Do single stages really produce more accuracy than progressives?

[Machineguntony]

Has anyone done a comparison test using same loads and same components on a single stage versus progressive?

I just got into long range and accuracy shooting. I really don't want to start using a single stage.

I've read a few articles on the subject of single stage versus progressives for accuracy. A lot of people assume that single stages are more accurate, but there are some shooters who claim they do just as well on a progressive.

I'm curious if anyone has any actual shooting results that they can share.

I just ordered a ton of match grade 308 MatchKing 180 grain bullets. They're on sale right now at Wideners, btw. Hurry!

[Jimro]

In theory, you can get more accuracy from a single stage due to less tolerance stacking.

In practice, whether that makes any difference at all has a lot more to do with your rifle and shooting distance than anything else. The benchrest crowd is mostly single stage and arbor presses. The High Power and Palma crowd is mostly progressive and turret presses. But you'll find overlap of course.

So if it isn't benchrest you are shooting, no need to load single stage for accuracy reasons.

Jimro

[Mozella]

Like many reloading procedures, actually quantifying a small potential difference is difficult if not impossible. For example, I uniform my primer pockets only once when I first prep factory brass, even Lapua. But some of my competitors uniform their primer pockets every time. On the other hand, I anneal every time and they don't. Differences? I think it comes down to that you "think" will help. I've done enough testing to be convinced that you'll wear out your barrel before you can truly find a measurable difference in a single procedure which is expected to produce only a tiny improvement, if it does so at all.

Chances are small improvements all add up, which is why most of us do a lot of prep work and take great care trying to make the best reloads. But deciding exactly how much a single procedure helps is hard to say.

I do know this. I hate handling individual pieces more than necessary and that's why I use a Lock N Load progressive with a DIY case feeder for both plinking ammo and competition ammo. I shoot single shot rifles and keep my brass clean at the range, so my competition routine is lube then set up my press to batch feed, deprime, bushing neck size, body size, and finally insert a special sizing mandrel to uniform the neck, all in one pass through the press. Then I trim, chamfer, wet SS clean, dry, and anneal. Next I batch feed the brass through the press where I insert the sizing mandrel again as I prime. Next I weigh each charge to .02gr, fill the cartridges and finally use the press as a single stage to seat the bullets. This makes ammo good enough to win my fair share of local 600 yd F-class and BR matches.

That involves plenty of individual handling, but not nearly as much as a single stage press. For plinking, the progressive really shines because once the brass is clean, I can prime, charge cases, and seat bullets in one pass by only handling the bullets. And if the world collapses and you need a lot of rough ammo in a hurry, you can eliminate cleaning and do the whole process in one pass.

Of course I carefully measure my finished competition ammo and find that it is well within accepted tolerances for seating depth, run-out, etc. Plus it seems to work well. The progressive press takes out just enough of the PITA factor so that I don't mind loading ammo.

For example, this week I did some fine tuning of seating depth and loaded a batch of competition ammo based on that testing; i.e. I made two medium sized batches in a few days without dreading the job. My shooting buddy who uses a single stage press has been looking at a pile of cases for over a month and just can bring himself to trudge through the tedious reloading process. Tomorrow I'm going out of town for a match but he's staying home since he couldn't bring himself to get ready using his single stage.

Of course, your mileage may vary. But if you ask me, a progressive press is plenty accurate and makes my life easier. I'm going to stick with my progressive until I get so crazy that I start weight sorting my primers.

[Metal god]

In practice, whether that makes any difference at all has a lot more to do with your rifle and shooting distance

and ability

If you cant shoot well enough to notice 1/4 moa differences or less then not sure you'll notice how you loaded the round .

I do all rifle loading on a single stage and all pistol on a turret . I don't nor ever have used a progressive press . I do know one thing for sure , I use stick powders for all my most accurate loads . It does not throw/meter worth a crap and if you're shooting at 500+ yards you're going to want a consistent charge .

Then there's the idea of the feel a single stage gives when loading a progressive just can't do . I like to feel the bullet being seated . This lets me know if my bullet hold is consistent . That's something you could never feel if your press is sizing a case at the same time it's seating a bullet .

I think the whole thing comes down to feel and micro control of each step/stage in the reloading process .

If you want to know how to load the most accurate ammo . Speak with a winning BR guy . That does not mean that's how we all should do it . It just seem to me BR guys are less shooting there rifles then they are loading the most consistent rounds possible . They all have crazy accurate rifles . It's who can load the best ammo at that point .

I don't need to load my service rifle like a BR shooter because I cant shoot MOA with the rifle . Hell I can't shoot 3 moa with the rifle on the 200yd stage . So really how am I going to notice 1/4 moa difference in my load .

[JeepHammer]

Not in 'THEROY'...
Actual hands on experence says yes, you can produce a higher tolerance, more consistant round with a SOLID single stage, 'O' frame press.

It's not going to happen overnight,
And you MUST learn to produce brass that fits YOUR rifle chamber.
Most people ignore that part of things and try to produce 'General' or SAAMI rounds...

Produce brass that fit YOUR chamber, and it will help...
Mostly help you limit the number of variables that creep into volume loading.

[Jimro]

JeepHammer,

And removing press induced tolerance stack entirely is why some BR shooters use arbor presses.

But until you've got highly consistent, brass, bullets, powder, and primers, and the dies to match, I don't think it matters much what press you load on. Which is why with budget dies, bulk bullets, and unsorted brass, there really isn't any measurable benefit to loading on a single stage.

Jimro

[Slamfire]

In a hand held rifle, I can't tell a difference. I have been squadded with President's 100 winner's whose reloading practices were described as barbaric.

The shooter is the greatest source of error in the system. Incidentally, Federal Gold Medal match, a benchmark for accurate ammunition, it is not loaded on a single stage press.

[JeepHammer]

I agree.
'Blasting' ammo is for making noise, not much else.

My 'Range' ammo is very close to my 'Match' ammo.
When I'm doing Match ammo I size/weigh bullets and use once fired cases,
'Range' ammo uses up the frequantly fired cases, +/- size/weight bullets.
Excessively high/low weight bullets get used for blasting ammo...

My bench ammo is just that, hand built on the bench, as close tolerance as I can produce. Fits a *Specific* rifle and I don't even try it in others.

[Sure Shot Mc Gee]

Single stage better: I'd say yes for rifle cartridges. Pistol: I don't think so concerning a original condition stock hand gun. After a accurizing job done to a hand gun. Without a doubt Single Stage Press cartridges are more reliable & accurate than most progressive press's.

[firewrench044]

When I started shooting High Power Rifle Competition
as a beginner I ask a lot of questions and listened to a lot of advice

Part of what I learned was it is necessary to load on a single stage press
It gives you better ammo and therefore an edge over your competition
that does not

Over the years I have seen the difference in the scores of the people
that do and the ones the do not use a single stage press

And they gave me good advice !

It comes down to speed or quality

[springer99]

Having used single stage presses, auto-indexing turret presses and now a progressive, I'd have to say that how carefully you prepare your cases for loading, how critical you are to only use "match-grade" bullets and primers, and how consistent you are in throwing charges from a measure, are much more important to accuracy than simply the type of press used.

If you aren't using only one mfg. of cases and always trimming cases to the same length, including possibly neck reaming the cases to boot; priming them with a hand priming tool to the same depth, you'll never see a difference.

[rox]

The last batch I prepped & loaded on my progressives was a run of 1,000 resulting in trim length and shoulder datum being held within +/- 0.001", and the SD of both dimensions was 0.0005". CBTO measurement of seating gave an SD of 0.0006". I don't think any of these measurements are any worse than I achieved on single stage presses, and it's pretty much at the limits of my measuring tools, but maybe others get better results than this on a single-stage.

I don't use on-press powder-throwers, but instead drop weighed charges from a very fast dispenser, so this slows the speed of the loading pass to between 150 and 300 rounds per hour (depending on the required charge tolerance), but case-prep can reach 1,000 cases per hour.

As for the comment about not feeling bullet seating because sizing is happening: sizing is usually done during the first pass through the press, so it can't obscure the feel of seating which happens during the second pass.

I load for Palma shooting to international level, and 300m shooting, on progressives (a pair of 1050s). It works for me, but I often read that there is too much slop and movement in progressives.

[Jimro]

firewrench044,

My experience in High Power (Service Rifle) is the opposite. Spend more time practicing and less time reloading was excellent advice for me. The 10 ring is over 2 MOA, so getting me to be a 2 MOA or better shooter is more important than ammo that is 0.8 MOA versus 1.1 MOA from the bench (a shooting position strangely not found in High Power..)

Scores went up when I got a progressive, as a lot of that time I'd been reloading turned into dry fire and air rifle time.

Jimro

[Metal god]

I took the OP's question to mean using a progressive in the traditional sense . I did not read it to mean on some parts you use your progressive like a single stage and others in some other way . I figured he meant 3 or 4 pulls and your rounds pops out done .

shoulder datum being held within +/- 0.001", and the SD of both dimensions was 0.0005".

That right there is VERY impressive for any progressive . I can get that with my single stage but only when using competition shell holders and hard contact with cam over . My chambers tend to be a tad long so a +4 or +6 shell holder is needed . I'm assuming your chamber is on the short side of spec and the die and shell plate are making good contact when you size those cases that have those tolerance numbers ??

[BigJimP]

Today's higher end Progressive machines...( Dillon 650, Hornaday LNL, etc ) are solid machines - capable of very consistent and high quality completed cartridges....so no, I don't think there is an advantage to a single stage press.

Accuracy in my view ...in handguns ...has more to do with the quality of the weapon (the barrel, frame, slide -- barrel lockup, trigger mechanism, etc...) ...although the quality of the gun cannot overcome inconsistent ammo.

I don't do much long range rifle shooting anymore...but in my view consistency is the issue on rifle ammo as well...and I think a good progressive press will give you what you need.

[rox]

I'm assuming ...the die and shell plate are making good contact when you size those cases

I don't use hard (or any) contact on the sizing die, but I do have a dummy die body directly across the toolhead from the sizing die, that contacts the shellplate to balance the forces and prevent variable sizing force from 'tipping' the toolhead to a varying degree.

I'm assuming your chamber is on the short side of spec

I generally adjust the sizing dies to give about 0.002" under chamber size. Most of my chambers do happen to be smack-on SAAMI min, but since the sizing dies aren't contacting the shellplate I guess that doesn't matter. Progressive shellplate decks aren't necessarily the same height as shell-holders, and I've had to trim the mouth of a few sizing dies.

I did not read it to mean on some parts you use your progressive like a single stage

Which aspect of the process do you think is using the press like a single-stage: the 2-pass process, or dropping weighed charges? In either case, multiple operations are happening with each pull, and at a much faster rate than working with a single-stage. Two-pass processing is quite commonplace for progressive bottle-neck FL-sized rifle loading. Otherwise you have to load lubed brass (possible powder contamination and clumping) and then delube loaded rounds; not things I'd like to do, though some folks do. I used to run a single-pass process (lubeless neck-sizing and shoulder bump), but when it's so quick and easy to produce FL-sized and trimmed brass I haven't bothered for a long time.

..

[mikld]

Not a benchrest shooter here, and most of my rifles can shoot waaaay better than I am able to. But, if it were me, and I wanted a progressive anyway, I'd go ahead and get a progressive press and do a trial. Load you "perfect load" on both machines and see what turns out best and use that method for "competition" ammo. Plus there's always room on a bench for both kinds of presses. I'd have to shoot at least 100+ comparison rounds to overcome what I "think should happen" and just rely on what the gun/ammo does. If I "think" a load is inaccurate, or "just plinking ammo", I more than likely won't be able to shoot worth a hoot...

[jmorris]

David Tubb uses a 550 and Prometheus powder measure. If more accurate ammunition can be loaded on a single stage it hasn't been able to top many of his records.

While one can produce a lot of inaccurate ammunition quickly on a progressive, one can also take hours on a single stage making the same amount of inaccurate ammunition.

The common misconception is that taking forever means more precision. Some also feel the more you leave up to a person the more chance you have for human error.

You might be surprised how many reloaders with single stage presses can't produce ammunition as accurate as premium factory ammunition, made by the thousands per hour.

[GJSchulze]

I shoot only pistol in USPSA and IDPA, so perfect accuracy isn't that important to me. I do, however, have a question about producing such accuracy. I'm skeptical of many reloading practices and claims of making super accurate ammo, but I do want to understand what really works and why.

1) what is the single most important factor affecting accuracy as the bullet reaches the end of the muzzle? Is it velocity, twist rate, precession, or something else. Not what causes it, but the attribute of the moving bullet.

2) what is the second most important factor?

By accuracy, I assume we mean small shot groups, yes?

[Metal god]

As for the comment about not feeling bullet seating because sizing is happening: sizing is usually done during the first pass through the press, so it can't obscure the feel of seating which happens during the second pass.

I interpreted that to mean you size all your cases before running them through the rest of the stages . I did not realize there were passes in a progressive . I thought by the 4th pull you were producing 1 round every pull there after . If not then your not using the progressive press in the traditional sense . If the case ever comes off the press to be inserted again later . Then your not using it as intended and how I thought the OP was asking the question . If your going to change the intended process then now we're just talking degrees of differences to get to where you want to go .

I don't use hard (or any) contact on the sizing die, but I do have a dummy die body directly across the toolhead from the sizing die, that contacts the shellplate to balance the forces and prevent variable sizing force from 'tipping' the toolhead to a varying degree.

I may not be understanding that either . Where is that on the tool head , where the seater or the crimp would be and is that semi permanent ?

[JeepHammer]

The only way I got my Dillon 650s to crank out suitable 'Match' grade brass was by using two sizing dies,
One that only punches the primer, no sizing ball, and has the neck hones out so it doesnt over compress the neck, and sizes to more or less what I'm looking for,
The second is high precision, sizes the neck to exactly what I'm looking for.

Then its off the trimming for length with a datum point trimmer...
*IF* the case is going to be off on length, I'd rather it be in the neck rather than the headspace...

My Dillon required some TLC, not all tool heads are created equal, and shimming them turned out to be a requirement,
You have to keep a CLOSE eye on the shell plate to ram bolt or it introduce slop,
And I put a rod down from the tool head that contacts the shell plate opposite of the sizing dies to stop shell plate deflection.

I've also installed a 'Button' under the first sizing die in the ram 'Cup',
Hole for primer to drop through,
Helps stop deflection by supporting the case/shell plate while on the 'Up' stroke.

Actually, I think the thing that helped most was the rod opposite sizing dies, down from tool head. Incredably easy to do and keeps that shell plate from toggling...
Wish I'd thought of that before I ruined the first ram 'Cup' trying to figure out the button!

[briandg]

Like many reloading procedures, actually quantifying a small potential difference is difficult if not impossible.

There's this old cliche about art and science, and it fits. Science and mechanical expertise are not the absolute final answer in this field. When you are dealing with variables that control ultimate accuracy, I suppose that the press is probably pretty far down the list of things that will cost significant accuracy. I suspect that unless you can reliably turn out 1/2 moa groups or even smaller, it won't matter. the difference between a $400 single stage and a $1,000 turret or progressive that is designed for match rifle loading is going to be kind of moot unless you have cleared all of the other hurdles first.

[buck460XVR]

I just ordered a ton of match grade 308 MatchKing 180 grain bullets

If that's the case, I'd stick with the progressive. 78,000 rounds on a single stage would take over a lifetime to roll.

Just sayin'.....

[briandg]

I've known guys who buy shot by the ton. Not may who did so for ammo.

[jmorris]

You have to keep a CLOSE eye on the shell plate to ram bolt or it introduce slop,

That is where the 550 is superior to all the other Dillon progressives, the shell plate is only there to pull the case from the dies. The bottom of the case does not ride in/on the shell plate.

A ton of brass isn't as much as you think, each one of these has more than a ton in them.