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20 practical

The flare can happen when you step down too much at once. My process is:
step 1, size in a 223 die and set my shoulder and the neck comes out at .243" with the expander removed
step 2, size in a Redding Comp bushing neck sizing die with a .235" bushing
step 3, size in a CH4D die that has the neck diameter I need for the brass I am sizing. I have 3 different FL 20P dies in total with different neck diameters for the brass I am using

But you can do the steps I do with a 223 bushing die with nearly the same results. Your shoulders (case head to datum) are all over the place. Are you using a neck sizing or FL sizing bushing die? You need to use a FL bushing die.
Yes, redding 223 type s FL bushing die
 
If you're having trouble, maybe try doing 1/2 the neck, turn case 180, and finish.

Check them for fit in your chamber before loading. If they fit, load them and they will iron out.

My chamber neck dia. is .235. I bring the case necks down to fit that with one bushing, then finish with a .226 bushing. I only do half the neck, but I'm doing 20-222, so I've got a much longer neck than you do.

I finish with a pass of a .2035" mandrill to get my final neck diameter. That happened to be the diameter of the Lee Decapper shaft in my Universal Decapping die.

Just be sure your brass isn't thick enough to clamp the bullet in the case when chambered. -- Do you know the neck dimension of your chamber?? Reamer Print? jd
It's a white oak barrel, I took it to the smith for threading and do not have it with me.
 
Which 20 practical die are you using?
Well I went and looked and it appears it’s a Redding 223 die. Came with the rifle so I never paid much attention. Either it’s a busing die or our local smith who built the rifle made the die? ( he did that for a buddy who had a 223wssm ackley built).
 
Update- got dillon case lube (lanolin/alcohol). Feels smoother but no change. The bushing just doesn't make it down the neck that far. The shoulders are being bumped .006.
I guess I'll just load and shoot and hopefully it works out.
 
Have you tried turning the bushing over? Some have a little more radius on one side thats suppose to go down so it doesn't form a donut but necking down can work better depending on the bushing mag.
I neck down with one pass and if it chambers I dont worry about it the first time just don't bump your shoulders back a chit ton.
 
Update- got dillon case lube (lanolin/alcohol). Feels smoother but no change. The bushing just doesn't make it down the neck that far. The shoulders are being bumped .006.
I guess I'll just load and shoot and hopefully it works out.
If you can close the bolt and get good ignition, your chamber will fix them fast... and they will probably shoot decent in the process. YMMV
 
Have you tried turning the bushing over? Some have a little more radius on one side thats suppose to go down so it doesn't form a donut but necking down can work better depending on the bushing mag.
I neck down with one pass and if it chambers I dont worry about it the first time just don't bump your shoulders back a chit ton.
Yes ive flipped it. Do you get early pressure with the "dougnut" around the base of the neck on the first firing?
 
I would do the neck down without the expander/rod(die gutted except for the bushing). Bushing should barely rattle when you shake the die. With a titanium bushing I put the knurled adjusting ring on top of the bushing as a spacer. You need to make sure the case shoulder is tight to the die shoulder, so the case is supported(a neck sizing bushing die will not work for the first die forming). I use a mandrel for inside neck diameter. When I use a .226 bushing, some commercial brass is a little loose on neck tension.
 
I would do the neck down without the expander/rod(die gutted except for the bushing). Bushing should barely rattle when you shake the die. With a titanium bushing I put the knurled adjusting ring on top of the bushing as a spacer. You need to make sure the case shoulder is tight to the die shoulder, so the case is supported(a neck sizing bushing die will not work for the first die forming). I use a mandrel for inside neck diameter. When I use a .226 bushing, some commercial brass is a little loose on neck tension.
This is dead on what I do, including the .226 bushing. Then, after the first firing, I only size 1/2 of the neck. (but mine is 222 brass which has a much longer neck)

I also am seeing some of my older brass showing thin necks/low tension on my mandril. But most of that brass has already endured several firings as 222 cartridges. I'm thinking about getting a .225 bushing just to use on these cases. It is nice when using a mandril, how you can "feel" the tension that your bullet will seat with. jd
 
*Update* *solved*
Dies-
1.) redding 223 FL bushing die with .225, .233, .248 bushings. 2.) Remove 223 decapping rod/expander ball l and replace with part #14206 (.204)
3.) Any brand (I used hornady) 204 ruger neck sizing die with expander.

*Steps to convert 223 to 20p
1.) Size once fired 223 brass with the redding die and .248 bushing.
2.) Size again with .233 bushing
3.) Set up 204 ruger neck die slowly, until it sizes down to the neck/shoulder junction. The expander ball with give the final size.

For once fired 20p cases, just simply insert your .225 bushing and size your brass like any other once fired case.


This has eliminated the "dougnut", or "ring" at the base of the neck which caused hard chambering. The ring is created by bushing dies, which do not size the whole neck. The use of the 204 neck die with the expander ball as the final step, gives a perfect converted 20 practical case.

Yes this is 3 steps, yes some people claim they can do it in less. However I have not gotten it to work in 2 steps.
 
Just food for thought when using a 204 length die for a 223 based application.

A 223 based neck-shoulder is at 1.5573" and a 204R shoulder is at 1.6502"

That implies your 204 die cannot touch the neck-shoulder of a 223 based design. YMMV
 
I'm not understanding this either, I use 223 FL Redding bushing die to neck down 223 brass for my 20 Prac in 1 pass using a .226 bushing and have no problem with anything.
I've necked down alot of brass and never have experienced donuts, necking up different story.
 
I'm not understanding this either, I use 223 FL Redding bushing die to neck down 223 brass for my 20 Prac in 1 pass using a .226 bushing and have no problem with anything.
I've necked down alot of brass and never have experienced donuts, necking up different story.
How many firings do you get? Any split necks?
 
Just food for thought when using a 204 length die for a 223 based application.

A 223 based neck-shoulder is at 1.5573" and a 204R shoulder is at 1.6502"

That implies your 204 die cannot touch the neck-shoulder of a 223 based design. YMMV
That is correct. I does not touch the shoulder
 
I'm not understanding this either, I use 223 FL Redding bushing die to neck down 223 brass for my 20 Prac in 1 pass using a .226 bushing and have no problem with anything.
I've necked down alot of brass and never have experienced donuts, necking up different story.
It crushes the brass every time I do it. I'd love to see a closeup of your neck/shoulder junction after converting.
 
It crushes the brass every time I do it. I'd love to see a closeup of your neck/shoulder junction after converting.
Here you go, notice I put a pretty good chamfer on the outside of the neck.
One on the left is sized down in one pass with a .227 bushing with imperial wax.
On the right is after necked down and shot once.
I dont anneal either untill after there necked down.
 

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