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20 Practical brass prep and source

Thanks, but IF I have to pay for range brass, our range charges the going rate for scrap brass (by the pound). I think the current cost is around $0.60/lb, but I may be looking at the wrong type of brass. Either way, for the amount I'm looking for, I can probably get it at no cost if I call ahead of time.
I've been getting $1.60/lb for cartridge brass.
 
"correct 20 cal bushing" is the question mark at this point. Don't know what the loaded neck diameter will be until I run the first case through the die with a bushing. Won't be able to seat a bullet until I have the bushing. Thankfully, an AR buys me a little more wiggle room on neck tension, and bushings are cheap so if I'm not quite happy with it, it's not a huge deal to get another bushing.

Can someone refresh my memory; does an S die have an expander ball? I was thinking that it did, but that would negate the benefit of the bushing.

My biggest concern in this process is that reading through the more detailed posts that I've found, it looks like necking down to 20 cal can add some concentricity issues, and that's one thing I'd really like to avoid because I don't really want to invest $$ into gauges to start checking my concentricity. I'd rather spend that money on the tools needed to process the brass correctly and avoid the problem to begin with.
You may have to purchase additional bushings to get the correct tension. While the A/R's are a bit forgiving on neck tension, it is imperative that you have enough. Otherwise, your bullets will slip backwards into the cases a smidge when the round is being loaded into the chamber, and in worse cases, will slip forward when the bolt slams home. You will end up with very erratic pressures and accuracy. You will want a bushing that is at least .003" smaller than a loaded round measurement right at the end of the neck. I use a .001" smaller bushing when shooting 32 grain V-Max bullets as opposed to my load for 40 V-Max and 39 Blitz Kings - which bullets have more contact (and therefor friction) with the necks. I'd purchase the regular steel bushings to start with. They last a long time unless you shoot a lot. Once you know what size worked out best, you can buy the coated bushings when (if) you wear out the steel bushings, if desired.

The "S" dies do have an expander bushing. I pull out my de-cap assembly and spin it in a drill to take it down in diameter with a diamond file so that it does not interfere with my neck sizing. The alternative is to de-cap separately and do away with the button. I use a hand tool (a large tapered awl) to push into the neck to remove any large case mouth dents prior to sizing.

Regarding the concentricity, any time one necks up or down in caliber, there is some funky redistribution of brass in the neck which does cause some concentricity issues. When you fire your formed brass, the pressure will straighten it out for the most part - at least well enough that you can get some pretty accurate ammo out of it. Turning the necks gets rid of most of what remains in the form of brass that got redistributed less than evenly in the neck. But that does not have to be done - and can be something you can do at a later date if you ever are so inclined. I never check concentricity on my ammo. If I find a load that shoots 3/8" MOA, I see no need for doing so - that is accurate enough for my varmint work. And I do know there has to be concentricity issues to some degree - but I don't worry about that. I'm not shooting matches with the rifles.
 
I would at minimum sort by headstamp or weight, LC I sort by year
I do the same thing with LC. There are normally a few years where I only have a handful or two, and those go into a "mix" bag that can be resorted later, or loaded for CQB training and drills.

I'm still not sure what size bushing I will start off with, but my end goal is to have at least 4 thousandths of tension on my loaded rounds. I'll pick a bushing that's probably going to be a bit on the small side to begin with, and if I decide its not the right size, the cost of another bushing is not that big of a deal. The bigger deal for me is the irritation of having to order it and wait a few days for it to arrive. I plan to size a few pieces with and without the expander ball to see what the bushing and expander ball are each doing to the brass, and then measure again with a bullet seated.

Not sure what I will want to do regarding the expander ball and bushing die. I've never given them much consideration to be honest. It's been a while, but I've sat through enough materials classes to understand the basics behind yield strength and what it takes to make material flow. My assumption has always been that the die sizes the neck down to the required diameter, and the expander ball ensures that the neck is still big enough that it only stretches when seating a bullet. That makes me wonder how far a case neck will stretch before the ID actually increases (ie how much neck tension is actually possible).
 
Not sure why you would use an expander with a bushing die, unless you are using brass with different neck thicknesses or your bushing is slightly small(producing too tight of neck). Since I decap separately and use mandrel to control the ID of the neck, I size with the die gutted. Whether a bushing die(I don't have a bunch of bushings for different brass) or standard FL die. Mainly I just wanted to use equipment I already had and not over work the brass.
 
On some of my 17 and 20 cal stuff that uses Lapua, turned brass I make I use no expander or mandrel bushing only to the NK tension I want
 
I do the same thing with LC. There are normally a few years where I only have a handful or two, and those go into a "mix" bag that can be resorted later, or loaded for CQB training and drills.

I'm still not sure what size bushing I will start off with, but my end goal is to have at least 4 thousandths of tension on my loaded rounds. I'll pick a bushing that's probably going to be a bit on the small side to begin with, and if I decide its not the right size, the cost of another bushing is not that big of a deal. The bigger deal for me is the irritation of having to order it and wait a few days for it to arrive. I plan to size a few pieces with and without the expander ball to see what the bushing and expander ball are each doing to the brass, and then measure again with a bullet seated.

Not sure what I will want to do regarding the expander ball and bushing die. I've never given them much consideration to be honest. It's been a while, but I've sat through enough materials classes to understand the basics behind yield strength and what it takes to make material flow. My assumption has always been that the die sizes the neck down to the required diameter, and the expander ball ensures that the neck is still big enough that it only stretches when seating a bullet. That makes me wonder how far a case neck will stretch before the ID actually increases (ie how much neck tension is actually possible).
If you don't have a ball micrometer, you can pick up a cheap one on Amazon for the price of a single bushing. Measure the thickness of your brass. Take that measurement and double it, then add the measurement of .203.5 (diameter of a lot of .20 caliber bullets. If your brass is .012" thick x 2 =.024" + .203.5 =.229.5. Deduct .003 to take the brass down for tension = .226.5. In this case, I'd go with a .226 bushing to start. This will get you close to where you will likely end up - if any changes need to be made. Best thing to do when checking tension is to size up a few dummy cartridges, wait a few days, then load them with bullets only. This is because the brass often "springs back" just a bit - and can be measurably different over a 24-hour period, depending on whether the brass was annealed prior to sizing. Put them in your magazine and let the bolt strip them off the magazine and let bolt slam home. Eject them one by one and re-measure the overall length from brass base to bullet tip. if the measurement changed, you need more tension.
 
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Any concerns that the tight closure could cause a feed issues on an AR? I'm guessing not because your bolt gun probably has a tighter headspace. Probably worth mentioning is that I plan on using my small base sizing die when I initially size it. I'm also kicking around the idea of setting my Dillion up with the case trimmer and trimming them all before doing anything else. I doubt that the brass would actually need it, but might as get it out of the way while its still in its 223/556 form so I don't have to buy extra tools to do it as a 20 cal manually.
With my AR 20 P I use new star line brass and trim as needed after the first firing. I don’t have my notes handy but seems like I had to push the shoulders back a little to get consistent bolt lock up. Letting the bolt slam forward from locked open. I am sizing mine in three steps using a Hornady progressive press. Check run out between steps and you may not have to size in three steps. E
 
I keep it simple, its a 223 datum length, I set the die to size for a 223 Lyman ammo checker lower step -0.001(.001 below the step) for the AR barrel in the winter. Than all loads chamber without FA, and extract with no issues in below zero temps.
 
Very good information for bolt gun and AR's in this 3 page thread.
I just wish the information was consistent. I've gotten everything from new LC brass, trimmed and neck turned, annealed and sized in 3 steps to using a random mix of range brass that's been run through a gutted die and then finished with a single pass through a bushing die. Don't get me wrong, the information was VERY helpful, even if it wasn't consistent. To me, it means that I can go the cheap and easy route and probably get 1/2 moa groups from my AR, but if I'm not happy, or I just want to see how accurate it can be, there are several other (relatively simple and inexpensive) steps I can add that could make a measurable difference on the target. It would be easy to read through all 3 pages and feel like I hadn't actually learned anything, but the truth seems to be that it can be as easy or as complicated as you want it to be depending on the level of accuracy I require, and even going the cheap and easy route, the accuracy is still likely to be really good.
 
One thing you gotta understand that the steps in processing brass and reloading is not written in stone. Some people just get there a different way, you can complicate it or not its up to the individual and I guarantee you will tweak the way you get to the process along the way. Theres alot of over thinking sometimes, pick a process and roll with it good bad or indifferent and tweak along the way as you see fit.
 
Exactly. I'm one of those who tends to over think things a lot of times. Since this is for a gas gun, I'm going to force myself to start off at the simplest possible process and use that as a base line. Its encouraging to know that there are at least a few people who are ONLY doing the minimum amount of work and are still getting really good results. Near as I can tell, if I follow my original plan, and add one or two chamfering steps to it, that will be a good starting point for me.
 
Definitely different ways to approach the process. I went at it , 223 body and a 20 cal neck. With the AR part of sizing needing some tweaking.
 
I have two 20 Practicals an AR and a RPR. I have used any and every piece of 223 brass that I’ve had laying around or picked up. I use a Dillon 550 to size and then neck the cases down in two steps and then trim them. It’s simple as that. Both rifles will group within a dime at 100 yards and drop Prarie Dogs easily out to 300 yards.
 

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