Neck tension problem

[Grimstod]

So I am working on a wildcat. This is a .308x54r Improved. Shoulder moved forward about .190 and a 40d shoulder. Barrel is a 308 and I am shooting 308 Berger 190gr VLD bullets.

I Just got in a new bushing for my custom made Redding Type S Die. Its a titanium .327 bushing. Sized brass is measuring .328 neck and a loaded bullet is .3295 on my micrometer. Yet I still do not have enough neck tension. This brass has only been fired twice. I can actually push the bullet in with my finger and the air pressure makes it pop back out.


Below is a photo of two. One is how long I seat them and the second one I pushed in farther with my finger. Very light pressure to do it too.

Here is how many I am loosing. the batch in the shell holder are good. The rest on the table are too loose.

 

[Gb300wm]

I would think bushing down 0.001-0.002". It won't hurt to have those busings. You may need to anneal your brass too. It may be springing back on you from being work hardened.

 

[Grimstod]

I have annealed this stuff and did order another bushing just for this to add even more neck tension but still no potato.

 

[Grimstod]

Maybe the Berger 190s are smaller near the ogive? Or perhaps the brass is stretched as the long bullet gets pushed in and it looses all its strength by the time it stops where I am seating them. I know I can't pull them back out without difficulty. I wish I could seat these longer.

 

[dkhunt14]

I always load .001 or .002 under loaded diameter. I use a .333 or smaller in a .338 neck gun. I use .260 in my .266 neck Dasher. I believe your bushing is not small enough. When I anneal a little too hard the tension also lightens up. Matt

 

[tuttlefarm]

Do as Matt said, but also check the diameter of the expander ball, it might be on the large size

 

[dedogs]

How are you annealing? I notice in the pictures that the discoloration on the cases is all over the place. (Some have discolored what looks to be 1/2 way down the case body). dedogs

 

[Grimstod]

Some of them were tumbled and it cleaned up the annealing marks I do not tumble my brass anymore. Now I sonic clean.

So I anneal with 700d tempilaque and a propane torch. All by hand with a drill to rotate it through the flame. I only anneal the shoulder and neck.

Perhaps I should revisit annealing.

 

[fguffey]

Yet I still do not have enough neck tension. This brass has only been fired twice. I can actually push the bullet in with my finger and the air pressure makes it pop back out.

I use bullet hold, I want all the bullet hold I can get, I do not use interference fit or crush fit; and then there is neck tension. again, I can measure bullet hold in pounds.

F. Guffey

 

[DeadEyeDick45]

My bet is the Annealing situation. You need to use an Annealer and remove that variable from the equation. I use the MRB Annealer and it works fantastic and has a money back guarantee. Contact mike@mikesreloadingbench.com . He will get you on the right path.

 

[243winxb]

If the brass has not been neck turned, your problem is, some neck walls are thicker than others. The thin wall ones doesn't hold the bullets with enough neck tension. Use a smaller bushing, with light drag on the expander to get uniform neck tension. If brass has been neck turned, still just use a smaller bushing.

 

[jlow]

OP, if you have 1.5 thousand neck tension, you should not be able to push the bullet in. The fact that you said you have annealed the brass makes me think that you have over annealed the brass. When this happens, the brass can get dead soft with no springback and what will happen is the bullet will just stretch when you push the bullet in. When you anneal by hand, you probably anneal until the shoulder/neck is red hot - that is bad stuff...

 

[243winxb]

Lube the neck outside, even with a titanium bushing. If using an expander, lube inside the neck also.

 

[fguffey]

I Just got in a new bushing for my custom made Redding Type S Die. Its a titanium .327 bushing. Sized brass is measuring .328 neck and a loaded bullet is .3295 on my micrometer. Yet I still do not have enough neck tension. This brass has only been fired twice. I can actually push the bullet in with my finger and the air pressure makes it pop back out.

I believe you should start with standard dies. There is nothing suspect about standard sizing dies when it comes to bullet hold. After you get back to sizing cases with all the bullet hold possible you can start turning necks on the outside or reaming the inside of the neck; turning and reaming can reduce bullet hold. And then I suggest you take a short course on interference fit and or crush fit.

F. Guffey

 

[DOGCAPPER]

STOP using the expander.
Turn the necks so all have the same thickness.
Buy new bushing: ( neck wall thickness X 2) + .308 - 0.002.
Do all three in order listed.

 

[fguffey]

Shoulder moved forward about .190 and a 40d shoulder.

What did that do for the case between the case head and shoulder of the case; when I move the shoulder forward I put a strain on the case between the case head and case body.

STOP using the expander.
Turn the necks so all have the same thickness.
Buy new bushing: ( neck wall thickness X 2) + .308 - 0.002.
Do all three in order listed.

I was impressed with his list of tools and measurements; I believe he needs to understand bullet hold. I would suggest a neck sizing die but that could be difficult because he is using a short case. The short case requires a short neck sizing die with enough clearance for the larger diameter case and short neck.

F. Guffey

 

[gotcha]

How are you annealing? I notice in the pictures that the discoloration on the cases is all over the place. (Some have discolored what looks to be 1/2 way down the case body). dedogs

Just a side note: Tempilac techs say the ONLY indicator able to give accurate reading when directly exposed to flame is 750 degree. (Remember, the other indicating liquids are designed to be applied to the side opposite the flame.) ......... Shelf life of 750 degree Tempilac is 6 mo. from date of manufacture. 750 degree liquid should be tossed after 6 months...... its no longer an accurate indicator.

 

[Judd]

Lay a bullet next to one of those so we can see how far down in the case the bullet is. Specifically is the pressure ring below the neck/shoulder junction? I've had bullets where the pressure ring was big enough to open the neck up and I lost all neck tension...didn't seat the bullet as deep (where pressure ring was above the neck/shoulder junction) and it would hold.

Good luck, it's frustrating when something like this is going on.

 

[Ned Ludd]

What brand of brass are you using and has it been neck turned? In my hands, unturned .308 Lapua brass necks run .338" with seated bullets. A .336" bushing is just about perfect for me, and there is no way you could move a seated bullet in those cases with your fingers. Based on the numbers you listed in the OP, is it possible that the case forming process has simply made the neck walls too thin? 0.328"/0.3295" for unloaded/loaded 30 cal brass seems to me like the neck walls might be awfully thin.

 

[Terry Altom]

Do as Matt said, but also check the diameter of the expander ball, it might be on the large size

I would ditch the expander ball and use an expander die. One more step, but you don't want the ball over expanding the neck you just reduced.