interesting sizer findings.

[farmboy]

After being gone from home so much in the last few years I'm getting back to handloading instead of reloading.
I'm running a 280 A.I. and finally am just starting to make it run right. While contemplating quality of my loads, run out especially, and what is right and wrong with them, got to just playing with a few cases and saw something that surprised me.
Equipment-RCBS rockchucker, Hornady New Demension die set, Nosler 280 A.I. brass 1-2 times fired, imperial lube, RCBS concentricity indicator.
As I was checking out the runout on fired, sized and loaded cases there was a surprising amount of them showing runout of .001(didn't think would happen with ordinary FL sizer with expander) and some that went .004-.005. About 90%(?) of the fire as well as sized cases showed runout of .001-.0015. I picked 7 fired cases to play with. They ranged in runout .0015-.005. at no time did runout increase upon sizing. I used a liberal amount of imperial on the inside of the necks. Cases with the largest runout improved after sizing. I took the cases with largest runout and sized them again, 2 cases were sent through a 3rd time. The end result was all cases ended <.0015 runout.
I haven't believed much in sizers with expander plugs and was considering my best options when all this happened. The extra working of the brass isn't good but it is starting to get me to thinking again.

 

[BoydAllen]

Just for grins, try this. Take one of your high runout fired cases, lube it, run it into the die all the way, and then back it out to a point where you can easily turn the case, but the expander is not yet in the neck, and turn the case 90 degrees, and then run the case back in the sizer. Do it two more times, and the last time, slowly pull the expander through the neck, and then measure the case for runout. Let us know how it works. You may note that this reduces the working of the brass considerably, since you will only be expanding one time.

 

[farmboy]

Thanks for the idea Boyd! Have found your insights to be quite useful.
I've gotten lazy and tried to take shortcuts before. They will bite me every time. I bought the Nosler brass (based on positive past experience in other cals) and used them as is out of the box, without taking proper followup steps.

 

[BoydAllen]

Glad that some of what I have written has proved useful. Let us know what happens when you try what I have suggested, on at least a dozen or so cases. While you are at it. measure your cases before and after sizing, at the shoulder, and .3 above the head, and then do the same thing to your sized cases. Let us know about how much smaller sizing makes your cases at these two points. The more you reduce the diameter of the body of a case during sizing, the more effect body wall thickness runout has on how straight your cases are. Also, are you accurately measuring shoulder bump when you set up your FL die?

 

[Nomad47]

One more thing you could try is letting the expander ball 'float'. ie, don't tighten the lock nut.

 

[jonbearman]

I agree with boyd and dont forget to lube the necks before pulling them over an expander button.Boyd,when are you going to write a book about advanced loading as most of us really like when you give advice.I would buy the book in a heartbeat.

 

[BoydAllen]

Thanks Jon,
But I think that I will write it here, one post at a time ;-) The only reason that I do, is because it is fun trying to figure out the problems, and the people are rewarding to work with. Besides, it isn't all teach. I learn a lot, reading of others' experiences.
Boyd

 

[farmboy]

further runout tests:
found 2 high runout cases and took some lower runout cases and did as Boyd suggested-excellent results. ended up making several turns and had runout of .001 or less.

measurements at shoulder and web per instruction: shoulder reduction .004-.005; web reduction .003-.004 these measurements included moderate pressure loads and cases that were loaded too hot.

headspace: headspace on rifle was set short to match brass. FL die will not give any shoulder bump even when set to touching shell holder. Measurement taken with Stoney Point guages. Headspace measurement taken on cases grows .002 when cases are sized. The cases that were too hot were .002 longer than moderate pressure cases after sizing. low-moderate priced digital caliper used for case measurements, consistant results.

Believe I need to send some fired cases off and have a FL die made to match my brass and chamber, thinking this would be a better solution than maching the bottom of my current sizer. For me bushing dies are not an option. My bullet choice sets too deep in the case to risk dognut formation.

Have been reading this and another forum for several years and should know better than some of this.
Thank you to the folks that have spent considerable time and $$ for sharing the insight and helping me bring my head into the sunlight.

 

[BoydAllen]

Thanks for getting back to us on this. It is fun working with someone who is a quick study. For future projects, I think that you may want to think about starting with a regular production bushing FL die, and if well used brass in the caliber that you want (near the end of its useful life, so that work hardening and spring back are maximized) is available, size some of the brass with your die, and then measure the brass, and order a reamer that gives you the body clearances that you want. Just don't set it up too close, or you will run into a tight bolt sooner than you would have otherwise. A thousandth at the shoulder, and one and a half or two at the bottom should be OK for a hunting rifle. On the shoulder bump thing, one of the things that can be done, is to turn a little off of the top of a shell holder, being careful to note the situation in some way, perhaps by marking it in some way. Because some of us shoot PPC cases many times, and they can work harden so that their spring back will not allow them to be bumped with the regular setup, it is common for shell holders to be cut down. I have one that has been cut down .013 (If I remember correctly) It was done as follows. A friend, who has a lathe, closed the jaws of his three jaw chuck and tool a very light cut on the end of the jaws, to even them up, and then opened them a little and tightened the bottom flange of the shell holder between them, with the underside of the top firmly against the tips of the jaws. Then he took light cuts off of the face of the shell holder until he had taken off the amount that I wanted. If I remember correctly, he used the bottom of his dial calipers to measure the thickness as he progressed. Shell holders are not expensive, and they are not hardened, so cutting them does not present a problem. One advantage of having your own reamer, that I forgot to mention, is that for a rifle that sees a lot of use, requiring barrel replacement from time to time, your dies will continue to be a good fit. Otherwise you will have to stay with the same smith, and hope that his is the same the next time that you need a barrel. Just a thought....When I first started planning for my 6PPC, the first thing that I did was to buy a reamer. In that case, I knew that Harrell's Precision made dies that would fit what I was buying so I did not have to work from sized brass. But for any other caliber, that he does not make dies for, I would.

 

[farmboy]

FWIW

I copied this reply from Dave Manson from another websight (LRH)

Here is what Dave Manson of Manson Reamers had to say:

QUOTE

From the reamer/headspace gage maker's point of view, SAAMI standardization of the 280 Ackley Improved has created problems. Mostly, it's a matter of making sure folks are informed about the change, proper fireforming--if they want to go this route--and which ammo to use in which chamber.

Ackley's intent, with rimless, shouldered cases, was to headspace the improved chamber so that the un-improved parent cartridge could be loaded and safely fired in it--the parent round was held between the breechface and the neck/ shoulder junction of the improved chamber. He advised that the breech-face-to-neck/shoulder junction in improved chambers be held some.004" to .006" shorter than in the parent chamber. Traditionally we, and other reamer makers, have done this, grinding reamers with a MINIMAL RADIUS at the N/S junction for more positive headspacing during fireforming.

Nosler/SAAMI shortened the traditional 280 AI headspace another .014". Additionally, the radius at the N/S junction was specified at .060" +.025". This was likely done because it's very difficult to form 40-degree shoulders with small radii--they're supplying fully formed ammunition, remember.

What does this mean for the owner of a 280 AI?

First, if you have one headspaced the traditional way, don't buy Nosler ammo unless you want to see evidence of excess headspace and risk case separation--its shoulder location guarantees at least .014" excessive headspace. When you need new cases, fireform them from 280 Remington brass.

Second, if you have a SAAMI-spec chamber, you can buy Nosler ammo OR fireform 280 Remington. The N/S junction on the SAAMI chamber IS .014" closer to the breech face, but the .060" radius at this points provides a little more room to accomodate 280 Rem ammo. You may feel a little resistance as you turn down the bolt handle, but it will go and the case will be held securely during fireforming.

Finally, re-loading. Don't use dies made to the old spec to re-size cases fired in SAAMI-spec chambers. The few re-size dies I checked that were made to the "old" spec would not reach the shoulder of a case fired in the SAAMI chamber.

You CAN use SAAMI-spec dies to re-size cases fired in old-spec chambers, but be sure to set the die so it barely touches the shoulder of the fired case. DO NOT set the die so it bumps the shellholder when the ram is up--you'll introduce excess headspace or crush the case.

There are different versions of the 280 AI out there, so this commentary doesn't apply to everyone. If anyone has questions about his specific rifle, I'm willing to try to answer them.

Dave Manson
1-810-953-0732

 

[farmboy]

Next I'll have to learn to drive again. Shooting skills have seriously decayed.

I do need to remember that this all is a systems approach: shooter, ammo choices, gun, intended use etc. These choices need to match up.

My way of saying thankyou is to pay attention to what is being said

 

[BoydAllen]

One way to do a rough gauging of how much longer a chamber is than a formed case or gauge is to apply layers of Scotch (sp?) tape to the back of the case or gauge, and try them in the chamber till there is a snug fit.

 

[farmboy]

confident in brass-chamber headspace fit. It seems that facing off the shell holder will be the best short term fix for headspace issues. In a month or so I'll check into having a sizer made to fit, probably Hornady or Forester as I don't think I can't afford the Neil Jones dies. It doesn't seem right to size the shoulder and web area of the cases so much.

 

[Clod-NC]

Hi Farmboy,hi all

Just read the whole thread through;very informative,excellent,bravo again Boyd!!!!Farmboy,you can also check RCBS for custom sizing dies,if you have a print of your reamer send it to them,they'll probably make it for you at a very reasonable price,and needless to say their customer service is beyond compare,I did it for a 6.5x57 imp.30° that D Manson agreed on making a reamer for,and they said they could do it,so don't pass them by,their sizers are as good as any in my opinion..Of course,their lead time will be what you can generally expect at the moment,but,do we have an alternative?Good luck with it then.
Claude

 

[Nomad47]

Farmboy, in the meantime you could place a shim in the shellholder under the case. A .002 or .003 flat feeler gauge would work.

 

[Shynloco]

Just for grins, try this. Take one of your high runout fired cases, lube it, run it into the die all the way, and then back it out to a point where you can easily turn the case, but the expander is not yet in the neck, and turn the case 90 degrees, and then run the case back in the sizer. Do it two more times, and the last time, slowly pull the expander through the neck, and then measure the case for runout. Let us know how it works. You may note that this reduces the working of the brass considerably, since you will only be expanding one time.

Boyd,
Since you've started class, is that method unique to the 280AI or something that works equally as well on other calibers? Personally, I've gotten away from using the standard expander ball in my dies and use expander mandrels in all my reloads that have eliminated issues mentioned in the original post - excessive runout. But your method certainly intrigues me to say the least as I've never heard of or seen that done to correct what may be believed to be bad casings/bent or nonconcentric necks caused during manufacturering of the casings. But as usual, my hats off to ya for helping some of us students who have learned to pay attention when the teacher speaks. Thx!

Alex

 

[farmboy]

Claude
Thanks for the heads up. Somewhere down the road I'll be talking to some folks on this. I'll have to use some one willing to work with fired cases, I have some set aside now for this purpose. Reamer print is unavailable.

Bill
Great thought. It was starting to hit me also. For awhile now it seems my mind is slipping to the point I could plan my own surprise party. Now if I can remember where my feeler guages are@#$%^

Shynloco
I use Lee collet dies for all other calibers with great success. Just haven't done it with this one yet.

 

[BoydAllen]

Thanks,
My thought was that he could do that with the equipment that he has. Like you I have worked with using an expander mandrel in place of the expander ball, when I am stuck with using a one piece full piece die, and have also found that using the mandrel gives better results. Another option, for unturned necks, is to use a two stage sizing process, sizing first with a Lee Collet die, and then using a body die, set for the proper amount of bump. That combination can give really good results, but I hear that these days the collet die may need to be detailed a bit from the factory.
Boyd

 

[Clod-NC]

Hi again Farmboy and all

No prob Farmboy,you're welcome,if you don't have a print of your chamber reamer then make a cast(I reckon this must be a pain in the neck,but then again you wanna go best don't you...)and then send it alongside your request....Boyd,thanks for reassuring me in my 2 stage sizing approach,I've read that same thing from you a while back and it did actually comfort me in the fact that if you recommended it,I couldn't be wrong ...And it sure helps against runnout;I also gave a thought to that 4 stage 360° full sizing gig you mention but thought it would overwork the brass and shorten its life so I never gave it a try,go figure....Perfect reloading seems to be an endless quest,is it why we indulge in it????

 

[farmboy]

Boyd
I use that two stage process with my other calibers. I can't articulate why I haven't done so here.

I took Boyd's approach with this one piece setup, modifying it to 45* turns and the result is virtually 0 runout. For as much as I am gearing up to shoot, this needs to be a short lived process.

I sized some more cases with and without the expander ball and saw no effect on headspace.

What really surprised me out of all this was how straight cases were with an ordinary off the shelf sizer with expander ball.

A mediocre .012 feeler gauge under some cases gave me the shoulder bump I was looking for-.001-.002.

Haven't made up my mind whether I will get a 280 Rem collet die set(single dies appear not to be sold for this) and body die or have a 'custom' one piece sizer made. Due to seating depth required for the bullet, bushing dies are out this time. Yes I can machine .015? off the case holder for a short term fix.