We asked some questions to determine the difference in thinking between the seasoned benchrest competitor and the casual accuracy minded individual...

To begin, three questions were posed to get the ball rolling:

1) What type of seating die do you use (threaded or not)?  If it's
an unusual or custom die add that to your answer along with why
you use such a die.

2) What method and tools do you use to determine seating depth and what do you do when changing bullets?

3) In your opinion, how important is neck tension?  Consider this
question in terms of the degree of tension and in terms of
consistent tension from case to case.  If possible, include your
reasoning.

Six seasoned competitors responded as did a number of self identified accuracy nuts.  Names of the accuracy nuts are withheld by request (not all but enough).

Here is what they had to say - accuracy nuts first:

1) I guess I have all three, I have threaded dies from RCBS, Wilson and Lee Loaders.

I have had good luck with RCBS and some of my best loads are produced with lee loaders, but by far the best is the Wilson.  I was taught on lee loaders and then acquired a press and have stepped up to an arbor press with Wilson dies.

2) I initially set the dies with dummy rounds by trial and error then use a stoney point bullet comparator to measure case length to the ogive and use that to adjust the dies if changing bullets.

3) I think consistency of neck tension is very important.  As to the amount of neck tension I think the amount varies with the cartridge and the use it is intended for.

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1) I use both Wilson micrometer dies and Redding comp seater dies. My number one criteria (apart from making straight cartridges) is that it has a micrometer on it. I'm about to order my first set of custom dies from Neil Jones.

I don't yet have a concentricity gauge, so my preference is based on convenience. I prefer an arbor press and dies for small cartridges 'cause I can pick it up and move it over to a more comfortable place to sit. I'll usually just use the co-ax press and a threaded die for longer cartridges (.243 Winchester length and greater). Once I get a concentricity gauge, I'll start weeding out the things that don't make straight cartridges.

2) Just a Stoney Point OAL gauge. Wherever it measures to (with several repeated measurements) becomes a reference point. Unfortunately, I don't know if that point is in the lands or at the lands. Regardless, I wind up with a repeatable reference point.

3) I can only go from what I've read, I don't have any experimental data to work with. Neck tension is apparently very important. I haven't seen anyone test this, but I would imagine that the criticality of neck tension depends on whether or not you are jammed into the lands. To my untrained-in- physics mind, it would seem that the only benefit of neck tension is to retain the pressure inside the case longer to lead to a faster, more consistent burn of the powder. If that is the only benefit, then being jammed in the lands would diminish the need for neck tension as the force required to move the bullet in the neck would be relatively inconsequential compared to the force required to push the bullet into the rifling. However, greater neck tension may help ensure that the bullet is jammed into the lands straighter.

If the above line of reasoning is even close to reality, then consistent neck tension either ensures that your charge builds up to the same pressure before the bullet starts moving or the bullet is consistently placed into the lands the same way each time.

So, even if the above is a crock, it's enough of a justification for me to take the advice of other shooters and jump through the extra hoops necessary to make sure that I have sufficient and consistent neck tension, not too mention spend a few extra dollars for the force measurement option on my K&M arbor press.

As to how important it is, I haven't got a clue as to how it compares to the myriad of other factors that affect accuracy. All I know is that if I didn't care about the extra bit of consistency that I (presumably) get from it, I'd just buy a Dillon and hammer out rounds. In fact, I might just start buying the bulk ammo from Cabela's and enjoy shooting at rocks.

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1) I use a threaded, Redding Competition die...I started with the manual Wilson die.....worked fine but the Redding is easier to adjust, quicker and I think just as precise 

2) I use the old fashioned bullet in a slightly tight neck, chamber it and carefully remove it.....4-5 times to get an average, usually repeatable within 002-003 if the neck isn't too loose. Redo this for each bullet change. 

3) I believe neck tension is a factor, but I don't see any differences between 258-2585-259 necks in my 262 rifles...haven't looked

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1) I use a Redding comp. seating die threaded. 6mm PPC.I use the Redding comp. die because of the sliding bushing that centers the points and ease of adjustment.

2) When I first started out I used a Stoney point gauge and then learned to split the neck apply point long and chamber cartridge, remove and measure. I have never changed bullets. I stated out with Barts and still using them.

3) I always felt that consistency was most important than the amount of tension. I had always heard about pros just stating bullets and letting chamber seat the points. So I went the consistency route.

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1) I use threaded dies, and as a pistol shooter a progressive press, carbide sizer and a carbide taper crimp in the last slot.  When I load for my custom AR-15 target rifle, Les Baer .223 Super Varmint, I weigh charges, and use a threaded RCBS competition seating die allowing micrometer adjustment of the seating depth, and a single stage press.  I don't seat into the lands, still use the listed C.O.L., but am aware of the potential accuracy improvement.

2) I load to the prescribed C.O.L. in the load data book.  If I change bullets, and the C.O.L. changes I reset the seating die.  If I were to seat to the lands, I would seat a bullet into an empty unprimed fire formed case  a little long, and try to close the bolt without a lot of pressure.  I would keep moving the bullet down a few thou at a time in my seater die till the bolt closed with just a bit of a bind, all the time looking at the marks made by the lands on the bullet.  With the bullet just touching the lands, I would start testing group size as I seated deeper into the lands, and just off the lands in 5 thou increments.

3) When you whack the tail end of a bullet with 50,000+ PSI I do not believe neck tension has a dang thing to do with accuracy.  What I do feel is important is that there is enough neck tension to keep the bullet from moving in the neck before firing and that everything remains fairly consistent.  I.E. Same type case, sized the same, same charge weight of powder, primer, seating depth, and the bullet seated square to the case, etc. 

Let's see:  A bullet that has base surface area of say a typical .308 has an area of Pi x radius squared or .154 X .154 X 3.14159, or 0.07450594844 square inch.  If it takes for example 15 lbs. of force to seat a bullet, it would take approximately the same to un seat it.  By my calculations, to reach 15 lbs. of force it would take an internal pressure of 201.326 PSI to exert a 15 lb. force on the end of that bullet.  (15 divided by the surface area of the bullet, 0.07450594844 = 201.326)  Seems to me that the bullet is going to move just slightly below that 50,000+ PSI developed in modern cartridges.  (said with tongue in cheek and hope my math is close) Probably before the primer finishes going pop. 

Gulp... 

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1) I use a Forester micrometer seater on my 6br.  On my 223 I use Lee Collet dies. 

2) I use a full length sized case with a tiny bit of neck tension, seat the bullet very long, insert into the barrel very gingerly and do this about 3 times and put the calipers to it each time and average.  That’s on the 6br. On the 223 I have a barrel gizzie that my smith made for me that is just the neck and shoulder of the reamer, with 1/4 of the area milled away so you can see what you are doing. 

3) I think it is very important, but at this point of my “accuracy shooting career" I am at a loss as to how to obtain anything consistent.  I personally like to run with a very light neck tension.  I generally seat the bullets long and let the lands determine the exact OAL. 

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1) My seating dies as of now is a threaded Redding die I use this die because I’m new to highly accurate shooting/reloading and do not own an arbor press now and at the time of die purchase wasn’t sure exactly how the non threaded dies worked.

2) I base my seating depth off of jam measurement to get jam I take a sized case with no primer or powder and seat a bullet very long I then chamber the round in my rifle and measure from base of case to ogive of bullet using Davidson’s attachments on a dial caliper I write the measurement down for that bullet I put the same bullet in my press and lower the handle and turn in my seating depth adjuster till it touches the bullet then on my first loaded round ill adjust the depth stem till I get .003 shorter or what ever measurement I’m looking for. I have one dummy round for every different bullet I have ever shot so I have a reference to go back to as well as written documentation.

3) Neck tension seems to have varying importance from powder to powder in my particular case I was using light neck tension with the powder combination I was using and getting decent groups, I went with a little more neck tension and groups improved noticeably as far as consistency from case to case I really have no way of checking that other than feel when I’m seating so if I feel a noticeable difference when seating whether it be stiff or light pressure I mark the case and see what it does at the range compared to others.  

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1) Wilson, not threaded.  Influenced by the Sinclair catalog.

2) I began about a year ago using a Stoney Point tool and a 6” Caliper with the Stoney Point adapter.  1 week ago I took the firing pin out of my new Kelbly and put in a case with bullet and basically gently jammed the bullet into the rifling.  Difference was .020” between the two methods. Using Bruno’s New 68gr 00.

3) To answer your question ‘I don’t know” I’m new and I am doing what I believe is good advice. Since I have not yet competed in my first match, and my Kelbly is only about 6 mo old. As a beginner I have been reading a bunch (your site every day at Noon) and PS (Precision Shooting) and have gravitated to what I believe is the middle of the road, right now. I’m a cautious reloader.  The necks are .0086” thick Checked in 8 places with a Mitutoyo tubing mic.

I am using Vitavouri N-133, 28.5 grs I understand the Vitavouri likes neck tension.  I am using .003” reduction sizing as this is what was listed in the Sinclair catalog along with speaking with ‘The Guys’ at Wilson. I am using a Harrell full length resizing die to bump the shoulder with Wilson bushings.

I turn the necks with a ‘Pumpkin’ set up.  I bought his mini lathe and the pumpkin neck turner.  Why?  I was referred to your site to look under accessories. ‘Benchrest Toys.’  I have a .262” neck and turn to .0086”wall thickness using Lapua .220R brass from Bruno’s.   So far with my new Bruno 00, 68 gr bullets I am able to shoot in the 1’s.  But this will change with wind, mirage, & only 7 minutes, etc.  1st match 2/25/06 at St. Louis Benchrest.  OH Boy! Hope this helps.

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 1. I use both a Redding competition bullet seating die (threaded) and a Wilson micrometer top bullet seater.  Redding is used in reloading room while Wilson hand seater is used primarily when I'm reloading at the range. I prefer the Redding competition bullet seating die because I get less runout than with the Wilson seater.

2. First, I determine the "jam" length by inserting a bullet long into an unprimed case and chambering it.  I use a Starrett dial caliper and Davidson seating depth checker to measure from the base of case to the ogive of the bullet and record this as the "jam" length.  I do this a couple of times to check for consistent measurements.  Then I back off the jam length a few thousands at a time and see what seating depth my rifle likes with the particular bullet being used.  Most of my loads have the bullet just about .010" into the lands.  When I change to a different bullet, I repeat the same procedure over again.

3. I have tried using various neck tensions from .001 to .003 and could not discern any appreciable difference in group size at the target, at least with my live varmint rifles. What I do try to achieve, however, is consistent tension, usually about .0015 tension. No particular reason why I use this tension other than it’s easy to seat bullets and it’s sufficient to hold the bullet from sticking in the lands if I need to extract a live cartridge from the chamber.   It's been my experience that the more consistent I can make the ammunition, the better performance (smaller groups) I get at longer ranges (e.g., 500 yards), so I try to make not only the tension consistent but also case weight, seating depth, powder charge, etc. consistent from case to case.

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1) Exclusively Redding Competition Dies with TiN bushings in a Rock Chucker press.   Although I read most everyone uses the Wilson type, I found them to be fiddley little devils due to their size and the fact that they move about a lot. This said, I do not have big hands nor any condition preventing me from using them.   I have found the Redding dies to be very good and when a loaded round is run over with the NECO tool, the little GEM dial does not move. From that and that alone, I concluded that the Wilson type of die could not be any more accurate. I have no science to back this up however and it is just an opinion.

2) Given the puritans, dare I say it?  It is only an opinion after all and opinions are but that. They are not facts.   I take a prepared case, gently run it over an expander mandrel, drill and tap the case head to accept the Stony Point tool and go to town. I use the tool gently with a Dewey rod down the barrel and I think the feel is quite good. New barrels with sharp lands are easy compared to those with many shots through them and I can get 3 measurements the same with a little practice.  This is what I was taught nearly 10 years ago when I started shooting. I have always done this and it works for me.    I have also used the method of seating a bullet long, closing and opening the bolt and measuring the length to ogive, with the Stony Point tool.  I have found that this figure is always different from the former, and I reason that this may well be due to the neck tension imparted from the sizing die onto the case neck. As the bolt is closed, the lands force the bullet aft. However, I am undecided as to whether more neck tension causes the bullet to be seated deeper into the lands or pushed further aft. I know not the properties of the bullet as to how much force it takes to engrave it with land marks as opposed to the force required to move it aft into the case.  I have tried lubing with MOLY, the inside case necks and different bushings to overcome this but too loose a bushing and the bullet stays in the barrel. Too tight.... well who knows what you are measuring? I have yet to decide how to proceed with this so more often that not use the first method.   I seldom change bullets. I speak to others (or read what others are using), buy a heap of 'the' pill to use and away I go. I think custom pills are all much of a muchness and none are really any better than the others.

3) I have no firm opinion as to how much is 'enough' at the moment. This is an area of constant discussion and I remember reading Gezy Nagy's experiments in the BR Primer about it. Other articles gave up that some used next to no tension, others 'thumb' or 'palm' tension and still others tight as the proverbial. Because of that, and in consultation with those I consider knowledgeable on the subject, I use a bushing 2 thou smaller than the chamber neck diameter. Safety is a consideration. I have used 3 thou and more but on paper, I cannot show any appreciable difference in accuracy. I can however, show higher velocities over the Chrony.   I am a firm believer that consistency is the name of the game. Consistency in neck tension is something I pay careful attention to.  I am very careful in my case preparation and am constantly monitoring case measurements, especially in the neck area. If a case measures different from the others, it gets thrown out.  Before seating bullets, I lube the necks with MOLY and can feel any difference in the seating tension I believe.  Given that I do not use Wilson style hand dies, I cannot conclude there is any less 'feel' in the Rock Chucker setup I use. But, logic would certainly have it to be the case.