Does Anyone Here Anneal Their .300 BO Brass?

RLinNH

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Mar 23, 2019
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I was just not 10 minutes ago going to anneal 292 pieces of .300 BO Brass. I have an Annealeez Machine that has been great for the 2 plus years I have owned it. But when I went to size up the machine for the .300 BO brass, I got worried about melting the sponge wheels seeing as the brass is so short. I am not annealing this brass for accuracy sake. I am annealing this brass to get more life out of it seeing as it is such a pain is the balls to get for the past couple years. Thinking maybe a set of the small sponge wheels are in order here. If you do anneal your .300 BO brass, check in here. And if you do it on an Annealeez machine, LMK if you are using the stock wheels, or if you purchased the small wheels (If they are even existent. I haven't checked yet).
 
Looks like a small case kit is in order for my .300 BO Brass. Still Anxious to know though, is it going to be just me that anneals their .300 BO Brass?
 
I've done it on my bench source. I do adjust the flame up a little higher on the neck so the heat doesn't run far down the body too far.

Never had a problem.
 
Pain in the balls to source? Range pick up 223/5.56. Small chop saw. Cut just behind shoulder. Full length size. Trim to length. About the only thing easier is 6.5 <==> 6 creedmoor.
 
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I anneal fresh converted brass before sizing. I use the annealeaze and wrap the wheels with aluminum tape. Also works for 6br. Helps a lot for that intial sizing
Edit... I am using their small wheel set wrapped for br and blackout.
 
Tag for replies. I bought a set of the small wheels a while back to use for 6.5 Grendel. Have not used them yet. I now am in the process of getting set up for 300 BO. Might do as M4orturnate does and anneal before sizing converted brass.

Off topic, but which 300 BO cutoff jig is best?

Do you guys anneal 300 BO each time before sizing?
 
Tag for replies. I bought a set of the small wheels a while back to use for 6.5 Grendel. Have not used them yet. I now am in the process of getting set up for 300 BO. Might do as M4orturnate does and anneal before sizing converted brass.

Off topic, but which 300 BO cutoff jig is best?

Do you guys anneal 300 BO each time before sizing?
I only do the first time but probably will again sfter the 3rd loading just to keep it semi consistent. Dont use s jig just chop a little below the shoulder
 
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I process a lot of 300 Whisper/Blackout for local shooters because my 1050/110 with a Mark 7 autodrive makes it much easier and faster.

Most people dont ask me to anneal it.

For my own full auto plinking, I do it because I have an AMP and because I can.

For my boltgun 300 ammo, I always do.
 
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I don’t think anyone is claiming you have to anneal when forming 300 Blk from 5.56. You don’t.

But 300 is the same as any other rifle brass, in that if you reload it enough times, you’ll want to anneal it to prevent neck splits and to make neck tension even. Just because it’s a short case doesn’t mean that need magically goes away, but I suspect some of you just haven’t loaded your cases enough times to get to that point.
 
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I treat my 300 BO just like all my other brass . I prep it like my match ammo . Annealing is a huge benefit for many reason . One being consistent neck tension , which leads to consistent accuracy . I shoot it in bolt guns . I guess if it was just blasting ammo for an AR platform not taking the time to anneal would be ok . Another thing to remember if using chopped 556/223 the portion that becomes the new neck/shoulder has not been annealed fully from the start and in some cases thicker/stiffer than factory 300 BO brass. The heat may have run down that far while still being 556/223 but not enough to properly anneal that area .
 
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I anneal, but I convert all of my own from LC brass--I have a virtually unlimited supply of once fired LC from my club after the local SWAT guys finish their training. The annealing makes sizing much more consistent. I don't think I've gotten more than 3 loads on a piece of brass yet--my .300 is my pig hunting gun and I'm always too busy watching the pigs to worry about where my brass is going.

I use an old Lee lead pot and salts to anneal. I made a little stand with 2 posts on it clipped to the correct height to anneal just past the shoulder......once you get the rhythm its easy to have each case in the salts for 7-8 seconds and I get a perfect temper line on each case. I don't have to worry about ruining brass by over-annealing like I did with propane, and results are much more consistent. Just have to be careful not to splash or drip.
 
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I don't think I've gotten more than 3 loads on a piece of brass yet--my .300 is my pig hunting gun and I'm always too busy watching the pigs to worry about where my brass is going.
Brass catcher. Shoot em up and when you get in the truck you unzip and drop it on the floor board to collect at the end of the night.
8462791B-5830-42C7-AD35-0060890BBF63.jpeg
 
Brass catcher. Shoot em up and when you get in the truck you unzip and drop it on the floor board to collect at the end of the night.View attachment 7915278

Which brass catcher are you using?

I've tried Caldwell - junk IMO. Currently using a Brass Goat, which works really well. Only complaints are the bulk, and if pointing the muzzle down sometimes 300 Blk brass can fall out. That zipper style looks less bulky than the Brass Goat, might be worth a try if it works as well.
 
Which brass catcher are you using?

I've tried Caldwell - junk IMO. Currently using a Brass Goat, which works really well. Only complaints are the bulk, and if pointing the muzzle down sometimes 300 Blk brass can fall out. That zipper style looks less bulky than the Brass Goat, might be worth a try if it works as well.
It’s the caldwell. Picatinny and not Velcro mount.
1658291426796.gif
 
It’s the caldwell. Picatinny and not Velcro mount.
View attachment 7915803

Haha no worries. I just ran into too many times where the net was collapsed, so the brass wouldn’t eject properly and caused malfunctions. Or the cage around the net moved away from the receiver and brass came out.

FWIW that Brass Goat is only about $40 on Amazon. Has a catch can that ejects like a magazine to dump your brass. But for forged lowers only.
 
Which brass catcher are you using?

I've tried Caldwell - junk IMO. Currently using a Brass Goat, which works really well. Only complaints are the bulk, and if pointing the muzzle down sometimes 300 Blk brass can fall out. That zipper style looks less bulky than the Brass Goat, might be worth a try if it works as well.
I have a couple of the Caldwell bag type, with the velcro that I usually lend to people shooting beside me at the range if they're hitting me with brass. But my Magwell Mounts Brass Goat is well worth the $40, IMO. Had mine for about a year. Probably will buy another one soon to have a 2nd one.
 
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I have a couple of the Caldwell bag type, with the velcro that I usually lend to people shooting beside me at the range if they're hitting me with brass. But my Magwell Mounts Brass Goat is well worth the $40, IMO. Had mine for about a year. Probably will buy another one soon to have a 2nd one.
I have been using the caldwell bag for a few years with no issues. I have never heard of a Brass Goat, until this thread. I just ordered one.
 
Wheels & Alum tape. ? wasn't there someone seeing if there was a market for wheels made of Alum .?
Someone in this forum was/is in the process of trying to develop aluminum wheels. I got about 1/2 way through the thread and gave up. I am sure that he has an update if you want to read it.
 
I have yet to anneal any of my 300 BLK brass. It's all converted LC brass and I'm working on it's 6th reload of mostly subs. All I do is seat the bullets and give the completed round a light crimp to keep them in place. Never had a issue and I'm working on 1k rounds fired using only a few hundred cases, some hot supers thrown in for hunting and HD zeroing
 
Was just looking at a different thread and this one popped into my feed… I never annealed my 300BLK until pretty recently. Started to get some cases with very loose neck tension, and was going pretty hard on my factory crimp die to compensate.

Some brass was gtg, some not…. I dug deeper and noticed almost all the cases with the loose necks were converted brass; ergo, brass I converted (or bought) when 300BLK was still a pretty new thing 10 or so years ago. They have to be on their 6th (or more) reloading by now.

I just bought a new AGS version 2.0 annealer a few weeks ago and have started running all my 300BLK brass through it after my usual overkill cleaning and prepping process:

i-D6wKqPT.jpg


Think I may need to up my time in the flame a bit more, at about 4-5 seconds right now. I definitely notice the difference when I neck size now. Much smoother as the case runs through the die with the 300 or so cases I’ve annealed so far:

i-PC4kmHb.jpg


Gonna pick up some 750 degree (maybe 650 too) Tempilaq paint, and test some trashed brass (mouth beat to hell, loose primer pockets, etc.) to destruction…get ‘em glowing red on the inside of shoulder and then go past that point. Trying to nail down the right amount of time to fully anneal, without destroying the brass.
 
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Was just looking at a different thread and this one popped into my feed… I never annealed my 300BLK until pretty recently. Started to get some cases with very loose neck tension, and was going pretty hard on my factory crimp die to compensate.

Some brass was gtg, some not…. I dug deeper and noticed almost all the cases with the loose necks were converted brass; ergo, brass I converted (or bought) when 300BLK was still a pretty new thing 10 or so years ago. They have to be on their 6th (or more) reloading by now.

I just bought a new AGS version 2.0 annealer a few weeks ago and have started running all my 300BLK brass through it after my usual overkill cleaning and prepping process:

i-D6wKqPT.jpg


Think I may need to up my time in the flame a bit more, at about 4-5 seconds right now. I definitely notice the difference when I neck size now. Much smoother as the case runs through the die with the 300 or so cases I’ve annealed so far:

i-PC4kmHb.jpg


Gonna pick up some 750 degree (maybe 650 too) Tempilaq paint, and test some trashed brass (mouth beat to hell, loose primer pockets, etc.) to destruction…get ‘em glowing red on the inside of shoulder and then go past that point. Trying to nail down the right amount of time to fully anneal, without destroying the brass.

If you’re going to use Tempilaq, get some 900*. 750 is the minimum to start annealing, not the target.

Or go until they just barely start to glow dull red in a dark room, and keep it set there or back off a hair. Personally I stopped using Tempilaq.
 
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