Home Forums Hunting & Shooting Ask The Gunwriters Size twice?

Lately I have been sizing a case, turning it about 180* and sizing it again. After doing so then running the case through the trimmer there is minimal if any wobble. Have not really been able to see a difference in groups but need to do further testing. It's a simple step, takes seconds and seems to eliminate the occasional wobbly case in the trimmer.

I have read multiple times on here how a straight case is paramount to accuracy. This seems to be a simple insurance policy.

Anyone else do this? Waste of time? Additional brass wear & tear?

Put your dial indicator on the case after it's fired, after it's sized...see if your press or dies are imparting an error.
Maybe when you get your tax refund get a Forster Co-Ax. Maybe get some Lee or Redding dies too.

Please elaborate on what sizing it again entails.

A Forster press isn't a necessity for loading straight cartridges.

I stand corrected, cancel the Forster...get a Lee Loader Classic.

I believe those actually do well in the concentricity department.

A tax refund? What is that? There's a place where I send a big check each year but they never give any of it back.........(insert sarcasm font)

I've been double sizing 6ARC and 222Rem. I use a RCBS Partner press and RCBS .222Rem Dies and Hornady Dies for the 6ARC. I use Imperial sizing wax and dry neck lube. I use the dies as designed with the primer extractor pin and expander ball attached. Pretty much the same system for the last 40 years except sizing twice seems to make a little straighter ammo. I have a concentricity gauge somewhere. Will dig it out and verify.

Brass trimming after sizing on a Hornady trimmer where the case spins around a fixed mandrel. I'd say 1 in 30 or so will have a little wobble sizing one time. That ratio goes to around 1 in 50 sizing twice. Probably more of an issue with the brass (Starline) than the dies.

If you have to size it twice, there is something really wrong with your equipment. It may just be an out of spec expander ball. I always check to be sure those are dead center in the die. I also polish the hell out of them, and make sure they are adjusted properly. It's also wise to adjust your dies, so they produce minimal runout. Mathman can help with that procedure. But going back to the expander, I adjust it so the decapping pin just barely pushes the primer out. It does not have to extend out of the die 3/4", like I see them come from the factory. Most times it's all in making sure everything is adjusted properly. I run regular run of the mill RCBS dies, and they produce sub .003" TIR with just about every cartridge I load for. I do use a concentricity gauge to check that my dies are set up perfectly though.


Running straight ammo is only part of the equation, but it's easy to make right. Might as well learn how to do it. Even if you've been loading for 40 years..

So you're pushing it into the die, pulling it out over the ball, pushing it back in over the ball all the way into the die, and pulling it out over the ball again?

Centershot, There are lots more savvy guys than me to advise...but, offhand, I'd say you are dealing with the symptom! of non concentric cases...rather than just doing the detective work one time to find out where the problem arises. So if you read John Barsness' tips on this problem, he'll walk you through the the best and most logical progression of things you can do to eliminate the problem at it's root. Double sizing is working for you now, but it's cutting your brass life, in half maybe. And you need to anneal more frequently, brass work hardens very rapidly. Find out which step of your reloading process is introducing the error, by actual measurement with a borrowed concentricity checker (or build your own from vee blocks and a dial indicator and magnets from Harbor Freight)
You may discover it's more than one thing, stacking errors they call it, expander ball mis alignment, shellholder bias, funky lock ring on the die? Also you can just go 'quick and dirty' just 'float' everything. Don't use your die lock ring...remove the shellholder snap ring retainer...don't use the locknut on the expander decapper stem...let everything find it's own center as the cartridge enters the die.
Just sayin'. I'd bet my life you don't have bad chambers on your rifles, your tools are causing it.

Yes with a half twist between the two. The second time over is a much easier process.

Got the idea watching one of Eric Cortinas videos where a shooter actually sized a case 3 or 4 times.

If I was getting a weird runout on every case I could see the die(s) being the problem. But, it's not every case more like 3-5%. Not talking about a crazy amount here - barely visible when actually looking for it in the trimmer. Entirely possible that this is considered 'straight' by many.

Was he sizing it three or four times with a conventional FL die?

IMO you are overworking your brass, and checking runout by observing trimmer wobble is "interesting" to say the least.

Yes. The case he did that on was for a test of some sort. For large lots of match ammo he was using something else.

Next time you are sizing cases, just spin one 180* and run the ram up again. Tell me what you feel. I think the shoulders are set more consistently and the necks are pulled straighter. I have reloaded some 6ARC brass over 10 times with no issues. The .222Rem will easily go that many reloads. If I can get 10 reloads per case I feel like I got my money's worth.

I was not 'checking runout' with the trimmer, but that is where the runout was noticed.

I have a concentricity gauge and have never had ammo with more than .003-.005 TIR so I have not used it in a long time.

Seems to me if you size each case two times your gonna be over working the case neck's.

First. If you aren't using a runout gauge how can you tell for sure your cases are bad? Maybe the other tools you are using are bad.

Anyway the only way I can tell is to either roll a loaded round, on a known perfect surface and there aren't many of those around. You can see really bad runout yes. But minor stuff the gauge is the way to go to know whats what for sure.

When it counts, I use only Redding FL bushing dies. I hate pulling necks over an expander. Yes you can polish your expanders but you are changing neck tension as you do. And the outside sizing with a bushing induces less measured error in our tests than dragging over an expander.

Next thing with bushings you can play with neck tension and thats a factor in really good ammo.

The only place I double anything is half seating and then rotate and finish seating. It helps with cheaper dies. I just use good ones for match stuff.

10 times loaded brass means you have sized it 20 times... thats pretty good life actually. No way I"d do that but then again when its important I anneal every 3-5 shots anyway.