7mm-300WSM wildcat
- Thread starter nheninge
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Well I necked down as we discussed and I got quite a few good cases (< 2-3 thou case runout), and some with VERY increased case runout (10-12 thou even). The best I can see is that the redding comp S type neck sizer does not give quite enough case support on new brass and allows the cartridge to move around in the sleeve loosely. Redding comfirmed this possibility with a phone call. The increased runout started when sizing to 0.333 to 0.329. Using a Forster press with floating die.
My questions are: MBrown, do you notice this effect?
Are there any other dies that might give a little better case support with new brass? Any experience with Wilson dies for necking down new brass?
Fire forming should straighten these up followed by FL resizing, but it would be nice to get them all as close as possible first.
My questions are: MBrown, do you notice this effect?
Are there any other dies that might give a little better case support with new brass? Any experience with Wilson dies for necking down new brass?
Fire forming should straighten these up followed by FL resizing, but it would be nice to get them all as close as possible first.
I just used a Redding Neck Bushing style neck sizing die to drop a 300 RUM case neck to 7mm RUM in a one neck bushing step last night. Before doing so, I started/coned the 300 RUM case neck down to less than .311 with a 25 RUM full length resizing die so that the case neck was able to enter the .311" diameter Redding neck bushing. After that, no problems using the neck bushing to take the 300 RUM case neck down to the 7mm RUM case neck diameter with the single .311" Redding neck bushing.
Other than using a conventional full length sizing die, as I suggested in an earlier post, I don't believe you should expect to get minimal case neck runouts using multiple Redding neck bushings until after you've fireformed your sized down cases in the chamber of your rifle.
But if you use a full length resizing die, then as long as the die is quality & concentric, the wildcatted case should be pretty uniform as it comes out of the full-length resizing die.
I anneal my case necks and shoulders after working them to the extent of sizing down a full caliber.
Other than using a conventional full length sizing die, as I suggested in an earlier post, I don't believe you should expect to get minimal case neck runouts using multiple Redding neck bushings until after you've fireformed your sized down cases in the chamber of your rifle.
But if you use a full length resizing die, then as long as the die is quality & concentric, the wildcatted case should be pretty uniform as it comes out of the full-length resizing die.
I anneal my case necks and shoulders after working them to the extent of sizing down a full caliber.
I knew fire firming and annealing was in the works. I guess I just didn't expect the spread of runout 0.000 - 0.0012. I kind of expected they would have all had similar (i.e. 7 thou) runout. Having a spread of this kind tells me that there is some inconsistency with the die setup and I think I can narrow it down to the loose fitting sleeve within the redding neck die. Sizing down was easy. Overall, I am very pleased with the ammo. Just a few changes to make the steps more efficient. Thanks again
My experience has been the more the case neck is worked down the greater the neck runouts. Especially with new brass that isn't held tightly in the reloading dies, because the virgin brass is purposely on the smallish size and allows for some additional slop in the dies. I expect you'll be in good shape after the initial fire-forming. I would anneal before I fired the brass in the chamber the first time. At least that's what I do. I like to soften up the work-hardened brass before slamming it out against the chamber walls. I've had some fire-formed brass split when the shoulders were blown out or forward to wildcat cases in the past. Never had a problem if I annealed the expanding portion of the brass first though. Good luck with your project. It sounds like a good one.
mo
Well-Known Member
So if you had a regular 7MM WSM could you neck down 300 WSM Norma brass and fire form them or do you have to have a rifle chambered for the 7mm-300?
srhaggerty
Well-Known Member
You have to have a chamber specific to the 7-300. 308nate told me they did this so that you couldn't load 270WSM into the 7WSM guns. Kind of like a keying effect.
This brings me to another thought. As I had 308nate build me a rifle that should be here today I hope. He chambered it in 7mm-300 WSM. He told me to get 270 brass as you only have .007 difference. So my question is why buy 4 bushings when one will do? What is the advantage of 300 versus 270?
This brings me to another thought. As I had 308nate build me a rifle that should be here today I hope. He chambered it in 7mm-300 WSM. He told me to get 270 brass as you only have .007 difference. So my question is why buy 4 bushings when one will do? What is the advantage of 300 versus 270?
geargrinder
Well-Known Member
I'm not sure I agree.
I ran a piece of 300WSM through my 7mmWSM FL die just to see what it would look like. The 300WSM is on the left, regular 7mmWSM on the right.
It would be a very mild fireform to make 7mmWSM out of 270/300WSM Norma brass.
bwaites
Well-Known Member
I'm not sure I agree.
I ran a piece of 300WSM through my 7mmWSM FL die just to see what it would look like. The 300WSM is on the left, regular 7mmWSM on the right.
It would be a very mild fireform to make 7mmWSM out of 270/300WSM Norma brass.
I was thinking the same thing. I was considering getting 50 pieces of Norma .300 WSM brass just to give it a whirl.
I think if you want to keep the longer neck, which is one of the reasons for the wildcat, that you should have the appropriate chamber, but if you simply want to use Norma brass, (supposedly better brass than Winchester), you could.
Have you shot any that you have done yet?
Bill
geargrinder
Well-Known Member
No I haven't. It just came across my mind yesterday when I was loading for the 7mm. Then I remembered this thread. So I threw a Win 300wsm in to see what it would do. I also asked this same question a while back and got some mixed answers.
I'm thinking of getting some Norma 270wsm and expanding to 7mm instead of coming down from 300wsm.
I'm thinking of getting some Norma 270wsm and expanding to 7mm instead of coming down from 300wsm.
bwaites
Well-Known Member
Run 5 through and go shoot them!
I'd love to see the results and so would lots of others. With Norma's supposed superiority it would be helpful to know if either would work.
Bill
geargrinder
Well-Known Member
Will do, but I have to break the barrel in first. Either me, or the family has been sick or the weather has been too bad to shoot.
I'll try some of the Win 300wsm's just for giggles.
I'll try some of the Win 300wsm's just for giggles.
bwaites
Well-Known Member
Awesome! If it works I'll buy Norma brass next go around! I've wanted to try it, but didn't want to spend the money since no one I have close by shoots .300 WSM to use it if it didn't work!
Bill
