How critical is a quality seating die?

S

SEHunter

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I have a basic understanding of the internal configuration of a seating die but what's the difference between a competition grade seater vs a standard one that is included in a base level 2 or 3 die set? I have RCBS 2 die sets for all my bolt guns and have replaced the sizing dies in each with a Redding type S bushing die as of a couple years ago.

I just picked up a new bolt gun of a chambering that I didn't have before so I'm picking up all the chamber/caliber specific components to prepare for hand loading it in the near future. It's a .270 and I found an old (probably 30+ years) Lyman 2 die set that I forgot I had but my whole point in this thread is that I want to save a few bucks by only buying a sizing die and just using the old Lyman for a seater. I don't crimp and I use the Lee decapping die for spent primer removal. Is there any reason not to trust the old Lyman to seat my bullets?
 
Measure the bullet runout you are presently getting. If you are happy with the runout, then there is no reason to get a competition quality seater.
 
That's a "roger" with the above recommendation to check your runouts and also compare what you get with factory loads. Of course the runouts for the reloads will not all be the same, and likely not the factory loads for any box of rounds. You might get anywhere from .000 to .007, etc. But in the end I didn't find competition seating dies to be more beneficial accuracy wise than standard dies with sporter rifles. I experimented with quite a number of calibers and considered .003 or better runout to be good, with whatever seating die, but could not get that consistently, maybe only 30 to 40% of the times.
 
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I have a Sinclair concentricity gauge. I have a spreadsheet to track my 301 reloading dies.
If I measure the concentricity at each step, there is some tiny contribution during seating ~ 0.001".
The Sliding seater Forster patent type seater that costs extra is better butt...

I can load ammo with plain Jane RCBS die sets that will shoot better than I can.

So why spend extra money, when the contribution is so small?
A) Finatics
B) Old men with millions $
C) A fool and his money soon part
D) Great marketing
E) Status
F) All of the above
 
I have purchased several of the Forsters Ultra™ Micrometer Seater Die mainly because I play with several different bullet types/weights in my rifle loading (223 & 308) and it is much easier to adjust seating vs the good old stem and lock nut types. I have never tested runout - I just like the ease of adjustment... Yes, a fool and his money are soon parted! But, it works for me. That being said for my hunting rounds (243, 270, 7mm, 300 WM, etc) I do stick with the standard RCBS dies that I have had for 20 - 30 years, as I do not change bullets often...
 
Ok. I'll give it a shot with 4 or 5 rounds before I load a large batch then check run out. If it's .003 or less I'll use it. If not, I'll pick up a new seater. Thanks guys.
 
I have nothing more than the standard RCBS & lyman reloading dies, many are 30 or more years old, if I do my part they still produce ammunition that will group less than an inch. I checked and found dates on my RCBS dies from mid 70's and early 80's, I have nothing that is dated later than 1983.. I have standard setting dies only, I never felt the need to buy competition seating dies because If standard dies produced 1' or less groups that was good enough.... I still remember a Winchester model 70 .243Win that would shoot 3/8" cloverleaf groups every time I went to the range using standard RCBS dies.. Non the less I have loaded ammunition for more than 48 years, it has been an interesting and fulfilling hobby and I would do it again thanks to Jack O'Connor shooting editor of Outdoor Life magazine.. William
 
"...what's the difference between..." Mostly the price. RCBS 'Competition' seating dies, for example, do not crimp and are micrometer adjustable for seating. Also $139.45. Millions of rounds of match grade ammo has been loaded long before they came along.
All the manufacturers have to introduce new stuff regularly or risk losing market share.
 
I have seating dies. I have universal seating dies. Basically that is a die body with different seating plugs. I have competition seating dies with different names. And then I have seating dies that came in a box with a full length sizing dies.

For accuracy nothing comes close to an accurate rifle. My favorite seating die centers the case neck with the bullet. I have RCBS competition and Gold Medal seating dies, I do not have a cabinet full but I get all the use out of the dies I have. One die body allows me to seat bullets for three different cases after adding attachments.

I understand the seating die does not have case body support, for the most part case body support tis not necessary. When seating with standard seating dies a radius on the base of the bullet and a chamfer on the inside of the neck aid in seating.

I have a few Hornady dies with the sliding sleeve.

F. Guffey
 
I had an RCBS .257 Roberts die that would not seat a bullet with less than .017 runout. On the other hand, most of my RCBS dies would produce ammo with .005 or less. So, you must measure runout and then decide if you need a better seating die.
 
I had an RCBS .257 Roberts die that would not seat a bullet with less than .017 runout.
Click to expand...

dahermit, If the seating die does not offer case body support etc., etc.. I would think there was more going on than the make, brand and model. I have had seating dies that were powered by the palm of the hand that did better than that.

F. Guffey
 
From the Precision Shooting Manual "Reloading For Competition"...as well as I can remember from when I read it...
If the dies are in good shape they are probably capable of loading very concentric ammo...if you do your part.
First,use your case trimmer to make sure the necks are square.Hard to start a bullet in straight otherwise.
And chamfer your case mouth so the sharp edge won't dig into the bullet.
Then run a nylon bore brush on one of the RCBS or other handles in and out of the neck.

Next trick.Setting the lock ring.The above mentioned article recommended an o-ring under the lock ring.He believes it helps with concentricity.
The other thing is about the self centering nature of the 60 degree thread angle.Given a chance,those threads want to settle into center.It was recommended to snug down your lock ring while the die is under load from the ram.
I must be forgetting something about the procedure,because ordinarily you do not want the seater die to contact the shellholder.
The reason:Most seater dies have a crimp function built in.Bumping the die to the shellholder makes a very heavy crimp and often collapses the case shoulder.
I'll bet someone else knows the part I forgot.Having a hardened,ground shim washer of a desired thickness to set the die the same way each time would be good..A regular hardened machine washer ,if it is flat and parallel will work.Keep it in the die box.
Even with this procedure,a runout check is best.That author of the Precision Shooting manual ,IIRC,expected .003 max for "pretty good"ammo.He said via his method,standard RCBS dies could perform with the floating bushing seater dies for runout.
Disclosure,I'm repeating something I read once.
I get good results from standard dies...
Of course,the press plays a role,too.
 
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I think it is time for some reloading die explanation here.

A normal sizing die sizes the outside of the case and pulls the neck inline with the expander. Essentially, the outside of the body and inside of the neck are concentric.

The basic seater gets the body roughly aligned and pushes the bullet in.

This gives hunting level runout and accuracy.

A bushing die makes the outside of the case neck aligned with the outside of the body of the case. If you don't neck turn, you just added runout into your system. If you do, the process is more accurate and more concentric, because expander balls always have alignment issues making them flexible or misaligned slightly.

A sliding sleeve seater aligns the od of the case body nearly perfectly with the bullet axis. A concentrically sized case should have even lower runout.

In a nutshell, replacing the sizer with a bushing sizer will increase runout by a noticeable amount.

To do something on the cheap, I would recommend whole Forster die set with the micrometer top. Then add a bushing bump die and neck turning to get that last bit of concentricity.
 
What is the point unless you are using competition grade bullets?

I have vintage Hornady bullets for .32 Winchester and .25-35 and just looking at then I can see that the ogive varies from one box or lot to the next and that will make a larger difference then the type of seating die that you use.
 
Nathan, I'm going to assume what you said about the bushing die is right and that I'm missing something but I need clarification. The fact that the neck wall thickness is not the same all the way around is a contributor to runout so now we use neck turning tools.

So theoretically the bushing style sizer aligns the outside of the case neck with the outside of the case body. This now places all of the runout of the case on the inside surface of the neck which moves the centerline of the bullet away from the centerline of the case body. So far, I think this exactly what you've already said. But now, how would outside neck turning help runout? In my mind it is the inside of the case neck that would require correction in order to decrease runout. Otherwise, we are just removing material from the outside of the neck that won't affect or correct bullet alignment, right?
 
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Hartcreek you're right that the bullet can add its own runout to the mix but I figure that it would be better if the case had .003 or less versus .007 or more if my bullet brought in an additional .005 or however much. Still a valid point though.

If you can see the ogive is off with the naked eye, that has to be the exception unless you have batman vision. I would think it would have to be .080 or more for my eye to see it. Unless it's just a damaged nose.
 
SE Hunter: When you outside neck turn, you make the necks an even thickness. Then you bushing size. That creates the neck od and body od concentricity. It also aligns the id of the neck with the od of the case since the neck thickness has been evened out.
 
Ahh. That's what I was missing. I was assuming the neck turning was done on an already sized case. That doesn't even make sense to do it that way now that I think about it. I was turning the necks on some of my 30-06 cases for a short while with a Forster hand held tool. This was when I was still using the RCBS sizer from the standard 2 die set.

I really wanted to begin to include that step in case prep for all the bolt guns I load for but I got cold feet and laid it down because there wasn't an efficient way for me to consistently turn all cases to the same spot down toward the shoulder. I felt like I may have been doing more harm than good. Actually, I wasn't even sure how far down you're supposed to go. There were different opinions on that as well so I just stopped using it and trashed those cases.
 
I may have runout but I guarantee you there's no rattling around going on in the chamber of my bolt guns. I use a RCBS precision mic to measure a twice fired, neck sized case in all my bolt guns. With the help from a competition shell holder set, there is ever so slight resistance felt as the bolt is being locked.
 
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