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Question: Reamer Dimensions vs Chamber Dimensions vs Case Dimensions

I do not know of a company that makes a die for use with gauge pins. I Have put a small O ring on a gauge pin, then used the Lee collet sizer which produces shockingly straight necks. Granger and other companies make gauge pins. The gauge pins come in .0005 and .0001 graduations.

You can create your own graduated set of gauge pins to check the Inside dia of the cases before seating the bullets in .0001 increments. This enables you to have infinite control over the "bullet grip".

Gauge pins are not tapered on the end like expander mandrels.
 
I do not know of a company that makes a die for use with gauge pins. I Have put a small O ring on a gauge pin, then used the Lee collet sizer which produces shockingly straight necks. Granger and other companies make gauge pins. The gauge pins come in .0005 and .0001 graduations.

You can create your own graduated set of gauge pins to check the Inside dia of the cases before seating the bullets in .0001 increments. This enables you to have infinite control over the "bullet grip".

Gauge pins are not tapered on the end like expander mandrels.
VinceNule: I am not quite following your process. So you are saying that even when the case neck has been cut to, or for thickness with the neck being held by a mandrel during that process, On my 6mm/;280AI I cut my cases all to the same length, Then cut the necks for thickness. After that I then start the process to reduce the necks from 7mm to 6mm. in 4 steps to achieve the neck OD & ID of the neck. I don't use an expander ball in any of the process. I do have a bullet seating die cut by my reamer to seat my bullets with. I think I have held my bullets and case inline at that time. I am using a 21st Century neck cutting system to cut my necks with. So the neck is held inplace by a mandrel.
Otherwise you are saying possible reduce the neck to a smaller dimensions, and expand to create the proper neck tension with a mandrel, and straighten the neck, which I can do. Too me is seem I am working my brass more than needed. I have the mandrel bodies and mandrels to do that work, I believe😁. I also have a ardor press if needed and mandrels in .001" sizes.
I felt or feel that I am starting off straight that should be straight when finish. 😄
Pleease advise. I don't get mad, I just get even. 🤣 You have gotten me to thinking!
 
Mike, The use of the mandrels in various sizes is in reference to using with the Lee Collet dies, and checking the inside dia of the case mouth, once it is sized. Sorry for the confusion. Never underestimate just how straight the lee collet sizer sizes the neck.

Your turning system is the same as I use.

After sizing the case with a bushing die, check the run out on the neck. Running the sized case through a mandrel die, straightens out any mis alignment, and when used along with the Forster die that has been honed at the factory, you have some incredible precision ammo. There is a lot of ways to skin a cat, just use your Concentricity gauge to check loaded ammo. Some expensive dies are not worth a darn. Also, the use of a Body sizer, then sizing the neck with the Lee collet die is amazing in how straight the ammo is. These are two systems that have proven to work.

Mike, when I have made bullet seaters using the chamber reamers, I usually ended up lapping out .0015-.002 to give clearance to help in the brass "spring back". Your gunsmith may have already done this. Otherwise, the seater die is often used as sizer die, which hurts nothing but gets tiresome. This issue usually occurs when the brass is work hardened from 5+ firings where the brass was sized down, then springs back to some degree.

I never get mad over discussions on methods, this is how we learn. All I have learned has been from older and very experienced gunsmiths and shooters. We pass on the knowledge from shooter to shooter, and hopefully, we never quit learning.
 
I do not know of a company that makes a die for use with gauge pins. I Have put a small O ring on a gauge pin, then used the Lee collet sizer which produces shockingly straight necks. Granger and other companies make gauge pins. The gauge pins come in .0005 and .0001 graduations.

You can create your own graduated set of gauge pins to check the Inside dia of the cases before seating the bullets in .0001 increments. This enables you to have infinite control over the "bullet grip".

Gauge pins are not tapered on the end like expander mandrels.
Porter Precision Products, Ken Porter.
Uses gauge pins. Good guy, innovator and quality machinist.
 
I do not know of a company that makes a die for use with gauge pins. I Have put a small O ring on a gauge pin, then used the Lee collet sizer which produces shockingly straight necks. Granger and other companies make gauge pins. The gauge pins come in .0005 and .0001 graduations.

You can create your own graduated set of gauge pins to check the Inside dia of the cases before seating the bullets in .0001 increments. This enables you to have infinite control over the "bullet grip".

Gauge pins are not tapered on the end like expander mandrels.
@VinceMule
So I have stumbled down this path in recent days. Lee collet neck sizer and a set of gauge pins.
How are you controlling your bullet grip in infinite control? Lee sizer is one size, you get what you get, unless you go back in with a mandrel?
Your experience may save me some steps.
 
I modify mandrels, and buy mandrels from two different sources. Lee can sell you additional mandrels smaller/larger graduated in .001. This size adjustment can be too coarse. Std gauge pins can be used with an O ring in the lee collet sizer, but they are not tapered on the end like Porters products are.

Lee collet sizers/ Porter collet sizers along with the Forster honed to size dies produce the straightest ammo I have tried. Of course, one guy can only try so many ways, which is why discussions like this are so important.

Having a run out gauge is critical in evaluating your "system".
 
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@VinceMule
So I have stumbled down this path in recent days. Lee collet neck sizer and a set of gauge pins.
How are you controlling your bullet grip in infinite control? Lee sizer is one size, you get what you get, unless you go back in with a mandrel?
Your experience may save me some steps.
If you remove the Lee mandrel, drop in a gauge pin, it will just fall through the die, so put an O ring on top to hold it in

Non tapered gauge pins can be purchased from Granger and Other companies. Two grades of gauge pins:

.0005 incremnts

.0001 increments
 
I am getting lost here. 😁
Mike, The use of the mandrels in various sizes is in reference to using with the Lee Collet dies, and checking the inside dia of the case mouth, once it is sized. Sorry for the confusion. Never underestimate just how straight the lee collet sizer sizes the neck.

Your turning system is the same as I use.

After sizing the case with a bushing die, check the run out on the neck. Running the sized case through a mandrel die, straightens out any mis alignment, and when used along with the Forster die that has been honed at the factory, you have some incredible precision ammo. There is a lot of ways to skin a cat, just use your Concentricity gauge to check loaded ammo. Some expensive dies are not worth a darn. Also, the use of a Body sizer, then sizing the neck with the Lee collet die is amazing in how straight the ammo is. These are two systems that have proven to work.

Mike, when I have made bullet seaters using the chamber reamers, I usually ended up lapping out .0015-.002 to give clearance to help in the brass "spring back". Your gunsmith may have already done this. Otherwise, the seater die is often used as sizer die, which hurts nothing but gets tiresome. This issue usually occurs when the brass is work hardened from 5+ firings where the brass was sized down, then springs back to some degree.

I never get mad over discussions on methods, this is how we learn. All I have learned has been from older and very experienced gunsmiths and shooters. We pass on the knowledge from shooter to shooter, and hopefully, we never quit learning.
I finally fallow what you are driving at. I felt that by setting up and steps I do should make the reloads straight., I'll will have to check it out.
One thing I have felt is that not by cutting your neck to thickness or cutting the uneveness out ot the neck created problem at the time firing the round off.
How I see is if the case neck isn't trued up on the outside and it hitting the chamber wall would kick the bullet out of alinement some. Others say not, but I don't agree. Each of us think about problems in different ways. Which is good and letting others know with what you come up with is better.
I felt like that the process I have changed too would do the jod and not working the brass and more than needed. I am set up to anneal after each firing of the case, then sizes and bump case. Place the case into a case length cutting equipment to set the case length so they are all the same. In the sizing I set neck tension with a bushing die. The bushing die is set up per Redding requirements which allow the bushing to center on the neck. I haven't as of yet check for springback. Will do after getting everything set up again. I'll use the runout gauge to check and see where I come up with. I will compare the different steps. Including at the range.
I'll give it a shot and reduce the neck down another .001" or so and use a mandrel to expand the neck back to the neck tension I am after. 🤣 Everything is subject to change. I'll do a comparison and see what comes up. It will sometime before I get to it. My plate is full this spring, and traveling is in store. I have granddaugther, and a grandnephew graduate from college this year. Both are degrees that are useable, and can earn money. Not in basket making. 😁 One in the South and one in Mexico-North. Plus going to see some friends.
I do appreciate the imput and see things a little different.
 
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