Brennecke slug mold

[Chicken Thief]

Sorry

[longbow]

Looking pretty good!

I think you might need more and wider ribs though. I did in any case. Shooting will tell the tale.

I am surprised that Brenneke factory round is soft lead. Any I have handled are hard like zinc. It has been a while though ~ like 30 years.

Now we have two Brenneke tests to wait for! I am looking forward to results. Not to neglect your swaged slug (nice work by the way and quick!) but I am really interested in Cap'n Morgan's cast slugs since I am not a swager and have made a similar mould.

Waiting anxiously!

Longbow

[Cap'n Morgan]

Waiting anxiously!

I'm on it!

[MtGun44]

Both of you are amazing craftsmen!

Awesome work.

Is it true that Breneke slugs are no longer available in the US?

Bill

[Cap'n Morgan]

The mold is finished, and I did a small test today. A few notes:

The basic idea behind the design works as intended. When twisting the "lid" you can barely feel the inlets snap. Both the sprue and slug drops from their cavities without problems although it's important to let the slug cool a few seconds before knocking the center-plunger, otherwise the plunger will cause an indention in the the still soft lead.

The inlets are too small. Even with a quite hot mold the slugs had wrinkles and round edges. I'll try open them up from 2 to 2.5mm. Perhaps double their number from three to six. Also, the surface show some pockmarks, probably oil inclusions from the mold not being cleaned properly.

A pair of gloves - or at least one glove is necessary. The short handle of the top part gets HOT!

The weight of the slugs is 460 grains. Since the left-over alloy in the pot I used for testing had a very high tin content, and the slugs are not fully formed I think the final weight will be close to the 1-1/8 ounce (492 grains - or 32 grams) I was aiming for.

[Michael J. Spangler]

bravo!

awesome work.

now you need a video to go along with the pictures

[longbow]

Looking very nice!

Have you decided on what to use for attached wad yet? I think that will be the tricky part, getting an attached wad that will take the abuse of firing and still retain its integrity and shape.

That is one impressive mould you made I must say! Nice work.

Longbow

[oldpara]

MK II is up.

I added cavity for the bottom rim and hole for the screw.








Goes to show that it is possible but not easy to get a good boolit.

I will do some shots for this sundat and report back regarding accuracy

That is excellent work !
Good lookin slug.
Amazing what you can do when you love it

[Cap'n Morgan]

The mold is almost there. Once the inlets were opened a bit the filling improved - only a few traces of air inclusions in the ribs remains, but it's mostly a cosmetic problem. Probably adding vent lines between top- and bottom part will take care of it.

The center plunger will have to be a little longer to push the slug fully out of the cavity. I deliberately made it short enough that the whole mold assembly would fit under a Lee bottom dripper, but if I'm not careful the plunger will be pushed partly into the cavity during filling - creating a hollow point! Think I'll just add an extension or make a cut-out in the pots base plate.

[nekshot]

This is great watching talent unfold! I have been really getting bored with the rifles, so I think I hear the shotguns calling.

[longbow]

Well, nekshot, if you want a challenge a smoothbore shotgun should give you one!

Decent accuracy to 50 yards seems pretty easy but holding it to 100 yards, not so much... for me anyway.

I will be very interested in development of both Cap'n Morgan's and Chicken Thief's Brennekes.

This should be fun!

Longbow

[MtGun44]

Fine looking mold and superb results, sir.

Thanks for sharing.

Looking forward to the reports of shooting results.

Bill

[Chicken Thief]

Well, nekshot, if you want a challenge a smoothbore shotgun should give you one!

Decent accuracy to 50 yards seems pretty easy but holding it to 100 yards, not so much... for me anyway.

I will be very interested in development of both Cap'n Morgan's and Chicken Thief's Brennekes.

This should be fun!

Longbow

Shot with a Brown Bess for years i konw what you mean!
A roundball will shoot fairly true (under 4") at 55yds. The the devil saddles up and reaks havoc. In short the boolit start to rotate slowly in a direction dictated by the sprue and other imperfections. And as distance builds up it will deviate in that direction (badly!).
My Bess would go from @3-4" at 55yds to 12-14" at 80yds.
To deter the rotation some sort of "shaft" that will add drag and thus hold the boolit from spinning is mandatory.
And here we are, aint it fun

[longbow]

Chicken Thief:

I have been playing with Brenneke style slugs for some time now and still haven't got it right! Old Wilhelm was smarter than I am!

I still maintain that the main problem for the home crafter is consistency of the base wad. Small errors/deviations make a BIG difference!

But having said that, it is fun trying different things and now with you and Cap'n Morgan working on Brennekes I am optimistic that we will see some good successes!

Longbow

[Cap'n Morgan]

Added six .002 vent lines to the parting surface of the mold and did another casting session. I pre-heated the mold and didn't have a single reject. The slugs are a tad larger in diameter than I calculated (.732), it seems the slugs hardly shrink at all, only a little lengthwise. I recon it's because of the inner core preventing the slug from "caving in" during solidifying - No problem though, if necessary the slugs can be sized later. Now it's time to start thinking about the skirt and dust off the old MEC 600.

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[Michael J. Spangler]

WOW

awesome

[jmort]

You the man. Slugs are beautiful things and you have gone above and beyond.

[longbow]

WOW! is an understatement!!! Those look great.

Now the trick is get a good wad column/skirt attached and go shoot some!

Can't recall if you mentioned it but are these cast of soft lead or hard alloy? I am thinking hard alloy is the best choice and maybe water drop or even oven heat treat. So far most any hollow slug I have made needed a hard alloy and heat treating or they upset in the bore. These were pushed by fairly heavy loads of Blue Dot.

Personally I wouldn't worry about the 0.732" diameter as the ribs should easily swage to suit and give good fit to barrel. I have shot quite a few 0.735" balls cast of ACWW with no problems.

Looking forward to test results!

Longbow

[Cap'n Morgan]

Longbow.

Based in your experience I decided to machine some wads from solid plastic. My hope is to eliminate as many variables as possible in this first run. If the machined wads works as intended I have a yardstick to measure future wad material against. The wads will be 0.005 over bore size to help align the slug and prevent any wobbling down the barrel. I'm not sure the wad will seal properly until it's into the bore, so I'll add a base seal, cut from a used target load wad of which I have a never ending supply from the local clay target range.

I have no idea what precision to expect from this project. Since the slugs are mostly meant to be used by my Czech friends on driven wild boar, a 4" group at 50 yards will be more than satisfactory. I keep fingers and toes crossed...

As this thread is no longer mold related, I'll post any updates in the "Loading home made slugs" thread in the shot gun forum:

http://castboolits.gunloads.com/show...homemade-slugs

[longbow]

Cap'n Morgan:

I think a solid plastic wad is a good idea. I am too lazy to put that much effort into each slug though.

Another issue may be the gas seals. I do agree that you need one. I think even if the plastic wad is 0.005" over it will leak without a gas seal. I just tried some hard card wad columns using nitro card overpowder wads and they leaked so bad that the gas shredded some of the shotcup petals (I used cut off shotcups as "sabots").

Anyway, gas seals ~ try to recover some slugs especially if accuracy is not good. I have found that several types of gas seals have a tendency to fail at the edge of the seal blowing small chunks out and leaving a shredded edge. You need a good tough gas seal!

You might actually be better off to keep the gas seal separate under the slug so it drops away at the muzzle. Also, it may have a tendency to leak past the screw ~ mine did anyway. Even a stiff plastic wad will compress some. With a countersunk head screw you will have a nice flat base on the slug for a gas seal to press up against if you leave it separate under the slug, then not shredded edges to affect slug flight either.

Sorry to ramble on about what hasn't worked for me but if there has been a mistake to make or a way that doesn't work I have done it/tried it!

Anyway, these are looking very nice. I will be looking for range reports in the other thread!

Again, very nice job on that mould and nice looking slugs!

Longbow