Neck size tension?

[Ua26fitter]

I have a Redding Type S die that I can change the bushing size for neck tension. What would the signs be that would tell me to go up or down with the neck size bushings?
I'm currently running a .330 bushing and have loaded some rounds with the .331 bushing.
I feel that I am getting pressure a little early and maybe if I use a little less neck pressure I can get a little more powder in without the pressure.
am I on the right path?

Kris

 

[bigedp51]

Redding tells you to reduce the neck diameter .002 to allow for brass spring back after sizing.
At the Whidden custom die website they sell expander kits for their standard dies. The expander kits contain 5 expanders from bullet diameter to .004 under bullet diameter.
I have read that competitive shooters like David Tubbs is using .002 to .003 neck tension.
Also if the necks are not annealed and become work hardened you will have "more" brass spring back and reducing the neck tension.
And bushing dies work best with neck turned brass and the expander is supplied with the Redding dies for those who do not neck turn.

Bottom line there are many variables on what bushing size to use with "your" brass.

Many competitive AR15 shooters use a Lyman type "M" expander on their progressive presses.

Below you can see the main part of the expander is .003 smaller than bullet diameter. The case mouth is just barely bumped onto the larger .226 diameter part of the expander to aid seating and reduce neck runout.

If you wet tumble or any other type case cleaning that removes the carbon from the inside of the case neck I would recommend replacing the missing carbon.

Dipping your case necks in graphite powder which is nothing more than finely ground carbon will replace any missing carbon from any cleaning. It will also greatly reduce seating effort decreasing any chance of inducing neck runout with tighter case necks.

 

[Ua26fitter]

bigedp51
thanks for the reply. It looks like a bigger can of worms than I thought. Accuracy is great I'm just playing with ideas to maybe get a little more fps and even a little more accuracy. I'd also like to bring my FPS of each shot a little closer. I'm getting some swings of 50 fps or more between shots. I'm playing with powders and figured neck tension might be paying into it also.
I'm a tinker so this will give me something to play around with.

Kris

 

[bigedp51]

I'm not a fan of bushing dies used in off the shelf factory rifles with SAAMI chambers.
I prefer using Forster full length benchrest dies with their high mounted floating expanders. These Forster dies have much less neck runout than bushing dies or any other standard die.
When you reduce the neck diameter .004 or more with bushing dies you will induce neck runout. This is why you are told to reduce the neck diameter in two steps to reduce the amount of neck runout.

Bushing dies work best with tight neck chambers with neck turned brass. And if just neck sizing a Lee collet die will produce lower neck runout.

 

[Ua26fitter]

It's not exactly an off the shelf SAAMI cartridge.
I'm loading for a 30-28 Nosler. I've hand loaded for several years and was looking for something different to load and shoot. It has been an easy one to load but now I'm just trying to play with things to see how much better I can get it.
my next step will be to take some Bertram brass for a .338 Edge and push the shoulder back and form my own brass.
thanks for the replies I'm learning.
Kris

 

[L.Sherm]

You can reduce the size of bushing all you want for more neck tension, if you use the same size expander you will get the same neck tension everything else being equal. Yes you have to have a bushing that is smaller than your expander size so when you come up on the handle of the press your expander pulls through the neck and that is what controls neck tension is the bushing/expander combo when using a expander. you can control neck tension with just a bushing if you take out the expander but i highly suggest you neck turn to get them uniform and sometimes it takes a couple firings and turnings to get all the necks ironed out to the outside of the brass. Whiddens have a good read on this on there web site.

 

[Ua26fitter]

L.Sherm that is a great point I hadn't really considered. Looks like I'll have some reading to soon the Widdens page.
Kris

 

[newmexkid]

If the pressure you are referring too is primer cratering maybe you need to have the firing pin bushed. Google Gre Tan rifles. He does a great job and not expensive. He's 'fixed' 2 of my rifles and no more primer cratering. At safe loads mind you.

 

[Ua26fitter]

Mewmexkid,
I do get a slight bit but I'm also getting a small extractor mark. I know I'm at the upper end but I think I should be 1 or 2 grains more. I also understand that every barrel is going to vary. The thing is I'm getting pressure with powders that others said they couldn't get quite enough in the case to reach pressure.
I've got all winter and summer to tinker with it and learn some of the finer points of loading a custom built wild cat.
I've actually got it shooting good. .5" group with 230 Berger hybrid at 2820fps I've pushed the 215 Berger at 3090 and got a little under 1" group but the fps spread was almost 100 fps from fast- slowest. I can load the 215 Berger and get a little above 2900 with almost a .5" group. My goal is to push a 215 Berger 2950 with .5 MOA. I think it can be done with some work. Maybe better.

Kris

 

[L.Sherm]

What powder are you using?

 

[bigedp51]

Ejector marks vary with brass hardness and not all brands of brass are created equal. My point being you could get ejector marks with one brand and none on another brand.

Military Lake City and commercial made brass for the military has the hardest brass in the base followed by Lapua.

In another forum a long range competitive shooter tested his Lapua brass below until he had brass flow into the ejector. He then backed off the load several grains knowing the elastic limits of the brass. As you can see in the chart below if he had tested Remington or softer cases he would have gotten ejector marks much sooner at a lower pressure. Another method is to measure base expansion just above the extractor groove.

How Hard is Your Brass? 5.56 and .223 Rem Base Hardness Tests
http://bulletin.accurateshooter.com...r-brass-5-56-and-223-rem-base-hardness-tests/

Simple Trick for Monitoring Pressure of Your Rifle Reloads
http://www.hodgdonreloading.com/rel...-trick-monitoring-pressure-your-rifle-reloads

I'm cheap and buy bulk once fired Lake City 5.56 and 7.62 brass knowing the brass is made Ford Truck Tough.
Not only is the Lake City brass harder, the flash hole web is also thicker giving the base more radial strength. And this makes the primer pockets last longer before becoming oversized.

 

[Ua26fitter]

What powder are you using?

I've tried. H1000, IMR 7828, RL26, and recently acquired and loaded some Retumbo but haven't shot it. Could be 1 or 2 more I'd have to check my notes at home.
The 7828 has had best accuracy with 215 Berger RL26 has best velocity with the 215 Berger and pretty good accuracy but lots of crazy velocity swings. I'm getting best accuracy with 230 Berger and RL26 though but still some bad velocity swings with it under the 230.
I'm only shooting 100 yards right now. The velocity swings concern me when I decide to stretch it out won't hold the group if I'm over 100 fps from shot to shot and then some will be less than 10 fps.
I did just acquire an old school manual scale to double check my automatic electronic scale and I've found it can carry by .2 grains.
After hunting season I'll be able to spend a little more time in the details. It's not my primary hunting rifle and I've only been dabbling with it.
Kris

 

[L.Sherm]

I see your trying Retumbo that was one powder I was going to suggest RL33 would be another. I would also like to see if it was me that 20 E.S. would be max. If the E.S starts to shrink using slower powders like Retumbo then your on the right track

 

[Ua26fitter]

RL33 is actually on my short list to pick up and try.
One of the reasons I'm going to form my own brass from Bertram 338 edge brass is in hopes of stronger brass. Or atleast better than the Nosler brass currently being used. I read on this page somewhere that someone had done it and had better luck with it.
Also something I need to look at is my Chronograph. It's relatively new but is reading lower by about 150fps than what I was getting when shooting through the one my gunsmith has. Is was a little more inline with what I was expecting and the one I used for the speeds I posted in my previous post.
I'm thinking I might pick up the Labradar. I don't have much time for equipment I don't trust.
Kris