Generally plastic of this kind would be of bad quality would it not?
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damn. You had me all excited for a second xDbobgengeskahn said:ME as in Mechanical Engineering.
And this is my thinking for trying it, however the seal that is created in RS vs. the 'seal' (or lack of) that is created in airsoft may cause an unacceptable bleed of pressure. The other concern I have with a boat tail would be exposing the fins to the air flow from the cylinder (planning for a HPA set up) would cause the BB to rotate counter to the intended spin once it leaves the barrel. I may just be over emphasizing the effect in my head... all the more reason to test![]()
On a slightly more serious note, I have been looking all day and have yet to find a way to build an acceptable mold. I have mainly been looking into injection molding and some rapid prototyping techniques. Anyone have any ideas for an accurate cheap way to cast things?
Before you have a mold, don't you need something to mold with?
If possible, what about a CNC'd mold? Probably a one piece that would need the flashing sanded, or a totally CNC'd piece of ammo? Thought that would be expensive.....
There are a few ways to make molds depending on the manufacture process you're going to use. Most likely since this would be a "garage style" build I'll have to get one pellet built out of 7075 or some sort of steel and use that to cast off of... and it honestly wouldn't be that difficult as long as I can draw it in CAD first (I know some people that would be able to cut it, might take a while, but free is worth waiting
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Another possibility would be to go straight to the mold and design that on CAD and have it cut, but like I said, designing a 3 part mold is very difficult to get right, especially on a 6mm by 12mm round, or even if I go to a 8mm. (I am still looking for a 10mm/0.40" tube since that is where I'd like to end up, just cant find anything precise enough to be the barrel, so if anyone knows anywhere...)
Another possibility would be to go straight to the mold and design that on CAD and have it cut, but like I said, designing a 3 part mold is very difficult to get right, especially on a 6mm by 12mm round, or even if I go to a 8mm. (I am still looking for a 10mm/0.40" tube since that is where I'd like to end up, just cant find anything precise enough to be the barrel, so if anyone knows anywhere...)
Unfortunately with both of these ideas is that if I were to bore a stock barrel the wall would be too thin (stock barrel OD is usually only about 10.5mm) and I couldn't assure 10.0mm +/- 0.001 or even +/- 0.01 with a drill that long.
I have found some 10mm ID tube (tube is measured by OD, pipe is measured by ID for those that may not know the difference), however they only guarente accuracy down to +/- 0.05 usually or worse, which in airsoft barrel terms is HUGE as most of us know
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I have found some 10mm ID tube (tube is measured by OD, pipe is measured by ID for those that may not know the difference), however they only guarente accuracy down to +/- 0.05 usually or worse, which in airsoft barrel terms is HUGE as most of us know
If I can find a precision 7 or 8mm barrel I'll try to go with that, but the barrel hunt will have to wait till I can decide on an actual size for the BB.
I have spent most of the day looking at different casting techniques and started reesarching different .410 sabot/slug designs. There are both rifled and unrifled slugs for the .410 and it seems from the forums that I have read that the rifling on the slug does not actually spin the slug at all and is more for looks than anything else. What do you guys think? I have not heard anything else either way, however after thinking about it I could see it going either way. On the one had it would make sense that curved v. straight cuts would make a difference, on the other hand the control surfaces would have to be rather large to make a difference.
My original plan was to make rifled rounds and find a way to hook up a high speed video along the flight path to see if they actually did spin... but for ease of manufacture it would be nice if I could clear this up before custom building a rifled mold (because that would only be about 10x the cost and about 100x the headache of not rifling it
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I have spent most of the day looking at different casting techniques and started reesarching different .410 sabot/slug designs. There are both rifled and unrifled slugs for the .410 and it seems from the forums that I have read that the rifling on the slug does not actually spin the slug at all and is more for looks than anything else. What do you guys think? I have not heard anything else either way, however after thinking about it I could see it going either way. On the one had it would make sense that curved v. straight cuts would make a difference, on the other hand the control surfaces would have to be rather large to make a difference.
My original plan was to make rifled rounds and find a way to hook up a high speed video along the flight path to see if they actually did spin... but for ease of manufacture it would be nice if I could clear this up before custom building a rifled mold (because that would only be about 10x the cost and about 100x the headache of not rifling it
Why not buy a cheap as chips second hand .22 air rifle and hack the barrel off that? It will be pre-rifled for you!!
As far as making the ammunition is concerned I dont know how they make BBs so smooth and shiny, but I would avoid a rapid prototyping machine as the surface of the shapes they produce is very grainy, you would end up with dimpled BBs after all!!
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As far as making the ammunition is concerned I dont know how they make BBs so smooth and shiny, but I would avoid a rapid prototyping machine as the surface of the shapes they produce is very grainy, you would end up with dimpled BBs after all!!
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