Need some very quick help on shortening case bodies

[WindTrax]

Hi all,

Hey, so the cartridge I spoke about is moving along (behind schedule unfortunately) for the rifle I am planning to take to Africa next month for plains game. As a review, it's based on a shortened 300 WSM case, necked down to 6.5mm and shortened to an overall case length of 1.825 while maintaining the 35 degree shoulder and the standard body taper.

The only wildcat case forming experience I have is making a case larger by fire forming with inert filler to get less body taper & a steeper shoulder angle, and not shortening a case body like I need to do on this one.

I got the forming die (a single die) from the smith tonight.

Here's the problem; I went to start forming cases tonight and lo and behold, when I try to push the shoulder back the necessary .300", it just collapses the case body about and 1/8 of an inch farther down the body. The shoulder just seems to not want to budge! What am I doing wrong?

Any suggestions would be much appreciated. I looked through Designing and Forming Custom Cartridges (Ken Howell) as well as Wildcat Cartridges 1 and 2 tonight, but can't figure it out. I only have a matter of weeks left and am desperate to get this setup working if at all possible in time!

 

[royinidaho]

Sounds like you're in a bit of a bind.

I have the same problem when I misadjust my sizing die and set the shoulder back on the AM cartridge. A wrinkle appears just below the shoulder.

In your situation the shoulder "has" to be pushed back. So: first try resizing wax, just light amount, and go slowly. If this doesn't improve the situation you may wish to anneal the cases to below where the shoulder is going to be.

I'm no expert with this. Suggestions are what I would attempt until....... I usually learn I took the wrong fork in the road a ways back .

 

[WindTrax]

Thanks! So far I've been using Imperial (now RCBS I think bought them) sizing wax, which has worked great for general resizing work in the past. But again, I've not done this sort of operation. Annealing: ugh, I was hoping to avoid that primarily because Ken Light has been behind on the annealer I and the smith I'm using had ordered... and time until Africa is down to under a month. Sounds like that may be the answer though...

Love to hear any/all other suggestions as time is of the essence right now and I'd really, really like to take this gun to Africa if at all possible.

Thanks!

 

[J E Custom]

Roy is right about annealing the brass first but dont go past the finished length
of the sholder (This will help support the sizing process)

The reason it's collapsing the sholder is that it sounds like the die is also
sizing the neck at the same time,this normally wont work.

Two ways that might work, Find some 270 WSM brass and try them(Same size body
as the 300 WSM but a much smaller neck.

The other is to shorten a 300 WSM die by the same amount as the sholder reduction
in length so your only moving the sholder then use you wildcat dies to finish the necks
"NOTE" you may have to trim the necks some before the final sizing step.

Ether way it will take two sizing steps to get you there ( Size the body and then size
the the necks and then trim to length.(3 Steps)

Some wildcats require 4 sizing steps.

And use lots of sizing lube but take the expander ball assembly out so it want trap
the lube and cause dimpling ,plus you will want to clean the dies when you are
through with each step.

After I posted I saw that you needed help with the annealing. It's easy hears how I do it.

1=Talk your wife or girlfrend out of a cake pan about 2'' deep.
2=Fill with water up to the level you want the annealing to stop.
3=Place 10 or 12 pieces of brass in the water standing with the necks up.
4=Take a propane torch and heat each case neck until it changes color(not red hot).
5=as soon as it changes color take a nail/stick and knock it over in the water.
6=Repeat untill done.

I hope this will help
J E CUSTOM

 

[7mmRHB]

Scott, I have done pretty much the same process that you are attempting but with a full 300 RUM case. You cannot move the shoulder back .300 with one form die, annealed or not!! My form die set has three form dies and a full length sizing die.The shoulder must be pushed back in stages from the outside so there is someplace for the brass to flow to. The third die gives you the new neck ( thats about 1/2" too long )which needs to be cut off and requires inside neck reaming at that point to get rid of the Donut at the neck shoulder junction. Now you anneal and full length size, trim to length and neck turn. The necks need to be turned because of all the added brass that flows in during the forming process. 300 WSM brass is already very thick in the neck before you even started the forming. About .018 to .020 I beleive.

GG once posted a pic of the steps in forming my 7mmrhb wildcat on LRH but I don't have the skills to go locate it. Maybe someone can retrieve the pics for you but it won't help you solve your own problems if you're in need of quick help as you've stated. Good luck----7mmRHB

 

[Bravo 4]

No experience here but just a question/comment or two. Why shorten the cases instead of just necking the WSM case down? Send it back and have him run the reamer in to WSM specs. Why not make a cartridge by just necking up the WSSM case? Sounds easier, but as stated I have no experience with this.

 

[goodgrouper]

Here it is:

And a pic of the 7mmrhb next to the 300 ultra:

 

[WindTrax]

Thanks J E (-and Roy too!)

Ok, so I've talked to the gun smith who is both building the rifle and is making the dies. I just ordered 4 more 6.5mm die blanks and they are being shipped up to the smith (who lives near me) overnight for delivery tomorrow. We are getting together Saturday morning to both make the intermediate step dies plus anneal the cases. 2 questions:

1 - he just got in the Ken Light automated case annealer, but although it will give us the most consistent case neck and shoulder temps, he's concerned that with a case this short/fat, the automated rotary case annealer might allow too much transfer of heat down to the base. Anyone used an approach other than the water-in-the-pan method on pretty short fat cases and should we be concerned? Obviously with 200 - 300 cases to do, this will go MUCH faster - if it works ok...

2 - I've heard there are 2 possible designs we can go for on the form dies; the first is with the first die to severely reduce the existing shoulder angle while leaving the distance between the current base to the current neck/shoulder junction unchanged but moving the distance between the base and the body/shoulder junction to the target length of 1.298"; then with each successive die, start to re-steepen that shoulder angle, essentially making the neck longer and longer as we decrease the distance between the base and the shoulder/neck junction point. The second option is to instead leave the neck angle alone, and essentially with the first die move the body/shoulder junction back but only for to that 1.298" point by shoving it back, but only to a case diameter of about .06: to .08" with each pass, for 3 to 4 passes - so in other words, half way through the 4 passes with the first approach we would have a case with a very long, very gentle sloping shoulder, while with the other apporach, half way through the 4 passes we'd have a case with have a case that looks like it has 2 shoulders (until we completed all the passes of course.) Make sense?

So my question is, which of the 2 approaches is better - create a very, very shallow sloping shoulder and gradually steepen it, or push the shoulder back, keeping it 35 degrees, but take 4 passes to move back the entire shoulder? I've has one person each, both very reputable, recommend each method. So any input from anyone whose done this (ESPECIALLY with these doggone thick/apparently harder than average) WSM cases (I'm using Winschester cases in face) would be very appreciated. We only have 4 blank dies to do this with and are running very short on time, so it's critical we get it right the first time on this Saturday morning. Thanks everyone for your time!!!

 

[7mmRHB]

Thanks Grouper. The pic reminds me how much work is involved in making a case shorter !!! ----- 7mmRHB

 

[WindTrax]

No experience here but just a question/comment or two. Why shorten the cases instead of just necking the WSM case down? Send it back and have him run the reamer in to WSM specs. Why not make a cartridge by just necking up the WSSM case? Sounds easier, but as stated I have no experience with this.

Hi Bravo,

I have very specific goals in mind;

1) more case capacity than either the 6.5 WSSM or the .260 offer
2) must be able to function in a *short action* repeating bolt action using 140 and 142-grain class bullets, not seated below the cases neck/shoulder junction (thus reducing case capacity)
3) must have a bit less case capacity than the somewhat over-bore 6.5x284

The 6.5 WSM (not WSSM) is substantially greater capacity than the already slightly overbore 6.5x284, thus the reason I'm not going that route. Thanks for the thought though!!

 

[WindTrax]

Scott, I have done pretty much the same process that you are attempting but with a full 300 RUM case. You cannot move the shoulder back .300 with one form die, annealed or not!! My form die set has three form dies and a full length sizing die.The shoulder must be pushed back in stages from the outside so there is someplace for the brass to flow to. The third die gives you the new neck ( thats about 1/2" too long )which needs to be cut off and requires inside neck reaming at that point to get rid of the Donut at the neck shoulder junction. Now you anneal and full length size, trim to length and neck turn. The necks need to be turned because of all the added brass that flows in during the forming process. 300 WSM brass is already very thick in the neck before you even started the forming. About .018 to .020 I beleive.

GG once posted a pic of the steps in forming my 7mmrhb wildcat on LRH but I don't have the skills to go locate it. Maybe someone can retrieve the pics for you but it won't help you solve your own problems if you're in need of quick help as you've stated. Good luck----7mmRHB

Actually THANKS 7mmRHB and GoodGrouper! That is *precisely* what I was needing to know. So an outside push-back, multi-stage approach is the answer. Thanks a million. We have 4 blank dies that are supposed to arrive tomorrow and can machine up new dies (or rather the gunsmith can) and this will work stellar. I have the ablity to either neck turn or ream, and he just got the Ken Light Neck Annealer, so this just should work out perfect. Thanks again!