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TREERAT
05-30-2009, 03:11 PM
would you be interested in making me a paper patch mold? Please! if so how much money would you need?

longbow
05-30-2009, 04:00 PM
TREERAT:

If I had the time I wouldn't mind but I really don't.

I could draw one up for you though and you could take it to a machine shop to find out what they would charge. This is when friends with lathes are handy.

I modeled a pushout mould for a shotgun in 3D and could copy that then modify it for your use and cut a drawing pretty quickly if you want.

Longbow

TREERAT
05-30-2009, 04:15 PM
since you do not have the time, I will try to make on myself, based on your desinge. thanks!

303Guy
05-30-2009, 05:09 PM
I modeled a pushout mould for a shotgun in 3D and could copy that then modify it for your use and cut a drawing pretty quickly if you want.
longbow, would you be so kind to send me a copy of your shotgun mold, please? I have this brand new single shot that was going to get a 'silencer', sub-sonic loads and a scope for use on possum but that never happened. Now I would like to shoot cast solids from it.

longbow
05-30-2009, 11:39 PM
303guy:

Do you want a drawing in PDF, AutoCad or 3D .stp file?

Are you shooting rifled or smoothbore? I am assuming you are talking cast solids from a shotgun.

These moulds will also do hollow base for a Foster style.

Also, are you wanting bore size or size to suit a shotcup?

Let me know what you want so I can revise the model accordingly then give you watever file format suits your needs.

TREERAT

I can model and cut a drawing for you if you tell me what boolit shape you want. You have already given diameter but what about weight and nose?

Also for both of you. I have made moulds with a full diameter sliding nose form and also by reaming the cavity to shape the using a small ejector pin which can be shaped to suit the boolit nose, flat or hollow point.

The benefit of full diameter sliding nose form is adjustable boolit weight.

The benefit of a formed cavity and ejector pin is absolute concentrcity of the cavity.

A picture is worth a thousand words though so maybe I had better post a sectional view of a mould so you can see what I mean.

I'll try to have a couple of examples in a day or so then you can let me know what suits your needs.

Longbow

303Guy
05-31-2009, 12:49 AM
Thank you kindly, longbow. AutoCad 14 would would do me nicely, thank you. I am not sure what I want to do. It is a smooth bore, not sure what choke. I think I would like to shoot bore size or PP. I'm not sure what would give reasonable accuracy. Accuracy is what I would like if at all possible.

A friend of mine once made slugs for his 'silenced' single shot. He cut thick felt wads and screwed them on just like the Brenneke slugs. I still have some of those, mmmm..... this friend used a hex socket as a mold, then squeezed them in a vice to get the 'splines' to required diameter. They worked! At subsonic they were quiet too! I've no idea of accuracy.

longbow
05-31-2009, 01:44 AM
303guy:

If you have followed my posts, I have had many, many failures in the accuracy department with shotgun slugs!

So far from bought slugs AQ, Gualandi and Brenneke have done very well. Some factory Fosters have performed quite well but home made efforts have been hit and miss (hah, no pun intended).

So far the most reliable and predictable have been round balls in various types of loads. Not extraordinarily accurate but usually 4" +/- at 50 yards.

My Lyman Foster mould gives consistently terrible accuracy. I tried paper patching to bore diameter which helped but still got fliers

Some home made hollow base slugs have done as well as the round balls and some AQ or Brenneke clone have done very well but I still get fliers ~ I think due to small inconsistencies in the attached wad.

I have made quite a few AQ clones which have been fairly successful but again too many fliers for my liking. My feeling has been to cast a hollow base slug that flies well so it is repeatable. However, the only really good accuracy I have gotten from a Foster is the Rapine 730560 which has a very thin skirt.

I keep thinking that Brenneke got it right but home made Brennekes are time consuming to make and difficult to get everything consistent.

I made a jig so I could use hot melt glue as an attached skirt/wad as it is cheap and easy to get ~ and tough. I pour these in a one wrap paper tube so the paper bears on the bore. Hot melt would make a mess and I certainly don't have the money for injection moulding equipment. Got some pretty good results but also too many fliers.

After recovering some 0.735" round balls shot into deep snow I found several that had very uneven swaging so have to conclude that maintaining alignment as the slug leaves the hull and enters the forcing cone is critical. That may seem pretty obvious but it really surprised me that a round ball over hard card wads could get so unevenly swaged.

I think a slug with about 1 caliber bearing surface and attached wad (Brenneke style) should solve the alignment issue.

Another option if you have them available are steel shot wads with thick unslit shotcup. A slug of about 0.655" to 0.662" jammed in makes a slug much like the Gualandi DGS slug for smoothbore. The intention is that the slug and wad remain attached like a Hammerhead or DGS.

Anyway, I digress.

I will post a mould design for full bore hollow base 12 ga. And since it appears we have deviated from TREERAT's original question (sorry about that), I will also post a mould for his .358" for paper patch.

I guess I have to redeeem myself some for rambling so much!

Longbow

303Guy
05-31-2009, 02:12 AM
Thanks for that, longbow. Sorry 'bout that too, TREERAT.:drinks:

longbow
05-31-2009, 07:34 PM
TREERAT & 303guy:

Here are some views from the 3D models. You will have to excuse the colours. I do not have the expensive version of the 3D software so cannot make the photo quality images.

The reamed mould is one I made for a fellow that wanted a TC hollow point sold to fit a shotcup for rifled barrel.

The bored mould is one I made for a fellow who wanted a full bore TC hollow point.

I usually use 1 1/2" diameter round bar ~ normally just plain old colld rolled steel but the last couple I have made out of bronze round bar. The bronze is very nice to work with.

For the TC hollow base and finned slugs in the photo in my other post I used a shaped base plug and made a TC nose form of steel. I insert and remove the nose form with a magnet which works far better than I would have thought. I just did it because I was lazy and wanted to test the idea.

The finned slug mould is actually bored right through then I made a "plug" with the fin slots in it. The plug is a snug slide fit and held in place with a set screw. The mould was much easier to make so I think I will be boring through and using a separate plug from now on.

As mentioned, the benefit of the full diameter sliding nose form is that weight is adjustable. There is an appeal in being able to cast several different weight boolits from one mould.

Of course the rifle boolit moulds are smaller diameter but made in exactly the same way. I generally make a D reamer for the .30 cal moulds as they are a little hard to bore but .44 cal. and larger I usually bore.

TREERAT:

If you want me to make a drawing for you I can do that fairly quickly. I would model the mould in 3D then cut a 2D drawing with dimensions. You could then get a machine shop to give you a price on a mould. I have no idea what they would charge but if you limited their work to boring the cavity and making the nose form then the rest you could do yourself pretty easily.

I use 3/16" to 1/4" plate for sprue plate.

The handle is simply 1/4" threaded rod through piece of maple dowel.

Let me know and I will do what I can to help out.

Longbow

TREERAT
06-01-2009, 09:52 AM
longbow, I really like the looks of the last picture of the mold cut with hp ejector pin!
that is what I want!

if I want to drop a bullet at .351 diameter, and make a d-reamer what diameter should my reamer be, given that it will be used in a drill press not a mill, and still be able to lap and polish out all the imperfections caused by the drill?

stupid question, do you use the d-reamer to drill the cavity? or drill the hole for ejector pin then drill close to the diameter of nose almost to depth, then diameter of bullet almost to depth, then run the reamer in this pilot hole to cut to shape?

longbow
06-01-2009, 08:19 PM
How to answer... yes.

I have done all of the above:

~ drilled the ejector pin hole then bored
~ drilled the ejector pin hole then drilled larger but undersize for the cavity, then reamed
~ drilled the ejector pin hole then used the D reamer to "drill" the cavity
~ and lastly I used a D reamer with a pilot to form the cavity and center the hollow pointer all at once.

Simplest is probably to drill the ejector pin hole then "drill" the cavity with the D reamer. They aren't actually drills but so far I have found they work pretty well this way in both steel and bronze. Turn very slowly and slow feed with lots of WD40 or cutting oil!

You will have to make sure you have the mould face perpendicular to your drill press spindle within a thou or two or the boolit base will not be square to the body.

As mentioned, I turn my D reamer then mill or file in half ~ draw file and stone to finish. You will need a micrometer or good verniers to check 1/2 diameter or a thou under. Then harden and temper. Then stone to a polished finish. The edge should easily shave fingernail. If not it is not sharp enough.

Since they are 1/2 diameter they seem to warp (for me anyway) making them cut about 0.003" large plus you want to leave a 0.002" to 0.005" to lap depending on "drill" finish ~ better undersize than oversize.

So, 0.351" - .003" = 0.348" (for lapping) and 0.348" - 0.003" = 0.345" (for reamer warpage)

You might consider making the mould block out of aluminum or brass, both of which will work much easier than steel.

An alternative to the D reamer might be to buy the appropriate size drill bit (number, letter,or...) and very carefully grind it to shape (clearance angles will be the trick here although a truncated cone wouldn't be too bad) then drill about 1/64" undersize then very slowly and carefully drill with your shaped drill bit. You would ignore warpage here but the drill bit will likely cut a little oversize anyway.

I am not sure which is more difficult, hand filing a D reamer to diameter or grinding a tricky shape onto a drill bit.

Also, if you go hollow point, you need a very close slide fit of the ejector pin or the hollow point cavity will wander and be different in every boolit throwing balance off.

Actually, the last picture is not quite what I built. I decided to use a full diameter hollow point pin in a pocket then reduced diameter ejector pin. I did this so there was no chance for lead to get under the edge of the lip and cause the hollow pointer to stick in the boolit.

Longbow