The Workshops

[8BitCosmonaut]

Hey Horus. Been a few days since I've worked on the automatic mechanism out of sewing machine parts. Here's what I came up with. Pardon my funny descriptions for I am not familiar with the professional Oxford firearm vocabulary.

About the bolt... I plan to use a "cam & follower lock delay" design, same as the USAS-12 because it's (hopefully) theoretically easier to machine than a rotating bolt. Which also requires it to be gas-operated, which is what I am most inconfident of.

EDIT: When it converts from full auto to pump action, there will be a mechanism attached to the fire selector that will transfer cycling authority to the pump handle, and blocks the gas tube. Changing back to full auto just reverses the procedure.

 

[Horus Lupercal]

When you say full auto, do you mean actual fully burst capable automatic fire or single shot semi-auto? Gas operation will be tricky as you'll have to work out much pressure you're gonna need to cycle the system properly.
Too much and it'll shake itself to bits, too little and it won't overcome the bolt lock resistance and spring force and won't cycle the weapon at all.

Cam and follower sounds easier to make, a rotating bolt and matching breech face with the required cams inside the bolt (like on an AR) may be a turd to machine.

 

[8BitCosmonaut]

When you say full auto, do you mean actual fully burst capable automatic fire or single shot semi-auto?

Like POM POM POM POM POM POM until the mag is empty or the trigger is released.

Gas operation will be tricky as you'll have to work out much pressure you're gonna need to cycle the system properly.

Yeah this is why I'm not confident of that.. Can't I just use the dimensions of an already working design? Like a Saiga or the USAS-12? I could make it recoil operated instead, like the Browning Auto 5.

I dont intend on trying out a blow back method, last thing I want is the bolt flying back too early and shoot hot gunpowder into the user's face.

Cam and follower sounds easier to make, a rotating bolt and matching breech face with the required cams inside the bolt (like on an AR) may be a turd to machine.

yay my intuition is correct!

 

[8BitCosmonaut]

Btw I have funny pranks you can pull on your friends or subordinates at the range. Fun for you and your friends.

1) weld the charging handle to the bolt on an M4 so everytime the guy shoots, the handle flies back and punches his teeth out

2) replace the 12 gauge shell in the guy's shotgun chamber with a .50 BMG round, place it back when he's not looking.

3) (stolen idea) replace some guy's 556 rifle magazine with 300 blackout.

4) replace a guy's makarov mag with 9x19 para rounds instead of 9x18

5) convince the left handed guy that the L85 is fully ambidextrous

 

[Chara-cter]

Horus Lupercal Do you think a double open sight like this would be practical irl?

thank you Mar very cool

 

[Horus Lupercal]

Do you think a double open sight like this would be practical irl?

Errrrmmmm yes ish and no. Depending on how you're gonna use them.

There's no defined 'centre' of the foresight, so you're always guessing where the actual point of aim is. That's not a huge issue in CQB if you just want to nail someone anywhere and they're basically filling the sight with bodymass to shoot, but if you're going for accurate shot placement (in the 'T' of the face for example) at anything over 25metres is going to be a matter of guesswork and judgement over precision.

The way I'd look at it is imagine having a scope/reflex sight system with a pointer, reticle etc and removing the pointer/reticle and then trying to use it. From experience trying to use Shield CQB sights with dead batteries, turned off EOTECHs or the dogshit 40mmUGL Fire Control Systems the army uses (which never work), you're not gonna do much more than make loud noises.

 

[8BitCosmonaut]

My new pillows have arrived.

 

[Pink]

Such pink.

 

[8BitCosmonaut]

Such pink.

The girly ones are always the softest ( ͡° ͜ʖ ͡°)

 

[Earl]

Not much, but I'm making some little rocket engines. First I made some black powder.

Then put it in an engine.

The thrust peaked at 20 grams. Needs some work, but it's working well.
Also, the engine you see is smaller than what I'm going to do later.

 

[TtTOtW]

Not much, but I'm making some little rocket engines. First I made some black powder.
View attachment 42874
Then put it in an engine.
View attachment 42875
The thrust peaked at 20 grams. Needs some work, but it's working well.
Also, the engine you see is smaller than what I'm going to do later.

Oh cool!

 

[Chara-cter]

How should I melt plastic? Some parts I need are too weak when made out of paper

 

[Earl]

How should I melt plastic? Some parts I need are too weak when made out of paper

Put it in a metal bowl and microwave it

 

[Altaïr]

Put it in a metal bowl and microwave it

If you do this there's a risk you melt the microwave too

No seriously, don't do this, never put metal in a microwave. I prefer to say it explicitely because I already heard about people that took such a joke in serious and destroyed their microwave (and nearly injured themselves)

 

[Horus Lupercal]

People, don't listen to Altair. Microwaves are magic boxes and can do wonderous things like charge phones and straighten out crumpled aluminium foil.

Other useful life hacks include cleaning and sterilising cutlery of any COVID 19 traces, drying small pets (much better than using the tumbledrier) and warming up tea/coffee inside a flask.

 

[Altaïr]

People, don't listen to Altair. Microwaves are magic boxes and can do wonderous things like charge phones and straighten out crumpled aluminium foil.

Other useful life hacks include cleaning and sterilising cutlery of any COVID 19 traces, drying small pets (much better than using the tumbledrier) and warming up tea/coffee inside a flask.

Nooooo
Don't say that, it happens that some Discord users read the forum, there could be an accident!
However I've heard that microwaving your phone while running SFS allowed to refuel your ship...

 

[Horus Lupercal]

However I've heard that microwaving your phone while running SFS allowed to refuel your ship...

True story. And it provides a buff to your ion engines (after all, you are providing more power to them)

 

[TtTOtW]

People, don't listen to Altair. Microwaves are magic boxes and can do wonderous things like charge phones and straighten out crumpled aluminium foil.

Other useful life hacks include cleaning and sterilising cutlery of any COVID 19 traces and drying small pets (much better than using the tumbledrier).

It's true, I microwaved my cat once. He seemed uncomfortable for a couple of seconds. Soon he proved to settle in quite nicely though. Say... He never woke up from his nap. Wonder why?

 

[Horus Lupercal]

He never woke up from his nap. Wonder why?

 

[Chara-cter]

plz tell me I did it wrong.........
I wanted the BB to fly at 25m/s. The bolt would only move 1.5cm in the receiver that means it will travel in 0.0006 seconds

The BBs weights about 30g

1250N or 127.47kg in 0.0006 second

Do I really have to apply over 100kg of force onto the BB?
Plzzzzzzz tell me I'm wrong ●~●

 

[Altaïr]

plz tell me I did it wrong.........
I wanted the BB to fly at 25m/s. The bolt would only move 1.5cm in the receiver that means it will travel in 0.0006 seconds
View attachment 43297
The BBs weights about 30g
View attachment 43299
1250N or 127.47kg in 0.0006 second
View attachment 43300
Do I really have to apply over 100kg of force onto the BB?
Plzzzzzzz tell me I'm wrong ●~●

If you want your bolt to go from 0 to 25 m/s over 1.5 cm, it needs a huge acceleration indeed. But the value I found is half of yours: 20833 m/s2. The time is doubled too: 0.0012 seconds. However that doesn't change drastically your problem, if you want to accelerate the bolt mechanically that requires basically a shock.

 

[Chara-cter]

A fancy drawing that actually makes people build what you draw
Wow

 

[Chara-cter]

So I did some research and...

Airsoft pellets are spherical projectiles used by airsoft guns. Typically made of plastic,[1] they usually measure around 6 mm (0.24 in) in diameter (though selective models use 8 mm),[1] and weigh 0.12–0.40 g (1.9–6.2 gr), with the most common weights being 0.12 g and 0.20 g, while 0.25 g, 0.28 g, 0.30 g and 0.40 g pellets are also commonplace.[1]

They only weight around 0.2g. That's.... way less than what the website told me >:T
Anyway, since those BBs are that light, I only need around 800g of force to launch it to 25m/s
Nice

 

[Chara-cter]

How do you calculate drag?

 

[Horus Lupercal]

How do you calculate drag?

You'll need to find the drag co-efficient of your projectile as well