Tag Archives: reloading press

RELOADERS CORNER: Press Tricks, Linkage

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Reloading press designs vary, and some offer advantages, if they’re needed. Read more about which, what, and why HERE

rcbs summit
RCBS Summit

Glen Zediker

This is the last (for now) look at reloading press designs and features, and it’s all about power — leverage and linkage.

The more leverage a press can generate the less input effort from us is required in performing an operation, especially a more challenging operation like reforming cartridge cases, but that’s got another side to it. A longer stroke, and a heavier mass to move, also means more exertion on each stroke, and more time spent case to case.

Since we don’t always know the ultimately most demanding operation we’ll call on a press to perform, my advice is to err on the “stronger” side, and also on the “longer” side. I prefer a press with a shorter handle stroke (and a shorter ram stroke) because it’s less tedious to operate — but that’s true only when the press ops are not taxing. Yes, I’ll explain more: when the duties are sizing small to medium sized commercial brass cases (like .223 Rem. up to .308 Win.), seating bullets, decapping, seating primers then excess press isn’t needed. But when it’s more taxing, like in the case reforming already mentioned, and also sizing once-fired military cases, or loading for a honker like .338 Lapua, a longer ram stroke and more leverage is most welcome.

reloading press design
Forster offers a shorter handle option for its CoAx because there are many who want to increase feel on some ops. The shorter handle reduces leverage.

I’ve been doing all this long enough to have collected more than one press, at more than one “size,” and I’ve used them all over a good many years. The one I use the most is on the smaller, shorter end of the press spectrum, and that is only because the most of the loading I do now is decidedly not taxing. But give me a Kroger sack full of Lake City 7.62 and my Forster CoAx or Harrell’s Sportsman is getting mounted up on the bench.

Speaking of effort, case lube is decidedly important in smoothing out taxing sizing ops. I prefer a petroleum-based lube, but that’s not meant to start an argument!

There are a few different takes on the best way to design linkage (the levering mechanism that powers the ram), including those that operate more or less upside down. I’ve not used them all but have, generally, found that handle length has the biggest influence on leverage.

reloading press design
A press that’s set up to “cam-over” really means it’s set up to flex. Any press with enough leverage can warp over on itself. This is a Harrells Sportsman: huge leverage.

Cam Over
Speaking of linkage… Some reloading presses are designed with eccentric linkage such that it’s possible to “cam” the ram. The concept involves circular motion and linear motion, meaning that when the ram traveling in a linear path reaches full extension, the linkage which is traveling in a circular path, can move through the 0-degree mark and go to a negative degree — like a crankshaft in an engine. To get a picture of this: As the handle is moved downward to elevate the ram, the ram reaches its maximum height just short of the very limit of its travel upward, and, at the last little bit, lowers. So when the handle is all the way through its arc, the press ram is sitting a little lower. This action, called “cam over,” has essentially increased “ummph” in the linkage, and it’s done that by making contact (plus) with the die.

I’m not a fan.

Now, any substantial press, whether it has eccentric linkage or not, can produce the effect of camming-over. A Forster Co-Ax, for instance, can just about crush a chrome car bumper and doesn’t have eccentric linkage. To set up that press, any press, to cam-over, turn the die a little (1/8 turn or so) downward beyond what provides full and flush contact with the shellholder when the ram is at its full height. Then, when the press handle is fully down, the additional pressure in the last bit of the handle stroke goes toward flexing the press. Simple as that, and that is what camming-over does: flex the press. And, again, that’s true whether it has eccentric linkage or not.

Don’t do it. Just don’t.

There’s no need to cam-over a press for a case-sizing operation. It creates unnecessary stress. Dies can get deformed and bent, carbide dies can break, and the press hisself can suffer, and even break. Some defend this practice by saying presses are designed to “take it,” but eventually there’s a penalty for taking any machine to its limits, continually.

The real deal is that it’s just not necessary! Using a cartridge case headspace gage to determine sizing die positioning to get the correct amount of case shoulder setback, it’s clear that sure should occur at a point short of full contact between the die bottom and the shellholder surfaces. But, and this is important, if it’s not then trying to push a case farther up into the die by crushing the shellholder against the die isn’t going to do much. Done is done. The flexing might, maybe (maybe), increase setback 0.001.

If your sizing die doesn’t adequately set back a case shoulder, then that die has to be modified by having material ground off its bottom.

Camming-over a press is a “feel-good” measure for some folks: there’s this satisfying “ka-thunk” at the limit of press handle stroke, and that lets a loader know that they gave it all it could get. I’ve also had some claim that the stress and flex brings “everything into perfect alignment.” No it doesn’t. Alignment in a press was determined by the maker, not pressure. If your press hain’t straight, bending it more won’t help.

Cam-over has its application in some bullet making operations, but those are not on-topic here.

reloading press design
Here’s eccentric linkage at work. On left is the maximum height attained by the ram; on right is the ram position at the full-limit stop on the press handle. It’s 0.020 inches on this press, a Harrells Turret.

More, And Some Is Good!
To find out if you have a “cammer” run the press ram fully up (press handle fully down) and thread a die in until it touches the shellholder. Try to move the handle back down. If it won’t budge, it’s got eccentric linkage. It won’t move because the ram is trying raise again. Back out the die until the handle moves and pulls the ram away. It’s at this point where “flush” contact with a die bottom will be. As long as the shellholder is not being contacted, presses with this sort of linkage have a smooth feel to them and do a little more positive job of sizing. In effect, the case gets sized twice (the ram elevates again just as the press handle is lowered). Linkage, either way, has zero effect on setting up a die because you measure what you get anyhow, and adjust the die accordingly, after you see what it is that you got.

The preceding is a adapted from information contained in from Glen’s books Top-Grade Ammo and Handloading For Competition. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.

 

RELOADERS CORNER: Press Tricks

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There are a few tricks and treats, and traps, in reloading press designs and associated pieces-parts. Shellholder first. KEEP READING

shellholder tricks
I honestly have had my best luck with Lee brand. Lee is inexpensive but I’ve yet to have a bad one, or one that wouldn’t work on different press brands (and I’m not alone in this opinion; a famous Benchrest competitor gave me the “Lee tip”). SEE IT HERE

Glen Zediker

Last couple of editions started a “press primer,” and this one should finish it off, at least for now.

Shell Holder Options
A correctly dimensioned and well machined shell holder is absolutely necessary.

Small differences in individual shellholders, and certainly in different brands of shellholders, mean that a shellholder change makes it necessary to check case sizing and bullet seating results again. Adjustment will likely be required. If a shellholder is a little bit thicker or thinner such as will influence the cartridge case “height,” then that’s transferred to the end result as measured in, for instances, cartridge case headspace and bullet seating depth.

That is exploited by some who produce shellholders with varying heights. These come in a set and have incremental differences that allow you to move a case up or down by swapping the shellholder. If you load for different rifles using the same die, and if these rifles all have a different ideal cartridge case headspace, for instance, then there can be less compromise without having to use a different sizing die.

shellholder tricks
Redding offers shellholders with varying heights to allow for small effective changes in sizing. Handy, for instance, for someone who loads for more than one rifle and wants to use the same die. There are 5 holders, each with 0.002-in. height difference. SEE IT HERE

Not all shell holders are interchangeable! They’re supposed to be, generally, but I’ve purchased different brands for use in differently branded presses, and they won’t fit.

Shellholder Tricks
Speaking of fit, check over a new shellholder for burrs and make sure it fits fully and freely into its slot in the press ram. And, speaking of its slot in the press ram, I have long been a believer in getting rid of the “spring clip” virually all presses use to secure the shellholder in place. The spring clip sits the shellholder askew atop the ram.

This clip can be removed. I use an o-ring as can be found at a real hardware store to fit into the outside slot formerly occupied by the clip. The elastic o-ring keeps the shellholder from coming slap out, but also takes a little (to a lot) of getting used to because the shellholder is free to spin and shift. It no longer snaps satisfyingly and firmly into place.

shellholder tricks
I’ve shown this before but it (really) works well to improve alignment odds. Canning the shellholder retaining clip so the part can sit flush and move a little helps it all self-center. This is a 7/8 o.d. x 11/16 i.d. x 3/32 thick o-ring that suits most press rams.

This arrangement lets the shellholder fit flat-flush against the ram and, very important, allows some “wiggle room” to let the shellholder float so the cartridge case can seek its own center as it enters the die.

I am absolutely convinced that a floating shellholder is a big help toward attaining concentricity in a round.

All mating parts surfaces have to have a tolerance. Lower (closer gaps) is better, but it can’t get too low or the dang parts won’t fit together. The way I see it, the more room for movement the bigger trick it is to get everything in alignment, if we want to lock it all in-line. Shellholders are fairly loose all around: the shellholder has to fit into the press ram slot and then the case has to fit into the shellholder and these fits are fairly free. Attempts to lock a shellholder in place, frankly, are contrary to best alignment, with maybe one exception.

On the other end of this, and this qualifies as a press “trick,” Forster has its own take on shellholder design. The Co-Ax shellholder uses what amounts to clamping jaws that are engineered to take up the slack in each individual case and lock it in dead alignment with the press ram. I’ve used Forster long enough and made enough gage checks, and shot enough high-x cleans with the resulting rounds produced on this machine, to tell you that it it, indeed, works. Years ago I tried an aftermarket add-on version of this concept produced by Quietics, makers of the original “inertia” bullet puller. It’s still available. Like the Forster, the same setting will work with a variety of cartridge sizes and that was the main draw to this “universal” shellholder.

shellholder tricks

shellholder tricks
Forster uses a proprietary system that gets a case centered with the ram and keeps it securely centered during a die op. Their Co-Ax design is pretty much a clamping shellholder. SEE IT HERE

Keep the shellholder and its slot clean. As often said, running a separate decapping station keeps the majority of gritty gunk off the main press parts.

The preceding is a adapted from information contained in from Glen’s books Top-Grade Ammo and Handloading For Competition. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.

 

RELOADERS CORNER: Press Principals

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This mechanism is at the heart of a rifle reloading setup, and options abound. Here’s what really matters, and how to know what you need (and what you don’t). READ MORE

coax press

Glen Zediker

A press is usually the first thing mentioned to a new handloader when the question is “What do I need to get?” Can’t, pretty much, load without one. The press houses the sizing and seating dies, and other tooling, and can also serve as a primer seater.

Shopping for presses shows a big range of prices, and sizes (usually related), and also some type or style options. The press type I’m going to be discussing here in this bit is called a “single-stage,” and it gets that name because there’s one receptacle for any thread-in appliance, such as a sizing die. It can then perform one single operation.

The standard receptacle has 7/8-14 threads.

reloaders corner presses
This represents a “big” press. Forster Co-Ax. It’s a honking piece of metal with unique and worthwhile features. Powerful leverage. I’ve got a couple of these (one for decades) and the reason I chose to use it to illustrate this article is because it’s that good. Not cheap. Not chintzy. If you get one you will never (ever)need another press, or likely want another press. See it HERE.

The main option is the size of the press, which means the press body size, ram extension distance, and handle stroke arc and length.

When is a “big” press best? When operations require big leverage. Or for really big cartridges. Or when using a press to perform an operation that’s more power hungry than case resizing or bullet seating. Given a choice of “small,” “medium,” or “large,” as many times, I’d suggest going at least “medium.” Unless, that is, you have compelling reasons to get another. Don’t underpower yourself. On the other hand, you decidedly do not (usually) need a tower of power, and might even find it’s kind of in the way.

reloaders corner presses
Here’s my “personal” press: Harrell’s Precision Compact. These are precision machined, well designed. This one, though, maxes out at a .308 Win. case length. It’s not for case forming, but routine small-case sizing ops and seating are efficient and easy. See it HERE

I like the operational efficiency of a smaller press, one that doesn’t have a big stroke arc. In sitting and doing a large number of press ops I really notice the additional effort of cycling a bigger press. However! There’s also sometimes no substitute for torque. Sizing unwieldy military cases, for instance, on a honking press takes a less effort from the self.

As I’ve mentioned in these pages before, I also like being able to move my tooling around on my workbench bench, or even into another environment. Smaller presses are easier to tote and easier to mount.

reloading presses
Here’s my recommendation for most everyone loading most any routine rifle cartridge: Hornady Lock-N-Load Classic Single Stage Press. Alloy body, plenty of window and leverage, and a most fair price. See it HERE. If you want a similar cast iron press, you cannot do better than a Redding Boss. About the same cost. See it HERE.

redding boss

It really depends on what you are loading for. A smaller, shorter case, like a .223 Rem. or 6.5 Creedmoor, or a bigger round like .30-06 or .338 Lapua? As with many things, most things maybe, going bigger to start is a better investment. By “bigger” I mean a press with a window opening big enough (or that’s what I call the open area available between the shellholder and press top) and stroke long enough to handle the longest cartridge you might tool it up for.

Does weight matter? Not really. A heavier press doesn’t necessarily mean it’s more rigid or effective (or not for that reason). Modern alloys are every bit as good as cast iron, and there was a time when I was uncertain of that. Speaking more of materials, cast iron has been, and honestly still is, the “quality” material used in press construction. Cast iron is rigid. This material is, well, cast into the essential shape of a press, and then final finished (faced, drilled, tapped, and so on). The only part of a cast iron press that’s cast iron is the body of the press. Aluminum, other alloys, or steel are used to make the linkage and handle, and other pieces parts. Cast iron can’t really bend which means it can’t warp. Cast iron just breaks when it hits its limit of integrity. It can flex (just a little) but returns perfectly. Alloys or metal combinations used in the manufacture of presses nowadays are pretty much the same in performance and behavior under pressure as cast iron. The essential compositions vary from maker to maker. I have cast alloy body presses and others that are machined from aluminum stock. These are all lighter but just as rigid as cast iron. Press architecture has a whopping lot to do with how rigid it is (and its leverage has a lot to do with linkage engineering).

What matters much is the sturdiness of the bench and how well the press is mounted to it. What might feel like press flex is liable to be in the bench, not the press, or in the press handle itself.

Alignment — straightness — matters in a press. This is the concentric relationship between the threaded tool receptacle and the press ram. They, ideally, will be dead on, zero. Then of course the die has to be “straight,” with its threads correctly cut and insides reamed on center. And then the shellholder arrangement has to likewise be dead centered with everything else. There is a lot of play in a 14 pitch thread. All this means is that a “straight” press doesn’t automatically mean you’ll not see issues with tooling concentricity. More in another article shortly, but at the least the press (body and ram) should not contribute to create concentricity miscues. I know of no manufacturer that doesn’t claim correct alignment in its product, but I also don’t know if it’s something they’ll warrant.

reloaders corner presses
I use a tiny Lee-brand press to run a Lee-brand decapping die. Keeps grunge away from the “expensive” press. Wise. This whole setup costs about $50.

Presses do require, or at least should get, maintenance. Keep it clean! There’s a lot of abrasive potential from incendiary residues, and that will, not may, wear the mechanisms. I have often and for many years recommended a separate decapping or depriming station.

CHECK OUT DECAPPING TOOLS HERE

The preceding is a adapted from information contained in from Glen’s books Top-Grade Ammo and Handloading For Competition. Available HERE at Midsouth Shooters Supply. Visit ZedikerPublishing.com for more information on the book itself, and also free article downloads.