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Neck sizing question

i have read that some are not sizing the inside of the neck when resizing the case. I know that I can remove the expander ball and size and deprime the cases.

The question I have is when I tried it on my 6.5 Cm brass it took way too much force to seat the bullet. My fear is that I could crush the shoulder or cause higher pressure to get the bullet down the barrel.

What are you guys doing
 
The question I have is when I tried it on my 6.5 Cm brass it took way too much force to seat the bullet.
You are using your bullet as an expander. Measure the OD of a fired case neck, measure the OD of the case neck after sizing with the expander removed, and measure the OD of the case neck after you seat the bullets. I've seen some dies recently that undersized the case neck by 0.008-0.010". Way excessive. Either:
1. hone the FL sizing die neck to the correct diameter
2. put the expander back in the die
3. Use a mandrel expander to correct the excessive undersizing your die is doing

Or you could start using a bushing die. If you don't anneal, the extra work your sizing die is doing to the case neck will make it crack sooner from work hardening. I would be more worried about the deformation you could be doing to the bullet with your current setup.
 
You are using your bullet as an expander. Measure the OD of a fired case neck, measure the OD of the case neck after sizing with the expander removed, and measure the OD of the case neck after you seat the bullets. I've seen some dies recently that undersized the case neck by 0.008-0.010". Way excessive. Either:
1. hone the FL sizing die neck to the correct diameter
2. put the expander back in the die
3. Use a mandrel expander to correct the excessive undersizing your die is doing

Or you could start using a bushing die. If you don't anneal, the extra work your sizing die is doing to the case neck will make it crack sooner from work hardening. I would be more worried about the deformation you could be doing to the bullet with your current setup.
Thought about doing that too.

Figured I would ask before it jump in.
1) Remove the decapping die from the FS dies
2) Size using the FS and bump the shoulder by 0.003" (the neck of the case would be sized down but not expanded.
3) Use the Mandrel die to expand the case neck. This step you are not doing. I use a Sinclair mandrel case neck expanding die. https://www.sinclairintl.com/reload...ls/generation-ii-expander-dies-prod38807.aspx
Ok, got it now. I must of missed the Mandrel die part..

Makes sense.
 
I do not "neck size' meaning only sizing the neck not the body. I full length resize.

If you are using a standard sizing die (either neck or full) I believe you should not remove the neck expanding assembly because it might create too much neck tension thus requiring too much force to seat the bullet which seems to be the case in your situation. Also, the expander uniforms the inside of the neck. Standard dies are designed to be use with the expander assembly.

The difficulty becomes that the expander button can be too large or small in diameter depending on the brand of cases being used, the amount of firing and resizing (i.e., hardening). Thus, requiring too much force to pull the neck through the button or the other extreme, too small to effectively uniform the inside of the neck.

Some use brushing dies or mandrels which is very effective in controlling neck tension. While not optimum but it works, at least for me, I've purchased a few extra expander assemblies, polished them and resized them in .001" increments so I can obtain the desired neck tension by substituting the appropriate expander button assembly.

Many ultra-precision shooters anneal and turn necks, but I don't do either since I'm able to meet my precision varmint hunting needs using the aforementioned approach.
 
i have read that some are not sizing the inside of the neck when resizing the case. I know that I can remove the expander ball and size and deprime the cases.

The question I have is when I tried it on my 6.5 Cm brass it took way too much force to seat the bullet. My fear is that I could crush the shoulder or cause higher pressure to get the bullet down the barrel.

What are you guys doing
I use a mandrel as my final step
 
You'll want to get various sized mandrels/bushings for setting the neck tension. It's kind of an expensive proposition, but it's the only way that I have found to set neck tension.

Different manufacturer's of brass seem to have various kinks when it comes to what combo of mandrel and bushing work to give the desired tension. Just my 2.............
 
Do the Fired, sized, loaded neck measurement mentioned above.
It will tell you what work is being done to your neck.
FL sizing with a bump also has the tendency to form a slight donut at the neck/shoulder where the brass tries to 'round the corner'.

I use a body only die and a Lee Collet Neck die with a polished down mandrel.
I reamed a Small Base Die neck to .2505" with a carbide reamer for my gasser (.223 and 22 Nosler).
Polished the fresh cut corner inside the die a little.
Very slight neck sizing in the FL/SB die now. As purchased it sized the neck down to 0.243". Way too much.
Then into the Lee die to straighten the neck from the inside.
Loaded neck is 0.2515" - 0.2525" depending on brand (Nosler or Dogtown brass)
 
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I don't know if it has been mentioned, but chamfering is also an experiment that seems to have various effects on the seating pressure. There are different angle chamfer bits out there. That angle seems to make a world of difference..............If you aren't chamfering/deburring, you're just wasting components.
 
I Take the neck sizing very seriously. I use a Lee Collet die for neck sizing because
I've never found any other die that produced as straight and true necks as the Lee
including Wilson and Redding. I then got a 21st Century Expander set to expand to
either 2 or 3 thou smaller than bullet diameter or simply sand down the Lee rod to
what I want to give the neck the right amount of grip.
Good Luck whatever way you pick
 
have read that some are not sizing the inside of the neck when resizing the case. I know that I can remove the expander ball and size and deprime the cases.

The question I have is when I tried it on my 6.5 Cm brass it took way too much force to seat the bullet. My fear is that I could crush the shoulder or cause higher pressure to get the bullet down the barrel.

What are you guys doing
A lot of FL Sizers without expander ball, will size the neck. .001 to .003 Smaller than with It, use an Expander Mandrel
 
You can pretty much modify or customize any and all parts to fit your needs..
I agree here with the forum that ( Nothings quite right out of the box )
but its not hard to fix or modify everything to fit your needs.
I got a bunch of gage pins I ground and created neck manderls from on the cheap.
 
And 0.002 neck interference isn't a hard fact of accuracy. Some cartridge/load and/or component combinations may benefit from more or less interference fit. Function/safety may also need to be considered as a part on neck tension. I have a 204r that with 39 gr Sierra shoots best with the 0.004-0.005 neck tension that results from a stripped FL sizing die, it takes some neck lube to get bullets to seat smoothly in New brass.
 
I turn mandrels that work in Lyman M dies. Just how I started,there's dies available now that use "over the counter" gage pins.

Reason for post;

When working on a new rig/barrel,have settled in now on using two sizes for initial testing.... .002,and .004" interference. It's far enough apart that it gives you a pretty good idea on where that particular chamber/bullet is gonna be happiest.

Once in awhile,it'll dip below the .002",but have never had one needing more than .004.....

The .004" interference means the mandrel is smaller. If the new rig leans more towards this size,we can take the larger mandrel and start skimming "tenths"(.0001) looking for a sweet spot. Good luck with your project.
 
With the expander ball in the die, it will undo on the upstroke of the press some of what the bushing did with regard to sizing the necks down on the downstroke of the press. The problem may sometimes be that pulling the expander ball out through the neck can cause runout. So some folks remove them. However, you can't solely remove the expander ball/decappin pin and necessarily expect the die to size necks the way you'd like them. For example, the bushing may be too small to be used by itself without the expander ball to open the necks back up a little on the way out, or perhaps you didn't intend to use a mandrel as a final sizing step.

Regardless, if you decide to remove the expander ball, you may need to test a few bushings to determine the correct size bushing to be used on its own without the expander ball. From your description, I'd think you might need to try a couple slightly larger bushings than were in the die to start.

Alternatively, you could simply leave the bushing the same and re-size cases without the expander ball, followed by a mandrel step to expand the necks to the desired diameter (neck tension/interference ft). In the event that the bushing was markedly smaller than necessary for the mandrel to actually do some work and open the necks back up a bit, you'd be working the brass more than necessary. It would still work, but at some point you'd probably want a bushing that wasn't squeezing the necks down more than a couple thousandths below the diameter to which the mandrel would later open them.
 
i have read that some are not sizing the inside of the neck when resizing the case. I know that I can remove the expander ball and size and deprime the cases.

The question I have is when I tried it on my 6.5 Cm brass it took way too much force to seat the bullet. My fear is that I could crush the shoulder or cause higher pressure to get the bullet down the barrel.

What are you guys doing
Sizing video by Erik Cortina and Speedy Gonzales. Two of the best. Both in the HOF.

 
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