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Mal Paso
11-21-2013, 01:05 PM
This is one of my first MP molds. Some time ago, before I realized it I had warn the outside edge of the mold so the sprue plate would not sit flat with the standard spring washer. I used it to test a patina with good results but had flanges on the boolit bases. Too good a mold to stop there.

The detent body is a 7/32" long piece of 5/8 bolt with a 1/8 hole for the ball and a "B" drill for the bolt. The ball is Brownells part #080-679-125, the spring #080-820-125. The bolt is 6mmx25mm with a split lock washer. The holes need to be far enough apart to clear the pivot bushing. I used a Bosch jigsaw and a HF drillpress to get that authentic bubba look.

The ball is right where the white dot is. The assembly seems to resist loosening better than stock and I have not used the set screw. I've only run 1 pot, have to mix more alloy and continue testing but it works well.
MtGun44
11-21-2013, 02:36 PM
Interesting idea.

Keep up the reports as you gather experience.

Bill
runfiverun
11-21-2013, 04:04 PM
is there a detent in the sprue plate for the ball to click into when opened and closed?
that would be pretty handy for some of the free swinging plates I have [where it would click open and click closed]
Mal Paso
11-21-2013, 08:56 PM
is there a detent in the sprue plate for the ball to click into when opened and closed?
that would be pretty handy for some of the free swinging plates I have [where it would click open and click closed]

No, but that's a great idea!

I was just trying to put the tension in the right place and keep it off the back side so it doesn't wear the brass.
paul h
11-21-2013, 10:02 PM
To make the detent useful you'd have to be able to lock the position of the collar that has the spring in it. I suppose that would be easy enough by tapping the collar for a set screw and having it bear against the pivot bolt.

Seems like alot of effort for something that a wave washer ought to handle fine, but I must be missing something?
Mal Paso
11-21-2013, 10:34 PM
The collar is "locked". MP molds have a sleeve around the pivot bolt and the detent body is sitting on it. They are both clamped between bolt head and mold block.

I should mention it took 10s of thousands of boolits to wear the mold corner although with this mod it would not have happened.