20 Practical - Runout Issues, Advice?

[TheCZKid]

For about a year been trying to decide if I wanted to create a 20 Practical AR upper, and finally found a deal on an upper on Armslist I couldn't pass up. What I got was a lightly used upper with a White Oak Armament 24" bull barrel, in an upper with hand-guard with BCG, etc. It also came with the Redding 223 B/FL Type S die with 233 and 226 bushings, 223 decapping rod and 204 decapping rod, plus the Redding Competition 204 seating die, all for $400, very happy with it.
I'm using LC brass, decapped and swaged, ultrasonic cleaned.
So to form the brass I use my Forster .223 FL die without the expander rod for first sizing. Seems to have good concentricity after that first sizing, under .002, normally .001 average.
Next I use the Redding S die with .233 bushing, and they stay concentric to .003 and normally .002 or less.
Last step is with the .226 bushing using the .204 rod expander ball, and only about 60% to 65% or so are .003 or under. The remainder are mostly .004 say 18%, .005 about 12%, and maybe 10% are over .006.
When I use the bushings I tighten the top screw part till it touches the bushing, then back off slightly, so if I shake the die the bushing is able to move a little, rattle slightly.

I'm going to run some tests with good loads I know my gun likes with say 5 rounds each using the .003 brass, 5 with the .004 brass, 5 with .005 and 5 with the worst offenders, see if the groups open up as specific concentricity gets worse.

But my concern is making MORE of my sized brass be in the .002 category, as I can get with my Forster dies and LC brass for my .223 AR's.

 

[jepp2]

I'm going to run some tests with good loads I know my gun likes with say 5 rounds each using the .003 brass, 5 with the .004 brass, 5 with .005 and 5 with the worst offenders, see if the groups open up as specific concentricity gets worse.

I think this is an excellent approach. I have spent a lot of effort and $ to reduce both case neck and bullet runout, and to date I can't say it has made any difference in my group size. But what the heck, it makes me feel better.

For brass conversion, I take it in 3 steps like you do, just use different dies. And my case neck runout after this is always 0.001" or less.
1. Redding 223 die with a smaller neck w/o expander (I just pick the stock 223 die that has the smallest neck diameter)
2. Redding Competition neck sizing die with a Whidden .235" bushing (I get half the runout with Whidden bushings vs. Redding)
3. CH4D 20-223 FL sizing die that I honed the neck to 0.226" and I reset the expander so it exits the case neck "just" as the neck leaves the neck portion of the die.

I use a Redding Competition 223 bullet seating die, but am quite unhappy with the runout (most in the 3-5 thousandths runout range) if I seat the bullet in a single step. If I seat the bullet in 3 steps, rotating the case ~120 degrees per step, about all are around 0.002" runout. I talked to John Whidden to find out what his bullet seating dies would provide in the way of runout, and they would be better than the Redding Comp seating die, but he asked me why I was interested. Subsequently I picked up a used Whidden 223 seating die, and indeed the runout is less than the Redding Comp seating die.

 

[hogpatrol]

My 2¢. If you are looking for good numbers on runout, you'd be better served by using other than LC brass.

 

[jepp2]

you'd be better served by using other than LC brass.

Now that is a statement I do have targets to prove. When I use Lapua brass for my 20P and 20 Bobcat, the accuracy is better. Case necks on Lapua brass are much more uniform in thickness (and thicker).

 

[GAnderson]

What is your bullet run out on a loaded cartridge?
From your post, it appears that you are checking neck run out after each successive "necking" down and run out gets worse...then you introduce the expander ball in the final process...this may be one contributing factor to an increase in your run out...that and the fact that you are not neck turning...the brass has to go somewhere and if the neck wall thickness isn't consistent to begin with, it will progressively get worse as you squeeze it down. Also, why use the expander ball? This seems counter productive to using bushings to achieve the desired neck tension.
I think variation in neck wall thickness and the expander ball are the main factors...would be interested to know what your bullet run out ends up being...it may be good enough that you won't have to worry about it.
One other thing, you might try "floating" the die too...not just floating the bushing.

Just some thoughts.

Gene

 

[nmkid]

I also use 3 steps in necking down my brass with Redding bushing dies. I do not own a concentricity tool but, my 20 Practical gives me groups in the 1's and 2's every time I take it to the range. As for me, I have quit obsessing so much about the things that take us down the, 'rabbit hole' of accuracy. But, that's the beauty about this hobby. We each have the power to decide how deep we want to get into it.

 

[Prose]

I use LC for my 20VT and turning necks after expanding is mandatory. Fully prepped LC brass gives me very low runout and groups in the .2's. Annealing between forming steps is also mandatory.

 

[TheCZKid]

What is your bullet run out on a loaded cartridge?
From your post, it appears that you are checking neck run out after each successive "necking" down and run out gets worse...then you introduce the expander ball in the final process...this may be one contributing factor to an increase in your run out...that and the fact that you are not neck turning...the brass has to go somewhere and if the neck wall thickness isn't consistent to begin with, it will progressively get worse as you squeeze it down. Also, why use the expander ball? This seems counter productive to using bushings to achieve the desired neck tension.
I think variation in neck wall thickness and the expander ball are the main factors...would be interested to know what your bullet run out ends up being...it may be good enough that you won't have to worry about it.
One other thing, you might try "floating" the die too...not just floating the bushing.

Just some thoughts.

Gene

Good input on these replies, appreciate it! Starting at the selection of brass, I have successfully prepped a few thousand pieces of LC with my Forster dies for .223 use in my AR's and had them average .001 to .002 runout. The consistency of brass in weight and uniformity seems better than most, but have also prepped quite a few Hornady, Winchester Remington and my favorite Norma. Norma is the MOST consistent in quality in what I've gotten so far, and I don't plan on purchasing Lapua brass, as I just don't have the money to do so. I have found the brass I use at popular shooting areas near by, and, unfortunately I already prepped the brass for .223 Before I got my 20 Practical. LC brass seems a good choice, but I think I'll try to neck turn and see if that solves the issue. My runout with bullets seated seems to stay same as runout of the original case.

From a "Practical" standpoint, I just shot 3 groups (same load) of five rounds, with brass that had concentricity of .002/3, .004 and .005, and all 3 groups were within .02" of each other, so the concentricity did not appear to have any discernible effect on group size. My 22-250 is affected adversely by out of round brass, runout on that makes a huge difference, but I'm new to the 20P upper and not sure from experience.

Regarding using the expander ball on the last stage, I'll try the bullet tension without using the 204 expander and see how that feels. Have not tried it yet to be honest. Might help.
About "floating" the die in addition to the bushing, don't know how to do that, except maybe buying the Forster press that has the dies float. The Forster dies to use the decapping rod / expander with a rubber washer at top, so it floats the rod, and Redding is rigid, so that might be causing some runout issues.

 

[TheCZKid]

I use LC for my 20VT and turning necks after expanding is mandatory. Fully prepped LC brass gives me very low runout and groups in the .2's. Annealing between forming steps is also mandatory.

I've never heard of people annealing between the sizing down steps as mandatory, but understand why it might be a good idea. I liked the "practical" part of just sizing the brass and... Whala! load it.

I just tried sizing down 5 pieces of Norma brass, same issues. 1st Forster 223 die without expander ball, stayed at .001 runout. 2nd stage Redding die floating using 233 bushing, runout went to .002 to .004 in this stage. Last sized with 226 bushing floating with NO 204 expander, results were .002 to .005 runout, most .0035 to .004. Not good. Not sure what to change, perhaps calling Redding and asking advice in using their dies with their bushings and how to NOT create runout issues.

 

[boltfluter]

You might try floating the die as recommended as well. An O ring under the die works great for this. Good luck.

Paul

 

[GAnderson]

CZ, another question...are the run out numbers you are quoting Total indicated run out? If so, in theory then you are only "half" off of center from your measurements. Also, did you check run out on the bullet after seating a bullet? If so, did they exhibit the same or worse run out numbers? Your variations could be outside diameter only...unlikely, but possible.
Finally, have you re-sized any of the pieces of brass after firing them? If so, what is the run out on them? if you shoot them after forming, they might not be as bad once they are formed to your chamber.

 

[TheCZKid]

CZ, another question...are the run out numbers you are quoting Total indicated run out? If so, in theory then you are only "half" off of center from your measurements. Also, did you check run out on the bullet after seating a bullet? If so, did they exhibit the same or worse run out numbers? Your variations could be outside diameter only...unlikely, but possible.
Finally, have you re-sized any of the pieces of brass after firing them? If so, what is the run out on them? if you shoot them after forming, they might not be as bad once they are formed to your chamber.

I was mainly measuring the brass, checked the final (at ogive) of a couple loaded rounds and they seemed to be same as what the brass was, example .004 same after loading. I'm using the RCBS Case Master. I'm using Hornady 32 and 40 V-Max bullets, probably pretty concentric, but I've mainly been interested in controlling the runout of the brass at the neck.

After firing them my initial batches (ones that started as .002/3) seem to all be in the .001 to .002 range after firing, and after sizing them with last 226 bushing, using the 204 expander, they are staying in that range or .001 normally. These once shot and re-sized are very nice.
I just checked the test brass I shot yesterday, and the .002/3 without re-sizing are about .001, the .004 are in the .0015/2 range, and even the .005 batch are all about .0015/.002 range, so they have formed to be more concentric from firing.

 

[GAnderson]

I was mainly measuring the brass, checked the final (at ogive) of a couple loaded rounds and they seemed to be same as what the brass was, example .004 same after loading. I'm using the RCBS Case Master. I'm using Hornady 32 and 40 V-Max bullets, probably pretty concentric, but I've mainly been interested in controlling the runout of the brass at the neck.

After firing them my initial batches (ones that started as .002/3) seem to all be in the .001 to .002 range after firing, and after sizing them with last 226 bushing, using the 204 expander, they are staying in that range or .001 normally. These once shot and re-sized are very nice.
I just checked the test brass I shot yesterday, and the .002/3 without re-sizing are about .001, the .004 are in the .0015/2 range, and even the .005 batch are all about .0015/.002 range, so they have formed to be more concentric from firing.

I don't think I would worry about it too much then if after firing they are in the ball park. I think the run out is just from the sizing down process...you won't control that very much unless you skim turn the necks.
I vote that you load them, shoot them and not worry about it.

 

[TheCZKid]

I don't think I would worry about it too much then if after firing they are in the ball park. I think the run out is just from the sizing down process...you won't control that very much unless you skim turn the necks.
I vote that you load them, shoot them and not worry about it.

I agree, like I said earlier I shot the tests with the .002/3, .004 and .005 and the groups were pretty much the same size. I have enough LC brass (a 5 gallon bucket full) that I can just size them and take the best and sell the bad ones for brass metal.

 

[TheCZKid]

I don't think I would worry about it too much then if after firing they are in the ball park. I think the run out is just from the sizing down process...you won't control that very much unless you skim turn the necks.
I vote that you load them, shoot them and not worry about it.

I contacted Redding customer service regarding the runout, and they agree too... here's a paste of their reply:
"I would first say that I don't consider runout/concentricity until after the case has been fired as a 20 Practical. Keep in mind you are altering the case neck (in diameter) and brass does not like to be manipulated and therefore wont likely be very concentric after the necking down process.
Once the brass has been fired as 20 Practical, I then begin looking at runout. At that point I will mark the high spot of a 20 Practical fired case, size that case and then see where the high spot is at that point. If the high spot is still in the same location it points to the case. If the high spot is in a different location on the case we can then look at other things that may be contributing."

 

[TheCZKid]

What is your bullet run out on a loaded cartridge?
From your post, it appears that you are checking neck run out after each successive "necking" down and run out gets worse...then you introduce the expander ball in the final process...this may be one contributing factor to an increase in your run out...that and the fact that you are not neck turning...the brass has to go somewhere and if the neck wall thickness isn't consistent to begin with, it will progressively get worse as you squeeze it down. Also, why use the expander ball? This seems counter productive to using bushings to achieve the desired neck tension.
I think variation in neck wall thickness and the expander ball are the main factors...would be interested to know what your bullet run out ends up being...it may be good enough that you won't have to worry about it.
One other thing, you might try "floating" the die too...not just floating the bushing.

Just some thoughts.

Gene

I've shot a decent amount now using the first sized brass, and after I size the once fired in 20P the cases at the neck are averaging .001 or less to .002 concentricity, and bullet runout is averaging from .0005 to .0025 using those once-shot cases. I did shoot some .004 cases with a known good load along side .002 brass, and the groups were about 1/10th inch larger.

 

[nmkid]

On a different note...Have you tried H-335 with the 40 gr. Hornady's?

 

[Dusty Stevens]

After moving that much brass you need to fireform it and going down to a 20 will wildly show any neck inconsistencies. When going down in caliber i really recommend neck turning and annealing. Dont even worry about runout or trimming (unless the case exceeds max length) until theyve been formed.

 

[TheCZKid]

On a different note...Have you tried H-335 with the 40 gr. Hornady's?

I just tried one load of H335 25.3 grains, got 3694 fps and .58" group. I've not gone back to it yet, as I wanted to stick with the IMR 8208, find a place it grouped well, and then verify what seating depth seemed best first, then maybe test out some optional powders. I've got a lot of H335, use it for my .223, so it's one option I'd like to explore.

 

[TheCZKid]

After moving that much brass you need to fire-form it and going down to a 20 will wildly show any neck inconsistencies. When going down in caliber i really recommend neck turning and annealing. Don't even worry about runout or trimming (unless the case exceeds max length) until they've been formed.

I've been progressing along the road in reloading over the last 5 years, and keep adding on more steps in the process to achieve better loads. Early on I did mostly pistol loads, then added .223 for my AR's, and recently got a 22-250 with bolt action, so started looking at seating depth more closely. In looking at my .308 brass for the AR-10 I realized concentricity was an issue (I hadn't gotten my RCBS Case Master yet, had no clue my brass was all over the place). So I got a Hornady neck turner, and mandrels for the calibers I already had, now need to get one for .20 caliber. I've not really used the neck turner yet, just tested it once on some CBC .308 brass that was really out of round. Recently added uniforming my primer pockets to the steps I do.
So, I'll have to gain that skill, of using that neck turner.
And I've never annealed cases yet, so that's another new step I'll have to figure out how to do. I recently got a Hornady Anneal Kit from a friend, haven't tried it yet either, it uses bits you use in a drill motor with cups sized for various calibers and spin them over heat source... I've heard of the method using trays with water and having the tops above, heating the necks with a torch. Any recommendations you like please let me know. Thanks!