to share my endeavors and pitfalls to help others.

Mr. Revolverguy
 
Thanks!

So true that consistency in reloading practice improves accuracy. I was told the same about "inherent inaccuracy of round" when I switched match caliber to 40S&W from 9mm/45ACP. When I got smaller shot groups than theirs, I asked for explanation and they chalked it up to "fluke". Well, I can't call 20 years of accuracy "fluke". :rolleyes::D

Have you shot powder/coated lead bullets in .300 BLK?
 
BDS yes sir all my load data is on the page.

I have received a few emails today asking if I could make it short and easy on the tools I use to load 300BLKout.

I typically don't like to do this, with reloading it is not something you want to skim over.

As easy as I can make it --- Pictures :)

I have also found that 221 brass resized is more accurate than cut 223 brass. I hope to get some new 300 factory brass and compare, 223 cut, 221 resized and 300 new.

Anyway here are my tools.
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Be careful looking for 221 brass and telling guys you are going to size it out to 300 blackout. It is so hard to come by they just might ban you from the range or kidnap your kids. 221 fireball has a cult like following :).

Please read the article bds I tell what you need and how to neck size it up. You will need 2 different sizer expanders and redding will send them to you very cheaply.
 
Will check out the info.

I will just tell them I am saving up the brass for a .221 Fireball rifle. ;):D

Seriously, I have plenty of .223/5.56 brass on hand so I will likely use cut brass for bulk of my .300 BLK reloadings. But will certainly test .221 brass to see how much more accuracy I can squeeze out for more "premium" .300 BLK loads.
 
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