30 Gibbs case forming

woods

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Just picked up a project for a friend that is a 30 Gibbs. He has 18 old cases

DSC00995.jpg


but asked me to figure out how to form new cases. From what I have read the method is to expand the neck to 338 and then form a false shoulder that has a crush fit in the chamber, load a medium load with the bullet into the lands and fire form.

The dies I have that I thought might work are:

Lee Universal Expander
338 win mag Lee Collet
338 RUM Competition bushing neck die
30-06 FL die
30-06 Lee Collet
30-06 Redding Type S bushing neck die

So my initial concept was to expand the mouth of the case to 338 or so and force the 338 Lee Collet mandrel into the neck and neck size just the right amount to match the fired cases shoulder position.

But the 338 mandrel does not do a good job and I don't think this will work

DSC00990.jpg


the mouth is crooked and the bulge is on one side. I did liberally lube the neck during both processes (expander and collet mandrel).

Anyone with any experience?
 
I ran a 30 Gibbs for a few years and the best way I found to form brass was to neck down 35 Whelen cases giving a false shoulder and then fireforming with a good stout 30-06 load. I'd have to check but I still might have some 35 Whelen brass sitting around somewhere.
 
I've owned a 30-06 JDJ which is basically a Gibbs with a sharper shoulder.

Best way to fireform cases is to seat a bullet long enough to hard engage the lands, even if you have to load them single shot. Then fireform using an appropriate load.

No need to mess with necking up and then necking back down. Below is a copy of what SSK provides with their 30-06 JDJ.

280JDJFireforminfo.jpg


Regards,

Rog
 
I ran a 30 Gibbs for a few years and the best way I found to form brass was to neck down 35 Whelen cases giving a false shoulder and then fireforming with a good stout 30-06 load. I'd have to check but I still might have some 35 Whelen brass sitting around somewhere.

Thanks dodgefan and you too Buttermilk

If you are necking down a 35 Whelen, which die did you use and did you have to do an interim step? The reason I ask is that in necking down a 375 Ruger case to 30 caliber for a 30/375 Ruger I have to use a 338 RCM FL die and then a 338 RCM Neck die to get the neck down. If I go straight to 30 caliber it will compress the case and crush it. I think the normal amount recommended to downsize is no more than .035" or so.

Going from the 35 Whelen to 30 caliber is possible in one operation? So I suppose I could use a 338 win mag or 338 RUM neck sizer and then a 30 caliber.

I found some 35 Whelen cases on Midway so getting some will not be a problem.
 
When I sized it down I didn't do anything but a straight neckdown. I bought a set of 30 Gibbs dies from Huntington Die Specialties. At first I used 308 win dies because of the slightly sharper shoulder.
I tried the seat a bullet out well into the lands method and it worked but I had more problems with the case stretching just above the web like that.
 
I use 35 whelen brass for my 338 gibbs and 30 gibbs. For the 30 I take it down in two steps to 338 and then to 30. I seem to get better longevity because the neck is not getting blown out so far to meet the chamber. I neck it and chamber until I get a good headspace off the shoulder. Then set my dies to that length.
 
I use 35 whelen brass for my 338 gibbs and 30 gibbs. For the 30 I take it down in two steps to 338 and then to 30. I seem to get better longevity because the neck is not getting blown out so far to meet the chamber. I neck it and chamber until I get a good headspace off the shoulder. Then set my dies to that length.

So do you use 338 and 30 caliber neck sizing dies?

I hate to be PITA but like the idea of the 35 Whelen brass and need to be specific on the dies. If I need other dies then I can order them when getting the 35 Whelen brass. For 338 I have:

338 win mag Lee Collet
338 RUM bushing neck sizer

30-06 Lee Collet
30-06 FL regular expander ball type
30-06 Redding Type S Neck sizer

300 win mag Lee Collet

Don't mind getting more dies since it is on my friend's tab and he has enough to not worry about it.

Thanks, we're almost there
 
Woods....I use .270 or .280 brass to form my .300 Sherman cases which are very close to the Gibbs only less body taper, sharper shoulder, and longer neck. If you open the neck up to say, .338, then partial size back to .308 just enough so that you leave a false shoulder, you don't have to mess with loading bullets. You can load 11 grs. of red dot, cream of wheat to base of neck and a little cotton to hold it all together (fire away). I have even formed them by simply sizing directly to .308 and using the same load to fireform with no stretching at the web. I believe , because of the longer .270/.280 case, the neck of the case binds at the start of the throat and acts to headspace just like a false shoulder would. I don't know if this would work in every case, but it works great in my chamber which measures 2.515". You might experiment with this a little. At worst, you might have to trim the case length slightly before you fireform, but it is a lot easier than going thru all the sizing etc. Also, you aren't going to end up with too short necks. If you REALLY want to make life easy, do what I do currently; order a hydro die from Lonnie Hummel of Hornady and all your troubles are over:D.......Good luck/Rich
 
I have a full set of hornady generic neck sizing dies. They will neck size any cartridge. I use the 338 neck sizer the bring it down to 30. Go a little at a time until you get that false shoulder headspace then lock in the die.
 
I ran a 30 Gibbs for a few years and the best way I found to form brass was to neck down 35 Whelen cases giving a false shoulder and then fireforming with a good stout 30-06 load. I'd have to check but I still might have some 35 Whelen brass sitting around somewhere.
This is absolutely the only way to do it 280 brass works well also engage in the lands u get a 30 gibbs everytime
 
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