17-222 - Case Forming from .223 Brass

[Oso Polaris]

A while back I bought a Sako L46 in 17-222. I bought some ammunition and used a fired cases to create a Modified Case for use with Hornady OAL Gage and also Sinclair Chamber Gage. The rifle has a Chamber Length of 1.686" and the Neck Diameter is 2.065" (proxy - Neck O.D. on fired case). The project got put on hold and now I am finally able to focus back on it. I am having fun cutting my teeth in Case Forming for both 20VTG and 17-222.

I would like your input on the process (steps, order of activities, and dies/bushings) that I am using. I am pregnant with the equipment on hand. If you are going to recommend that I go search for previous posts/threads then my answer is I already sifted through 20 pages of thread listings using search words "Case Forming" and also "17-222" and "17 Remington". The best was a post involving "17-223". I am asking the question here amongst Saubier because this is a very small caliber and a specialty round. I believe there are more experienced hands on similar calibers here then on Shooters Forum.

Initial Case Preparation to .223/5.56 Once-Fired Brass before the Case Forming Process: Clean, Decap, Debur Flashholes, Swage Primer Pockets, Anneal and then polish outside of necks.

17-222 Case Forming Process from .223/5.56 Donor Brass:
1. Redding 222 Rem. Type-S FL Sizing Die (internal components removed). O.D. of 0.255”.
2. Redding 222 Rem. Type-S FL Sizing Die (.238 bushing) with internals removed.
3. Redding 222 Rem. Type-S FL Sizing Die (.228 bushing) with internals removed.
4. RCBS 17-222 Form Die (vintage) used with the Redding Extended shellholder. O.D. of 0.223”.
5. Redding 222 Rem Type-S FL Sizing Die (.212” Bushing) with internals removed.
6. RCBS 17-222 Trim Die (vintage) used with the Redding Extended shellholder. O.D. of 0.202”.
7. Anneal the Cases, and then polish necks (inside & outside)
8. RCBS 17-222 Rem. FL Sizing Die (vintage) with internal components removed. O.D. of 0.194”.
9. Neck Expander Die to open neck to proper size.
10. Trim to Length, Chamfer Case Mouth (inside and out) - 21st Century’s 3-Way Cutter.
11. Neck Turning to fit chamber - 21st Century Neck Turning gear.
12. Remove the Case Lube.
13. Load & Fire
14. Refine/Master the case forming process and then repeat using new premium brass.

I have tested the process (stopping prior to neck turning) on 50-100 cases. I have noticed that the case reduction between the 17-222 Form Die (0.223") and the 17-222 Trim Die (0.202") is the trouble spot where the case is most likely to form a doughnut. It takes 3-4 hard pulls/back-offs to work the brass through the Trim Die completely. I believe that the amount of reduction is too large taking into account the small neck diameter, thickened case walls and the work hardened brass resulting from the previous reduction steps. To partially mitigate these issues, I plan to add an interim reduction step using a .212 Bushing. I have ordered the bushing and will have to wait a week or so before being able to assess the amount of improvement (reduction in tendency to form doughnuts). I don't mind doing an extra step through the press to achieve a better end-product.

Based on Neck O.D. of fired case, my chamber neck is 0.2065". Unless I am mistaken, this would be considered a generous/loose neck to the point of being considered a No Turn. Please confirm my math/logic - .172" Bullet, .026" neck wall thickness (.013" each side), and .004" clearance (.002" each side) for a total of 0.202". This leaves .004"-.005" of excessive clearance. Depending upon neck wall thickness I can maybe keep the neck walls thicker (0.0015") to use up the excess space and just do a minimal skimming during neck turning.

I have ability to do any of the case trimming and turning operations while the case is sized either at the .20 cal range or the .17 cal range. What are the advantages of doing neck turning while the case is in the .20 cal diameter neck? Does the above data on loose chamber influence the best timing/order for doing the neck turning?

Any and all insight and recommendations are appreciated. Thanks!

[flyrod]

That looks like quite a process you've worked out. If the current concern is donuts and you don't want to ream inside the neck, then you've got to push the metal out and cut if off the outside. When doing this, I've had the best luck necking down to slightly below where I want the diameter to finish, then anneal (this part is important), then expand using a cylindrical mandrel (not a button). This should give you a good straight ID for the neck and push any donuts or inconsistent thickness to the OD. Then you can turn the OD and get nice necks.

[Oso Polaris]

Thank You - those were my thoughts as well. Toward the end of the process I am annealing the formed case then running it through the last FL sizing die to squeeze it down (smaller then final). After the last reduction, I will be using a Neck Expander Mandrel Die to open the entire neck to a uniform ID, which should push all of the irregularities to the outside. After doing this I will then Neck Turn to create a uniform neck wall thickness.

[flyrod]

If you can, I'd try moving the anneal step back one, so that you're annealing just before expanding on the mandrel. This should give you the least amount of spring back. When I do 7mm WSSM I expand on a mandrel in the lathe and turn the neck right then (on the mandrel). This works nicely, but not everyone has a lathe to play with...

[Oso Polaris]

Originally Posted by flyrod

If you can, I'd try moving the anneal step back one, so that you're annealing just before expanding on the mandrel. This should give you the least amount of spring back. When I do 7mm WSSM I expand on a mandrel in the lathe and turn the neck right then (on the mandrel). This works nicely, but not everyone has a lathe to play with...

OK so switch order of Step 7 and Step 8

[camel]

No matter what you do, you are going to get donuts forming where the shoulder/neck junction of the 223 case is sized down to 222 length.

I did a few when I had my 17/222 built, after lots of experimenting I just went and bought some new 222 brass.

What I did to get rid of the donuts was to internally ream the cases out at the 222 stage before sizing down to 17. I also gave them a fine outside turn at this stage. Still got a smaller donut, and had to ream out again at the 17 neck down stage.

Going down in too big a step is always going to be a problem, even when forming my 20/222 cases I had to go down from the original size to 20 in two steps.

[Bill K]

And here I have doing it too easy, I guess. I played around with my 221 FB form/trim die and found by backing the die off and measuring until I had the length need to make 222 Rem cases, instead of going all the way to the base of the die for 221FB, I had a 222 Rem case and just had to trim the length and make the final fireform to the chamber.

[Oso Polaris]

Originally Posted by Bill K

And here I have doing it too easy, I guess. I played around with my 221 FB form/trim die and found by backing the die off and measuring until I had the length need to make 222 Rem cases, instead of going all the way to the base of the die for 221FB, I had a 222 Rem case and just had to trim the length and make the final fireform to the chamber.

Hey Bill --- I am a glutton for punishment and over-engineering things.

Yes, that's how I started out doing the initial neck bump with the 221 FB Form and 221 Trim Die. Luckily, I looked in my drawer and found my little bin marked "17-222", and in there I found the Redding 222 Bushing FL Die and thought," Why not try it." After recently working on forming 20VTG from 223 cases, I was surprised that it only took one pass, clean and easy, through the 222 FL Sizing Die (no guts). The only reason I think this works so smoothly is that bumping back the shoulder from 223 to 222 isn't nearly as extreme as for the Fireball/Vartarg. The 223 shoulder becoming the new 222 neck, and the top 1/8" of 223 case body becoming the new shoulder on the 222 case. All of these areas have thinner wall thickness and don't have as dramatic of a change compared to the Fireball/Vartarg case forming. By comparison the top 3/16" of .223 case body becomes the neck on Fireball/VTG, and the from there to just under the typical case anneal line (call it upper 1/3 of case body) on .223 case becomes the new shoulder on Fireball/VTG

Also, I initially used my Redding 20 Vartarg FL Die (guts removed) to do the next intermediate step reducing the neck down to 0.236". After 50-100 cases, I decided to buy a .238" bushing for use with the 222 Bushing Die so that the shoulder angle doesn't accidentally tweaked, reduce risk of doughnuts and minimize the number of dies I need to install/remove throughout the process.

I have had some other Die/Gear Discoveries (things purchased and then misplaced or forgotten). This is what finally got me committed to building my reloading bench, everything is neatly stacked, visible ad has its dedicated place.

[Bill K]

I guess if you have to tools and all the dies, use them. Nothing wrong with that.

[ray h]

I've read this several times and each time my head hurts. You need a set of Neil Jones bushing. Sure would make your life easier.