Tutorial of How to convert 223 cases to 20 Practical

[jepp2]

purchase my AR upper in good used condition, and it came with the Redding 223 REM B/FL 5T bushing die, and also the 233, 226 and 225 bushings, plus a Competition Series 204 Ruger seating die. The barrel is a White Oak Armament 24" bull barrel, and it was all for $400

That was a steal. I get over 5,000 rounds through my WOA barrels before I see the accuracy start to fade.

 

[Coyotefurharvester]

If you have 0.004+ neck clearance in your chamber, turning brass probably only costing you time and a bushing purchase. If wanting to play with neck wall thickness, than a mandrel will save you money and push donuts out.

 

[Rick300]

I currently use a Redding S die with bushings for determining neck tension in my 20P cases. I'm thinking my next step is to skim turn some of the necks of once-shot (in my 20P) after I re-size them with my 225 bushing, as that's the only way I currently have to make the necks any smaller with the 20P cases.

If you are planning to turn necks then you have to be able to size the whole neck. A bushing will leave the bottom portion of the neck unsized and if you try to turn them after sizing you will have a VERY thin neck diameter at the base of the neck shoulder junction. I had to determine the amount of neck turning before I reduced the brass to .20 cal as I don't have a non bushing die. LC cases have thin necks anyway so a 75 - 80% cleanup is all you need. YMMV

 

[TheCZKid]

X2

I neck down Lapua 222 brass for my 20-222 and Lapua 22-250 brass for my 20-250 and I don't turn the necks on either one. With the Lapua brass unless you have a tight neck situation due to the reamer used there is no need to turn necks.

I checked the neck thickness of my LC brass last night with calipers, it appeared to be pretty consistent overall. I think you're right. I don't want to add extra work on all my cases with no real net gain.

 

[jepp2]

I checked the neck thickness of my LC brass last night with calipers

Don't take this as criticism, but calipers are very inaccurate for checking neck wall thickness. Takes a good ball micrometer that reads to 0.0001" to really know what you have. (and someone that can correctly use it). The only 20P necks I have turned were on brass made from Lapua where I was less than 0.002" than the chamber neck with my loaded rounds.

 

[TheCZKid]

Don't take this as criticism, but calipers are very inaccurate for checking neck wall thickness. Takes a good ball micrometer that reads to 0.0001" to really know what you have. (and someone that can correctly use it). The only 20P necks I have turned were on brass made from Lapua where I was less than 0.002" than the chamber neck with my loaded rounds.

I understand and appreciate your note. I don't have a spherical caliper, I was trying to find one that would fit into a 17 Hornet neck, so I could check ALL my case necks. As far as I know, nobody makes one that will fit that slim of a neck. I'm sure some precision model might exist for $300+, but ones I can afford aren't available to fit. I have just tried to carefully use my existing calipers to check neck thickness, at the same depth from rim, flat to the inside and outside surfaces, to at least to get a pretty good idea of variance in thickness. With some practice I have been able to do a decent job of checking my 17 Hornet cases, before and after turning. I used the same process with the final formed LC cases and they seem pretty consistent. Given the limits of using my calipers, I at least have a fairly close idea.

 

[searcher]

If you wanna turn neck by all means do it, I run alot of LC brass and it is good brass.
Most 20 Prac reamers have a chamber .232 nk its what mine is and I believe without looking my loaded rounds are .228
If turning necks are an accuracy gain is what your after not sure if that goal is gonna be achieved on a 20 prac but thats something you may have to try yourself I just never found it much of a gain.

My buddies and I have all been shooting the .20 Practical for years and on many barrels - have found that turning necks to 85% clean metal did more for accuracy on this little cartridge than it ever did for my 6PPc's, Dasher, 6 BRs, etc.. It is not that turning didn't help those calibers - just that the smaller the neck - the more .002" or .003" in variation means. Of any necks ever turned, the biggest gains were found in turning my .17 Hornet necks. But any time one is forming a neck down from another caliber - that brass just doesn't flow uniformly. So it almost always ends up worse than it started. It doesn't perform miracles - just improves the situation. If I can get another 3/16" MOA in accuracy - I'll turn necks. Others would say whatever they are getting out of an A/R is "good enough". As you say - it depends on what accuracy one is after.

 

[TheCZKid]

My buddies and I have all been shooting the .20 Practical for years and on many barrels - have found that turning necks to 85% clean metal did more for accuracy on this little cartridge than it ever did for my 6PPc's, Dasher, 6 BRs, etc.. It is not that turning didn't help those calibers - just that the smaller the neck - the more .002" or .003" in variation means. Of any necks ever turned, the biggest gains were found in turning my .17 Hornet necks. But any time one is forming a neck down from another caliber - that brass just doesn't flow uniformly. So it almost always ends up worse than it started. It doesn't perform miracles - just improves the situation. If I can get another 3/16" MOA in accuracy - I'll turn necks. Others would say whatever they are getting out of an A/R is "good enough". As you say - it depends on what accuracy one is after.

I am going to try turning some necks on the .20 Practical. First annealing all my cases, then sizing, and maybe annealing again... then turning. I purchased a 224 bushing from Midway a couple days ago, won't be here for a bit, but I figure that will replace the 225 bushing for un-turned neck brass to keep the same neck tension.

 

[searcher]

Don't take this as criticism, but calipers are very inaccurate for checking neck wall thickness. Takes a good ball micrometer that reads to 0.0001" to really know what you have. (and someone that can correctly use it). The only 20P necks I have turned were on brass made from Lapua where I was less than 0.002" than the chamber neck with my loaded rounds.

I am going to try turning some necks on the .20 Practical. First annealing all my cases, then sizing, and maybe annealing again... then turning. I purchased a 224 bushing from Midway a couple days ago, won't be here for a bit, but I figure that will replace the 225 bushing for un-turned neck brass to keep the same neck tension.

I use a .222" bushing on my 32 grain bullets and a .223" with my 39 and 40 grain bullets. Of course - my necks may be turned a bit thinner. This is what I need to not have any bullet slippage in the cases when the rounds load.

 

[Bugger Picker1]

I'm just getting back to working on loads for my 20 Practical, since 2018. I was reviewing my process of making 20P brass from Lake City cases. Today I was sizing my cases in stages, and noticed the concentricity was good from first FL die, then went way off with first bushing. So I called Redding today to see if I was doing something wrong. They said if I'm getting 5 thousandths of runout that's really good, and should not have any noticeable affect on accuracy.
Some cases were going from about 1 thousandth to 5 to 8 thousandths. Tonight I found a method for making my cases average 2 thousandths of concentricity when final. So, I wrote myself a "how to" page, so I could review it in the future, if I forgot again.

I'm not sure how well others first converted cases are turning out, and am curious if my methods are similar to others. Here's my info I wrote, curious what you think of my "How-To Tutorial" list for myself. Thought it might be helpful for new 20 Practical reloaders too.

How to make Concentric 20 P Cases, with your first conversion cases.

Prepare cases by de-capping the primers, cleaning the cases, primer pocked uniforming, and flash-hole deburring.

1. First size once shot cases in a Full-Length Small Base sizing die, with the Expander Rod removed.

2. With my RCBS FL SB die it takes the neck diameter from outside diameter of .2520” to .2375”, and I only let the shoulder get pushed back to 1.575” or less approximately, not below 1.573” base to shoulder datum, with Hornady G240 case comparator. The concentricity from a Full Length die should be about 1 thousandth.

3. Next, with Redding S Die put in 233 bushing with the lock-nut from the expander rod on top as a spacer. Set die to NOT “bump” or set back the shoulder for this first bushing sizing, or at least not to the final shoulder bump you want for the final dimension. The concentricity might not be very good, from .002” to .008” runout.

4. In Redding die, install 225 or desired final bushing size stamping facing down, and then set the die to bump the shoulder back to 1.567” base to shoulder with AR barrel (or to your desired final dimension for your chamber). With the bushing and the bump together in the final sizing, this should bring the concentricity to .001 to .004 on average. The shoulder bump and bushing sizing both together on final sizing seems to really help to bring the neck into concentricity with the case on the final sizing. I even had the .008 runout necks go back to about .002 to .004 using this method.

5. After it’s sized, then trim necks to OAL of 1.750" or 1.755” for case, and chamfer & deburr the necks. Clean sizing lube off exterior, run a brush through the necks, and you’re ready to load.

Annealing might be a good idea after your cases are freshly converted, or at least after fired 2 or 3 times.

Neck Turning:
After the brass is shot and fire-formed to your chamber, it will be more concentric. This would be a good time to turn the necks. The sizing down of the neck from 223 to 20P tends to make the final thickness of the neck uneven, and a skim turn to bring it to uniform thickness will help in accuracy.

Keep in mind, if you turn the necks, it will make change the outside diameter of the neck, and lessen how much your bushing ends up sizing your necks, and neck tension will be less. If you use a bolt action rifle the neck tension can be as low as one to two thousandths. If you are using an AR upper you will need more neck tension to keep the bullets from sliding forward when they chamber, so you might need a smaller bushing. In an AR four thousandths or more neck tension might be minimal to be safe. So, a final bushing might be 224, or what you determine is correct for your application.

We are all different and have different goals. The brass for my first 6 BR back in 1998 I made from Used Remming 7 MM BR I wanted to save money. I didn't know the first thing about Quality brass, annealing used cases. Neck turning or any of that stuff. The rifle shot 1.5 groups and I thought I had reinvented the wheel. One day I was shooting at the 100 yard line with concrete benches and a benchrest shooter that chambered his on barrels asked me what was wrong with my rifle. Talk about letting the wind out of my sails! he had a bore scope and looked down my barrel and said it looked good. Then he looked at my ammo and said here is your problem. I thought my shiny cases looked good. He said your brass is junk! Back then Br brass was not easy to come by and expensive. He mic. on my case necks and they had up to .004 difference in thickness and case to case over all width about the same. He digs a 220 Russian case out of the bottom of his tool box and hands it to me and says this brand of brass is the best and they are making 6 BR brass now so you don't need to neck it down and it will shoot better. I found some and bought it. instantly I am under an inch. I finally got my shooting and loading down to 5/8. I said all of that to say I never shoot used brass that wasn't mine when it was new. A barrel and having it it threaded to a wild cat is not cheap plus the dies and or bushings more expense I have a 20 Practical and use 223 bushing dies to reload with but use a Wilson 20-223 seater to seat bullets. I bought 100 Hornady 223 brass because I could not get Lapua 223 at the time. The necks were .0035 thick on one side and 0.012 on the other. Still junk in a no turn neck. My opinion is the best brass that you can buy is the best investment you can make. Necking Lapua brass down if I don't go to many calibers it will clean up at a .0015 or less. The only Sage Rat rifle I have that doesn't use Lapua brass is a 17 Ackley Hornet because at the time I built it they don't make 22 Hornet brass. Now they do and with in the next few months I plan to acquire some and test it.