Bushing dies or not

With a bushing die, you can adjust the amount the case neck is sized. You can set the amount of resizing of the neck by changing the bushing. Then you will get the amount of neck tension desired. You can then remove the expander button from the decapping rod.

I believe the Lee Factory crimp die for rifle cartridges is a collet crimp. Your bullet really should have a cannelure for the crimp to be effective without damaging the bullet.

I do not crimp any of my rifle cartridges that are used in semi-auto or bolt action rifles. I get sufficient neck tension from the resizing process.

The Lee Factory Crimp Die is not creating neck tension. It’s creating a crimp. Nothing more. No. It cannot be used to replace appropriate neck tension from proper sizing.

You can load accurate ammunition without bushing dies, they are not mandatory for accuracy.

They just allow you more options. If you want to turn your necks some amount and still have .002” neck tension is pretty easy with bushings, not so much with a regular die.

That said, what are your requirements for accuracy, with your hunting ammunition? More than likely regular dies and brass that’s just trimmed to length will be just fine.

Depending on the bullet, you might just want to leave the crimp die in the box though. Neck tension, in one term, is how much smaller the ID of the neck is vs the OD of the bullet.

A crimp doesn’t really do the same thing and if you don’t have a cannelure your just going to swage the bullet where you apply crimp.

KYregular said:

Could you not just use the Lee factory crimp die and back it off until you get the proper tension?

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Maybe you're thinking of the Lee Collet Neck Sizing Die. It achieves a result similar to what you describe.

I'll bet if you start with the Lee set (FL sizer, Collet Neck Sizer, Seater) you'll know much more before that set of dies becomes a limit on your accuracy.

I am new to the neck bushing die. I do not know if it helps accuracy or not. I does not seem to hurt. But it is fairly expensive when you include the bushing and the possibility of having to try several bushings.

I think the collet crimp die squeezes the case down and then the diameter is established when the expander plug is pulled out? So you could change the diameter of the expander plug? But your are working the brass more and who knows how it might come out in terms of straightness. I did not get a good feeling looking at the little collet and the machining of the die. But the gun I load for now with the collet die shoots just fine.

Even though I have and have just started to use a neck bushing die I am do not believe it makes much difference. I found a used Redding Competition die set at half price for my 6 mm so I tried it. I also changed scopes. And seated the bullets out a little further. My group size went down a little but it could be random, the scope, the dies, or my shooting was better that day. It was not a big change. Both before and after was less than MOA for the 3 shot groups I shoot.

I like the die not for the neck tension but on the hope that the expensive die set might make loads a little more concentric and straighter. And I had some extra money I wanted to spend at the time. Then I had to mike the bullets and the cases I wanted to use and order a neck bushing. And hope it was the correct one.

What I am in love with is the competition bullet seating dies. Bought them for 2 of my 3 handgun calibers also. I will have them for everything I load for eventually.

Buy the best die set you can afford up front and then do not worry about it. It is most likely your shooting.

I've pretty muck gotten to the point where all I'll buy are FL sizing bushing dies as I don't like over sizing my case necks, then expanding them back out. I'd rather minimally work my brass. I FL size to my chamber's headspace specs using die shims to adjust the amount of setback.

I use the bushings to save over sizing my case necks, I like using on .002 to .003 sizing for most of my rifles. A couple bushings per caliber help to maintain that with varying manufactures case neck thickness.

I avoid crimping anything in a rifle caliber, neck tension is usually enough.

Bill M. said:

I am new to the neck bushing die. I do not know if it helps accuracy or not. I does not seem to hurt. But it is fairly expensive when you include the bushing and the possibility of having to try several bushings.

I think the collet crimp die squeezes the case down and then the diameter is established when the expander plug is pulled out? So you could change the diameter of the expander plug? But your are working the brass more and who knows how it might come out in terms of straightness. I did not get a good feeling looking at the little collet and the machining of the die. But the gun I load for now with the collet die shoots just fine.

Even though I have and have just started to use a neck bushing die I am do not believe it makes much difference. I found a used Redding Competition die set at half price for my 6 mm so I tried it. I also changed scopes. And seated the bullets out a little further. My group size went down a little but it could be random, the scope, the dies, or my shooting was better that day. It was not a big change. Both before and after was less than MOA for the 3 shot groups I shoot.

I like the die not for the neck tension but on the hope that the expensive die set might make loads a little more concentric and straighter. And I had some extra money I wanted to spend at the time. Then I had to mike the bullets and the cases I wanted to use and order a neck bushing. And hope it was the correct one.

What I am in love with is the competition bullet seating dies. Bought them for 2 of my 3 handgun calibers also. I will have them for everything I load for eventually.

Buy the best die set you can afford up front and then do not worry about it. It is most likely your shooting.

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There is no expander ball in the lee die. The collet smashes the brass onto a mandrel. You can get different sized mandrels to adjust neck tension.
Another way to do controlled sizing is to pull the expander rod out of a standard die and then expand the necks with guage pins after sizing.

Neck bushing dies were really designed for riffles with tight neck chambers. In these chambers the necks may only expand .002 - .004 after firing. In a factory chamber, the neck may expand .010 - .012 or more. the bushing were never meant to resize the necks more than about .004 - .006. Therefore, they induce a lot of neck run-out when you size more than that. Guys that choose to use them with factory chambered riffles have to size them using 2-3 neck bushings that decreasing in size so they are only moving the neck .004 with each step. Bushing dies are great for the right application

Most standard dies size the neck by squeezing it down several thousands too far and then pulling a expander ball back through it to set the final neck size and tension. This induces lots of neck run-out and over works the case necks (reducing case life). If you are spending $90 for 100 cases, case life is important to you. The most economical way to size a case neck fired from a factory chambered riffle without inducing neck run-out or overworking the case is with a LEE collet neck sizing die. It uses a collet to size just the neck onto an internal mandrel (which sets the neck tension) and never touches the rest of the case. You can set more neck tension by reducing the size of the mandrel. Then, you simply run the case through a F/L body die to bump the shoulder back .001 - .002 and full length size the rest of the case. Many long range competitive shooters use this method because run-out effects accuracy. If you are hunting in 100 - 200 yard range it won't make any difference. If you are shooting long range, it does.

There are multiple other ways to size cases and necks using different sized expander mandrels, different sized expander balls, foster dies with honed necks, etc.. to set neck tension but that might take several paragraphs. However, feel free to PM me if you want some further explanation.

KYregular said:

Thanks, that may be what I do. Just order the Lee Collet die, or maybe even the set with both collet and full length sizing die. If that's the case I guess you just remove the expander from the full length die.

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The issue is as you cannot use the mandrel inside the neck sizing die to open the necks up I asked that question initially and was told that it would break if you did that. Depending on where you're ordering from Sinclair has a holder and a mandrel cheap enough that if you're adding it to your order it would only be another 20 or so dollars and you would have a Precision mandrel for expanding the necks.

Most bottle neck rifle dies are going to have a decapping pin and expander that is below the neck as it is sized. Like, from left to right, #1,2&4.

The Lee collet die is the 3rd one and as above the case is squeezed around the mandrel. The last one on the right is a Sinclair expander only.



The “undersize” then pull the expander back through is the most used because it is one operation that will give the most similar ID of the neck with most any case.

If you use a bushing, that reduces the OD by a certain amount, it’s pretty obvious that neck wall thickness uniformity is critical. If your neck thickness varies by .003 and you are sizing for .002 neck tension, some will have none. Because an “o” with a thicker wall, “O” but the same outside diameter has a smaller inside one.

.003 variation in brass is not unheard of and would be phenomenal if one could maintain anything close to that across the board, with different lots, much less manufacturers. In other words bushing dies are less than useful on brass that doesn’t have consistent wall thickness in the neck.

Walkalong said:

Or the 21st Century, both are very good.
View attachment 905116

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I have the 21st century but I think the Sinclair is cheaper although I just checked and they had a huge price increase on theirs

KYregular said:

reloading 300 win

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KYregular said:

just trying to figure out if the cost of the high end dies are worth it for a hunting round

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All thats needed is a standard 2 die set from RCBS.
Order the correct shell holder also.

KYregular said:

Thanks, that may be what I do. Just order the Lee Collet die, or maybe even the set with both collet and full length sizing die. If that's the case I guess you just remove the expander from the full length die.

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You want a FL "Body" sizing die, Not a FL die. The difference is that a FL die sizes the case and the neck. An FL body just resizes the case and bumps the shoulder back but doesn't touch the neck. You will have the Lee collet die that will size the neck.

Again, most will just use a the FL sizing die to resize everything and call it a day. However, if you want to reduce case run-out and not overwork your brass, a FL body die to bump the shoulder and Lee collet die to size the necks is the way to go.

Ruger 15151 said:

Lee collet die to size the necks is the way to go.

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Really? https://www.thehighroad.org/index.p...e-bumping-down-shoulder.866034/#post-11452923
Have you solved your problem?


Its said to provide .001" neck tension. Not enough for a heavy recoiling rifle. Imo.
https://support.leeprecision.net/en/knowledgebase

The Mandrels for the Collet Dies are made to .002" to .003" under nominal bullet diameter as there is about .001" to .002" of spring back. When the case neck is finished being sized, we want the case neck to be .001" under nominal bullet diameter.

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A smaller mandrel may be needed?

There is a learning curve.


Fyi- i dont own one, never will.

Question though, can I just remove the decapper and expander ball
from say, my rcbs die and body size, then run the case thru the Lee Collet die?

Late night edit: I just realized the above method would put WAY to much neck tension on the case, hence the need for a body die.

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You could also use an expander like that last one in #13.

But yes, with most cases and decapping pin expanders, you will have a smaller than ideal neck ID if removed, for the same reason I mention in #13.

If your necks are turned to a certain dimension though, they could all be perfect without an expander as long as they have no imperfections on the ID requiring a mandrel to iron out.

The same goes for buttons though, you can actually just look at your die as a single button size. It will size one specific neck wall thickness to one specific neck ID. They don’t do anything magical, just let you change the actual sizing portion (button) for what wall thickness in brass they can work with and/or the amount under the neck is sized to.

My idea is determine how much money and time you are willing to spend per round. Let that be your guide. I shoot 500 YDS or less no matter what. My hunting is 100 YDS or less. With those parameters in mind I use the Lee die set with the collet die for most bottle neck ammo. I also anneal every three reloads to keep neck tension under control. Then buy the best bullet for your use. Working on the brass and using a crappy bullet makes no sense either. Finally I check bullet runout by rolling the round across the bench. Any wobble and the round is pulled and redone. I will never win a bench rest match but I will load and shoot more rounds in the same time frame they put into the hobby.