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DistRifle
01-13-2014, 07:48 PM
I just got a 6-cav 7mm Soup Can mold from Midsouth. I cast up a few samples. They look good, until you put a mic on them. They measure almost .289. When I size them .285, the lube grooves are almost gone. Anyone else have this issue whit the Soup Can?

Alloy was indoor range lead which is a mix of Cast, Jacketed, and 22 + tin for fill out.
934799348093481

Thanks!
Harvey

PS. I know the top punch did not fit well. Anyone know which one fits?

Tatume
01-13-2014, 08:38 PM
Hi Harvey,

I think you're showing plenty of lube.

Take care, Tom

TCLouis
01-14-2014, 12:11 AM
Wasn't that version of the "Soupcan" boolit mold made up especially for loose 93-95 Mauser barrels.

My "Soupcan" boolit sizes slightly with .285" die and plunks them downrange pretty decently out of my Husky 7mm Mag.

Nice light fun gun with cast boolit.

dromia
01-14-2014, 05:41 AM
Shoot them and see how they do, the target always tells.

BABore
01-14-2014, 12:23 PM
Measure the inside case neck diameter of a once fired round from your gun. You can do it with calipers by gently applying outward pressure on the caliper jaws while rotating the case. Make sure the case doesn't have any mouth reduction from a prior crimp. Flare it slightly if there is one. The diameter you measure will be the largest diameter boolit you can safely fire in your gun. A new case will expand outward upon firing to seal against the chamber wall. It will springback approximately 0.001 or so when pressure drops. Your measured diameter will allow the boolit to release cleanly without pressure jacking up from a chamber/case/boolit interference fit. Your barrel will act as the final sizing die. You will get a slight start pressure increase due to the oversized boolit being sized down. The harder the alloy, the greater the spike. As long as you work up your load accordingly, there shouldn't be any problems.

DistRifle
01-14-2014, 06:58 PM
Thanks for the replies. I'll try a few. I usually have boolits casting small with this alloy. I was surprized to see them come out that large.

MtGun44
01-15-2014, 12:46 AM
I believe it was intended for 7x57 Mausers which frequently slug at .286 or .287 so .289 is perfect.

If you lube the grooves and THEN size it down, the grooves will not be reduced. The lube is trapped
and forces the grooves to remain open.

Bill

Teddy (punchie)
01-15-2014, 01:10 AM
Harvey

Top punch maybe a 20 RCBS looks close any way. I only have one or I would sell it. measures .259 OD at punch and is a RN, FT (round nose flat tip)

I'm getting a list of them together to sell extras If I come across any that look close I'll PM you. Better yet PM me in a week, if I don't get back to you. I get busy and side tracked forget things. Teddy

blixen
01-15-2014, 01:51 AM
Is midsouth's double cavity 7mm mold the same diameter as the 6-cavity?

leadman
01-15-2014, 02:02 AM
The photo seems to have a wide mold seam on the boolit. Is the mold closing properly? Check the pins and for lead or burrs on the faces of the mold.
I have a couple of these and they cast at .287".

leadhead
01-15-2014, 10:53 AM
If your not happy with it, I'll take it off your hands.
I have a few oversized 7mm military rifles that would
love this mold size. Let me know.
Denny

DistRifle
01-15-2014, 10:37 PM
I'll check the mold to see if it closes all the way. Maybe that's the issue. Leadhead, I'll let you know if I end up selling.

I was looking at a Lyman 346 top punch. It doesn't have the flat nose, but looks like it might work. I can always put some epoxy in it to create a good fit. I tried the RCBS 531. But the flat nose is smaller and the nose is narrower.

Thanks for the input.

DistRifle
01-16-2014, 12:44 PM
I checked out the mold last night. Looks like the alignment pins are holding it open. So, I tried to adjust with a punch and hammer - like I've always done. No dice. They wouldn't budge either way. I actually made it worse because the pin swaged out some.

I called Lee today. They said the pins are basically not adjustable any more because they got so many complaints about them falling out. But, they'll take it back and correct the issue. Back to Lee it goes. We'll see how it casts when I get it back.

leadman
01-16-2014, 04:45 PM
I looked at the spec on this mold and it is supposed to drop at .286". Hope yours does when it gets back.

45-70 Chevroner
01-16-2014, 05:48 PM
Lymans 4th. edition Cast bullet handbook has a Top Punch crossover chart for Lee, and Saco (Redding) cast bullets.