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darrellsteenwyk-
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AlvinYork
What would you think of starting a thread in the Group Buy Discussion area for your 12ga slug? From what I’ve found, bore size for a 12 gauge should be 0.729 but I’m sure there’s a lot of variation out there. If you’re interested we’ll have to either move this thread to the Group Buy discussion group or start a thread over there.
Mike B.
You might possibly be better sticking with a .680 – .690 Diameter if you are going to shoot the slugs in a 12 Ga barrel that has insertable chokes to help protect the internal choke tube threads… if the choke tube is not installed…
Your call on that…That way one can still use a 12 Ga shot cup depending on your final slug cast weight… & still fit the slug into it nicely … Otherwise one may have to go really old school and use a fiber wad… If push comes to shove… a .690 round ball will also fit nicely into a 12 GA shot cup. In pure lead that is roughly an ounce and an eighth in circa (492 – 495 Gr) in pure Pb weight… Thus the basic reason for the NOE 680-500 slug mould offerings…
https://noebulletmolds.com/site/product-category/680/
The slugs can then be shot in a cylinder bore shotgun…, with or without the insertable choke tubes installed depending on the age of the shotgun shotgun and its barrel design. as the plastic shot cup tends to protect the bare choke threads…
If you decided to go with the larger diameter sans the shot cup… You will most probably at least need a wad & or a proper spacer of some sort in between the powder and the base of your cast lead slug…
It might not be the wisest of decisions to shoot slugs in a choked shotgun barrel… or a barrel with other than a cylinder choke installed…
Again your call on that subject…
It may tend to become a liability issue if someone was to recommend otherwise, & heaven forbid something happens… down the line… Remember you are talking about a 10 to 12,000 PSI firearm design, vs what a typical rifle or pistol cartridge is rated for…
Take Care & Stay Safe…
darrellsteenwyk
Attached is the SAMMI Spec for rifled shotgun slugs… along with the link to the SAAMI shotgun page…
You may want to check the 12 GA shotgun spec before you begin your rifled shotgun slug endeavor…
It may be that this will need to be a new mould design endeavor…
Your Call on that…
Take Care, & Stay Safe…
Thanks Mike B.!
We’d probably want a thousandth over, .730. I would say we’d want a few thousandths more and then we could size down to the size we want, to the size of your own barrel. But how would you size a shotgun slug?
Anyone have an idea for that?
Maybe an old shotgun barrel the size you want, sawn down to one inch pieces, then use an arbor press to push it through?Why would you want to size a shotgun slug if you can design the mould to cast it properly in pure lead with the diameter in the mould design set to .730?
If one absolutely had to one would have to design a die body based on the same 1 1/4 x 12 thread diameter that the 50 BMG uses for its sizing dies I.E. 1 1/4 X 12 THREAD SIZE, & then have a honing company do the inside to your 730 diameter diameter smooth enough so that you can push the cast lead slug through that .730 dia sizing die.
A whole lot of the newer cast bullet presses have their upper 7/8 thread section as a screw in adapter with the larger size thread being the aforementioned 1 1/4 x 12 thread size above… used in the actual casting.
Think of the NOE Die body but setup with the aforementioned 1 1/4 x 12 thread size to leave one sufficient wall thickness for a “.730 Dia.” honed hole for the sizing die
(Using the standard 7/8 die thread would make that die body wall end up being almost paper thin and most probably would not support the pressure needed to push your cast bullet slug through it…) even if it was only .001 or .002 over size.
I designed and had made something similar… though a bit smaller in diameter I.E. .575 for a 58 caliber BP Minnie design when the actual 58 caliber moulds were only made to throw .577 ++ dia. and the Minnie rifles barrel was cut so that it needed a .575 cast Minnie to drop freely down that barrel for that particular rifle…
You might also want to make the upper section of the 1 1/4 x 12 sizing die body design oversize by .100 or so…
So that once the slug is pushed through it would be free to be pushed up and out of that die body by the next shotgun slug… much as a case sizer, or a cast bullet sizer sans the lube feature design.
Then one would need to make a long push rod design that is basically about .001 smaller that is long enough… so that it roughly runs the full length of the die sizing die body honed diameter… when the press ram is at the top of its stroke…
That can basically the same as the type that is currently used for the NOE hand punch ram with the seating die adapter cut into its base… so that it can be snapped & locked into the normal press ram…
Tooling to do the job can be designed & can all be manufactured to do the work if one had to absolutely need that diameter @.730…
The question is if you are only going to cast said shotgun slug (Probably a HB version) with pure lead whose shrink rate is more of a certainty… is… Why would you want to…in the first place…???
Your Call on that…
It would I believe be a new mould design with the aforementioned tooling needed if one required a pure .730 diameter sized 12 GA bullet slug… for a shotgun that had been reworked to have a rifled barrel…
Your Call on that… potential new mould design as looking back through the NOE forum records I found nothing larger than a .680 cast bullet design having ever been offered by NOE…
Thus my initial comment on the NOE .680 mould offerings
However you may know more about that than I…
Take Care & Stay Safe…
Gentlemen
Attached you will find a quick design sketch of a .730 dia slug… drawing sketch for an ~ 500 Gr slug similar to the current NOE .680 design still being offered… only super sized to .730 as requested in this forum subject…I also attached my original initial draft for the 58 Minnie in case someone wanted to go that route to make a 1 1/4 x 12 threaded die… Thus the .570 would become a .730 and the .565 would become circa a .725 push rod… depending on how accurately one can turn the push rod vs the ability to have the rod ground to a specific diameter to sill provide a slip fit into the sizing die body…
Hopefully the initial draft concept dwg will help augment to flesh out what I stated in my last posting on this subject…
Take Care & Stay Safe…
Correct me if I’m wrong, but the “giant pellet” design is for a sabot. Lyman has both a 20 and a 12 mould in this style and they are called “20/12ga Sabot Slug Mould”. So I would say your second option there is probably a better starting place.
I fished around a bit looking for a good diameter and found this on Ballisticproducts.com
The ThugSlug in 12ga is sized to 0.731 and the Thunderbolt slug is .736.
The LBC BluForce is .740 but I would imagine that’s the diameter of it inside the sabot.
So 0.731 seems like a good diameter, I would think.
I also did a couple of the other versions of the slug design that you mentioned before I did the design that I posted. Those designs ended up having more width to get to an ounce and an eighth than length…
If you like I can post them… for you to look at… I set the software design to pure lead before I began this endeavor… I don’t believe that you want to go more than an ounce and an eighth in total projectile weight which is right about 495 grains, as an ounce of lead is basically 437.5 grains if one takes 7000 grains and divides by 16 ounces in the pound… You may note that the alloy used in the current NOE offerings at .680 are not actually pure lead… the alloy mix is closer to a very hard alloy than pure lead… that may or not have been fixed by increasing the size of the hollow base in those designs to bring the weight back down to the circa 500 grain concept…
Thus one would basically need to attach a thick wad to the back of the cast lead to give the resultant combination more length than width… for ballistic stability…
In my opinion it is not a very good ballistic design to just have a lead slug that has more width than length without the attached wad to complete the package..
It also tends to complicate the final assembly of said slugs in using a screw or some other type of more permanent fastening method to attach the wad to the lead slug… as one would need to fabricate a thick wad to attach to the lead slug by some more permanent mechanical means..
One might be better off with a .690 round ball… ballistically speaking… At least it fits nicely into the 12 GA shot cup of a 12 GA and I believe tended to made 12 Ga cartridge slug assembly a whole lot easier…
I think that if you take a second look at those .730 slug designs that you referenced then you may see what I mean…
Your call on that… If you want to see those two alternative designs I will post them… one can only go so big and still try to maintain an ounce and an eighth slug weight… to facilitate said slug design…
Your “Sabot” reference to the design is actually what the .680 NOE designs are… That allows them to fit nicely inside a shot cup for ease of reloading assembly… and still retain some ballistic design stability.
Thus the circa .730 dia design concept, with the larger Shuttle Cock or “Sabot Design” as you call it … for ease of casting, & thus would basically require only a thin wad between the slug and powder… In the .730 design concept you are talking about…
You may note that there is also going to be no shot cup involved as the larger diameter just tends to just fit inside a 12 GA case… case trying to put said slug into a plastic shot cup will I believe only tend to bulge the shotgun shell…
Also I tend to believe that you will find that the 12 GA case wall thickness between paper cases vs plastic cases needs to come into play in the final OD design picture… As paper and plastic cases tend to have different wall thicknesses.
Did the Slug offerings chart that you referenced also have illustrations of those slugs that went with the comparison chart…? I might tend to venture to guess that if they do… that there is a wad of some other material attached to the back of those lead slugs to act as its wad to separate the lead from the powder…
Yes one can design the more traditional versions of the slug… & be able to cast the same… It then becomes a potential assembly issue once that they are cast to find the right combination of wads to complete the assembly of said slug cartridges…
If you would rather not want my help ballistically speaking… I will step back on this subject for the moment, to let those with a different opinion express their thoughts…
If you want to see those other more traditional slug designs then please let me know…
Take Care, & Stay Safe…
Attached is an image of a 12 GA thug slug using the source listing that you attached originally in response to my original “Shuttle Cock” — “Sabot Design”…
As you can see the slug is designed to come with a wad in this case as a spacer that detaches from the slug in question…
My question to that other design concept is… Where is that other design slug caster going to get the mating part needed for said slug concept design to put together a finished product?Is there a source for just the mating plastic component that those casters can purchase in quantity…?
Here are those alternative designs that will basically need to have spacers manufactured or built up out of other materials…
If one can keep the larger diameter slug design long enough… then one can potentially use a shot cup with the petals cut off as the needed slug spacer… Thus the shuttle cock design in a .730 vs a .680 design diameter.
However make the slug too short , & that option basically goes out the window… as a simple spacer solution.
I am open to the ideas for making a spacer out the current design shot cups… knowing that for shotguns any formula needs to be much more precise than with rifle, & pistol mould designs due to the much lower max pressure restrictions placed on a shotgun barrel rifled or not…
Also recipes for shotgun loads basically need to be much more exact in components, otherwise the pressure build up can skyrocket with unpleasant consequences…
For the sake of convince I set the other slug designs up so that to change from a 1 Oz to a 1 1/8 Oz all one had to do was to change the HB insert… I figure that the end product might be more sale able if that were the case to allow one to be able to cast both common design weights…
It’s not the way that I would go to solve this problem but I will not be the one shooting those slugs… with potentially cobbled together spacers…
For the sake of convenience I also attached two excerpts referencing the Lyman source for slugs to help illustrate the production assembly design needs… for those alternatives to the existing shot cup formulas…
The additional reason that I used the shuttle cock design is that years ago I talked to Al about utilizing existing NOE tooling for the manufacture of similar designed though different diameter moulds…
Whether he sill is or not interested…. in that concept… I cannot say… as I have not heard back from Al for a good long while now…
Al at that time appeared to be very open to the concept… It might possibly potentially save one from the dreaded 10 new individuals, threshold… & potentially put one into the 5 person category… if existing .680 tooling can be utilized to produce .730 diameter product… with only the HB insert needing changing…
Your call on that… design concept path… Now you know basically why I chose the shuttle cock path… rather than the other slug path…
Take Care, & Stay Safe…
Attached is a possible path to potentially be able to use a standard 12 Ga plastic wad with the shot cup for the .690 dia slug version, & sans the shot cup petals for the .730 dia design…
I had to go with a truncated cone design to try to keep the original .770 OAL and still give one a large meplat on the front end…
I was able to just keep the .770 OAL length on the slug in both instances by making the insert for the two different ounce and one eighth slugs with two very large HB plugs…
I do not think that one will be able to do a 437.5 – 438 Gr. one ounce load as the HB plug needed would potentially be very large, & may tend to cool off in between casts… thus not produce good consistent product…
In order to do the lighter one ounce the OAL would need to be reduced from .770 and thus put one back into potential conundrum for easy to find commercial spacers for a .730 dia version…
As it is the current HB plugs for the ounce and one eighth are quite large… & thus may also potentially be problematic… cooling wise…
From designing HB base plugs for my Minnie balls the draft angle on the plug needs to be at least 7 degrees or one tends to get the plug to cool without releasing the cast projectile…
Also the HB plugs OAL tends to come into play cooling wise when casting
It is what it is…
Take Care, & Stay Safe…
https://noebulletmolds.com/site/shop/626/626-410-hp-ag5-1-cavity-pb/
so why not just take this mold and make it .730 dia?
ounce and a quarter or ounce and a half loads are not unheard of.
maybe add one more lube groove, and make the existing lube grooves a little deeper to shed a bit of wt.
do away with the ‘crimp’ groove.i shoot the full bore slug out of my 20 ga with the lube grooves full of lube, it works great!
AlvinYork
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