O-ring under the lock ring ??

[Uncle Ed]

It still doesn't float like an O-ring equipped die in a conventional press.

I've loaded north of 10,000 rounds on my Co-Ax...far from comprehensive experience, but it is more than none.

That is why I use Lee lock rings, they are much cheaper than buying a Co-Ax press and work much better.

And there is a very good section in the Speer #9 manual dated 1973 and how to set up your dies to improve concentricity and reduce neck runout. And I'm still using my Rockchucker press I bought in 1973 and cheap bastards have more fun.

 

[chkunz]

Many years ago there were claims that the O ring reduced runout. I measured a statistically significant number of cases with various dies and press combinations. I got a mix of improvement, no improvement and makes matters worse. It is an easy test to do and you have to test your die and press combination to know for sure.

 

[cw308]

I guess if we're talking run-out , if your barrel isn't blue printed , wouldn't the bolt face to barrel add to the problem , as a extreme your case would be like a banana .

 

[bobinpa]

The o-ring started as a way to bump a couple more thou without loosening the lock ring on the die.... then along came somebody that figured it was for floating the die when the ram and slack in the shellholder is what did the floating. It has to help runout right? No- if it does its just a coincidence. You can put a die in a vise and hammer a case in or use a hydraulic wheel bearing press- the die does what its going to do as long as your press doesnt crazily push it in at an angle. Even the cheapest wore out lee press does the same thing as a rock chucker with the same die

Thanks for your explanation. I see the benefit of being able to make minor adjustments without having to deal with the lock ring and having the O-ring would help to keep the die from moving.

 

[bobinpa]

I have some pretty decent sizing equipment, and I can see some slight improvement in case straightness, measured at the case mouth, using a Sinclair concentricity gauge, comparing a regular lock ring with a Lee that has an O ring built in. That is all that I really need to know. If I had a lathe, I could make a jig to tell me if the sizing cavity of dies was coaxial with the threads, but I do not. So I do the simple comparison test and proceed accordingly. Another thing to ponder is whether the faces of lock rings are perpendicular to the CL of the threads. A friend and I did check this out on his lathe and I have a number of lock rings that have been trued. The most important issue here is whether any of this makes any difference at the target, and I have not been able to see that it has, probably because the differences are very small. I can tell you one thing, based on the earliest tests that I did, when I first got a concentricity gauge. Not all dies respond the same. I found that some did better locked up solidly, and some did better floating. The only way to tell was to test the die both ways. Do you have a gauge?

Thanks for your input, Boyd. My sizing equipment isn't extravagant at all. I use a Rock chucker press and either Redding or Whidden dies. I haven't been using the O-ring long enough to do a test both ways. I started to use the O-ring because of things I read on this forum that made sense to me. The logic behind using the O-ring is very basic and I couldn't see a downside to it, so I started using one. What I have noticed is that my cases don't get any worse. Right now I am playing with a 22-47 Lapua. So I had to neck the brass down, which I assume induced some run out, although I regrettably didn't check it. I did turn the necks just enough to give them an 80% clean up, so when I check the concentricity, I have a variation that I am seeing as run out. I am using an Accuracy One concentricity gauge. When I check my fired cases (which have only been fired once), I am generally seeing .0005 - .0015 run out at the middle of the neck, with a little of that being the variation in neck thickness. When I resize them, they don't get any worse. In the past, with other cartridges, my sizing methods were inducing run out, so at this point I think I am winning. When you take into consideration, neck thickness variation, case hardness and the chamber concentricity is it even realistic to expect .001 run out or less on a fired case?

 

[bobinpa]

If this does not get me kicked off the forum, nothing will!

I took no offense, so I would hope you allowed to stick around,

 

[snakepit]

A couple of other items that use O-rings for what they call "floating" are the Sinclair Expander Die Body and the Hornady Lock & Load Die Bushing.

 

[BoydAllen]

While we are on the topic, here is a little trick that I figured out that makes Lee lock rings work even better. Because the Lee rings do not have a split or set screw they are easily to accidentally move on the die when removing the die from the press. I solved this problem by adding a Hornady, split ring. I thiead the Hornady first, high enough to be out of the way, and then install the Lee below it, and adjust it and the die so that I have all the range of adjustment that I need by compressing the O ring. Then I carefully hold the Lee ring in position on the die, lower the Hornady ring down till it makes good contact, and then tighten it. The V thread swells the thickness of the Hornady so that it jams the Lee solidly in position. After that, all that I have to do is install the die on that press, to the point where the O ring makes contact, and then start making very small adjustments until I hit the bump setting that I want. If you are setting up a bushing FL die, and forget to pull the bushing before you thread the die into the press, take the top off of the die, and shove a neck brush down through the bushing and pull up to remove it. After you have the die set, reinstall the bushing and size the case one more time to do the neck. This saves over working the neck and gives you uniform work hardening within that set of cases/ necks.

 

[dolek]

While we are on the topic, here is a little trick that I figured out that makes Lee lock rings work even better. Because the Lee rings do not have a split or set screw they are easily to accidentally move on the die when removing the die from the press. I solved this problem by adding a Hornady, split ring. I thiead the Hornady first, high enough to be out of the way, and then install the Lee below it, and adjust it and the die so that I have all the range of adjustment that I need by compressing the O ring. Then I carefully hold the Lee ring in position on the die, lower the Hornady ring down till it makes good contact, and then tighten it. The V thread swells the thickness of the Hornady so that it jams the Lee solidly in position. After that, all that I have to do is install the die on that press, to the point where the O ring makes contact, and then start making very small adjustments until I hit the bump setting that I want. If you are setting up a bushing FL die, and forget to pull the bushing before you thread the die into the press, take the top off of the die, and shove a neck brush down through the bushing and pull up to remove it. After you have the die set, reinstall the bushing and size the case one more time to do the neck. This saves over working the neck and gives you uniform work hardening within that set of cases/ necks.

Boyd, I use the same method...works great . The o-ring is a great idea on it's own,but when paired with the Hornady lock ring I believe it is even better...makes for quick die setup also.

 

[Murray Brook]

I drill and tap all my Lee rings to use an 8/32 set screw.. Works great and keeps the die in adjustment and never moves.

 

[DUSTY NOGGIN]

so self centering & floating are just marketing terms to sell stuff?? i can understand someone trying this o-ring idea and having unexplained changes in there reloads , which could be perceived as helpful. thats cool , but is there anyone that can explain exactly what is fixed , and what runout could be bettered by using an o-ring

i'm kinda seeing, the only people that use this idea with a purpose are not really using it for the self centering or floating ideas . they are using it for ease of height adjustments only. so, is it just a workaround until someone can save up for some competition shell holders ??

 

[DUSTY NOGGIN]

there is another thread on these forums regarding this topic
http://forum.accurateshooter.com/threads/rubber-o-ring-under-locking-ring-or-not.3769002/

im seeing where some reloaders put the o-ring under the locking ring of the expander button stem , rather than under the lock ring of the die .. putting it under the stem lock ring makes a little sense so your not locking a bent or out of aligned expander crooked , but still probably be better to send a die back for not having threads be on the same axis , or straightening the bent stem

 

[dolek]

so self centering & floating are just marketing terms to sell stuff?? i can understand someone trying this o-ring idea and having unexplained changes in there reloads , which could be perceived as helpful. thats cool , but is there anyone that can explain exactly what is fixed , and what runout could be bettered by using an o-ring

i'm kinda seeing, the only people that use this idea with a purpose are not really using it for the self centering or floating ideas . they are using it for ease of height adjustments only. so, is it just a workaround until someone can save up for some competition shell holders ??

I have Plenty of money for competition shell holders...rubber O-ring works exactly like I want it perform.

 

[danny]

The die doesn't float in a Co-Ax press. It's just in a slot. When you cam the press shut, the die's TOP ring surface bears as solidly against the cast steel of the press body as any conventional press/die.

...and I dare you to try to get a normal O-ring to fit in there.

It does float, for certain. It just does not tilt, as you say, the ring bears against the slot, once it floats into position on the case centerline. It can float side to side and front to back.

Danny

 

[Intheshop]

Take a black sharpie and put a racing stripe on the die at your desired setting,front and center. Now,use whatever style lock ring you want...... just don't run it slam tight to the top of the press. Let the die have it's "wiggle room"....

I don't care for the O ring style at all..... on anything that really matters. They're fine on handgun loads. I like the split collars the best.... seems to tighten and not stress the die alignment as much as the set screw that goes straight in.

 

[Fliers]

For concentricity, I would think for a light seating die, it could help, but for sizing, wouldn't the force required just push the die threads against the press threads? I can see the o-ring allowing micro-adjustments for depth, but for actual press cycle, it would seem to much force to keep it not in full thread-thread contact.

 

[DUSTY NOGGIN]

I have Plenty of money for competition shell holders...rubber O-ring works exactly like I want it perform.

im assuming you are talking about putting in under the body of the die lock ring and not the seater stem and mainly using for ease of height control ?? cool, reload however keeps the smile on your face.

do you care to elaborate what performance are you getting and what the o-ring is doing to help or cure , that maybe couldn't be helped by gradual height shell holders ??

 

[mousegunner]

I tried the O ring with my LNL bushings but my sizing was inconsistent. I removed it and had better results. Don't know about run out but all things considered ammo was sub MOA and good enough for across the course shooting.

 

[Tuxedo007]

I use the O rings in every die set I own. As it has been stated, different dies respond differently, but the O rings make small adjustments easier to make. I like 'em!!

 

[BoydAllen]

If you evaluate each die, you will know what works best for it. In these discussions it is inevitable that the subject of what one would think, what "makes sense" comes up. If I have the means to test, then I test. Why not?