Makeing a double paper patch mould

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homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Makeing a double paper patch mould

Post by homebrew .357 »

Hi All, I know I posted making a round ball mould and I have made a double cavity mould for my Sharps for 420gr lube bullets but no pics, so when I decided to make a paper patch mould for it I grabbed the camera. The first cartridges for the Sharps had PP bullets in them and I thought they would help polish the barrel. I make my moulds from ali, as I have a good supply, so working out the size required for a double mould I cut out two ali blocks, clamped together in the fore jaw chuck all fore sides are trued up square . Then one face on each block is machined flat and true, this is the inside of the mould . Pic`s so far. :D , Homebrew.357.
Attachments
Rough cut two blocks.
Rough cut two blocks.
The set up.
The set up.
Trueing up sides.
Trueing up sides.
All done.
All done.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

OK, now the face is true and flat I fit the line up pins before drilling the bullet cavity's, if you do it the other way it will not line up. I used three pins that I had in my comeinhandy box, three holes in one block for a tight press fit and sliding fit in the other one. Once the pins are in you may have to recut the sides true again , then I use a spruce cutter from another mould to line up the cavity holes and screw hole. Now it`s ready to setup in the chuck to drill the first cavity hole, centre first then a small drill goes in the full length of your bullet and slowly drill in to the ogive only with larger drills to just under the bullet size and then I use a D bit to finish. Homebrew.357.
Attachments
Cleaning up the face,x2.
Cleaning up the face,x2.
All done.
All done.
Pins in place.
Pins in place.
Lining up the cavities.
Lining up the cavities.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

The "D" bit was made from silver steel , lathed to size and bullet nose formed, then ground to half for the length of the bullet. The left side will be the cutting side, so all the rest is relieved buy grinding so it will cut on that side. Pre drilling out most of the hole makes it easier for the "D" bit to do its job, but you go in a few times to take out the spring. Homebrew.357.
Attachments
Centring up for first hole.
Centring up for first hole.
Hole ready for "D" bit.
Hole ready for "D" bit.
The 'D' bit doing it`s job.
The 'D' bit doing it`s job.
Reset for no two hole.
Reset for no two hole.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

Hi guys, Doing the second cavity is the same as the first one, with carefully in drilling you end up with a nice formed pp bullet mould. 8) Homebrew.357.
Attachments
First in with small drill.
First in with small drill.
Larger ones, then "D" bit.
Larger ones, then "D" bit.
And this is what you get.
And this is what you get.
The double mould and "D" bit.
The double mould and "D" bit.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

Hi, As you can see this is for guys who have only a lathe and a few bits to work with in there work shop, you guys with all the bells and whistles it`s easy as. I use the handles and spruce cutter off one of my Lee moulds, so the next job is to mill the slots on the side of the blocks for them. Once that is done the pin holes for the handles are drilled, two pins are made up and are retained in place buy two screws. Fit the spruce cutter and you are good to go. :wink: , Cheers, Homebrew.357.
Attachments
Slot milling.
Slot milling.
For the handles.
For the handles.
Drilling side pin holes.
Drilling side pin holes.
Two screws to holed in pins.
Two screws to holed in pins.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

So with mould finished I had to find out how it would cast and what weight of bullet, set up the lead pot and candle smoked the moulds . I got one bullet at 406grs and one at 420grs, one mould is slightly a bit deeper, my rubber Vernier gauge. Now to have fun learning all about pp patching bullets, that's all folks , Cheers, Homebrew.357.
Attachments
All came out good.
All came out good.
Two different sizes.
Two different sizes.
Its all under way.
Its all under way.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

So how did there go, well not to bad at 100m, a few mistakes on my part, I had refixed the front sight on as after my last range session I found it was to lose in the dove tail and so had to reset the sights with the first five shots. Now with this going on I forgot to clean the bore between shots, :roll: , finally got it sorted, aiming at 6 o'clock the first shot was low, upped the back sight and it`s getting there. I think it likes the pp bullets with 65grs ffg so will keep at it as this will help polish the bore. Cheers ,Homebrew.357.
Attachments
First five left, resight, clean the bore and not to bad.
First five left, resight, clean the bore and not to bad.
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steamin10
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Re: Makeing a double paper patch mould

Post by steamin10 »

Maybe I did not catch it, but what was the procedure for 'Polishing' your barrel?

I was instructed to use a stainless brush on a drill mandrel, using 30- 50 strokes to brush the lands of roughness, and then stroke the bore with a patch and fine grind compound 50 to 100 passes, with visual inspections every 10 passes or so..

Good, or just BS?
Big Dave, former Millwright, Electrician, Environmental conditioning, and back yard Fixxit guy. Now retired, persuing boats, trains, and broken relics.
We have enough youth, how about a fountain of Smart. My computer beat me at chess, but not kickboxing
It is not getting caught in the rain, its learning to dance in it. People saying good morning, should have to prove it.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

Hi Steaming 10, for the Sharps barrel I lapped it with a bore cast lead lap, 600grt first then 1.200grt past. I make up the lapping past by burning a bit of emery paper, you just have the grit left, mix with a bit of oil it`s good to go. And using p/p bullets helps polish it as well, so a few 100 more bullets down the barrel should see it right, Cheers, Homebrew.357.
Last edited by homebrew .357 on Thu Jul 21, 2016 4:56 pm, edited 1 time in total.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Makeing a double paper patch mould

Post by homebrew .357 »

And for my next project!!!!!!!. Well maybe, Homebrew.357.
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