farcticox1 wrote: ↑

Wed Jan 06, 2021 5:19 pm

I guess an old rifled barrel would be the answer, but I think that's kind of cheating :?

Rifling buttons are cheap on aliexpress. Just saying, like.

How about using a reamer? in brass you could probably ream from 4.2 to 4.5 without steps, or pick up an adjustable reamer and use that.

jackssmirkingrevenge wrote: ↑

Fri Jan 01, 2021 6:25 am

I have to say that after being the bane of my machining existence for many years cutting threads is a real pleasure now!

Nice result!

Doesn't it? 🙂 No, it doesn't. It indicates an inability to correctly express oneself. Text is perfectly capable of conveying emotion and intent; there's a whole section of the arts dedicated to it. It's been around for a while, you might have heard of it. It's called "literature". You'll perhaps al...

PracticallySane wrote: ↑

Thu Dec 31, 2020 11:49 am

I will concede though, it doesn't seem like you are worried about the proper science, rather that your opinion is fact.

PracticallySane wrote: ↑

Thu Dec 31, 2020 11:51 am

I do want to reiterate though. I mean no disrespect.

Really. Because putting a smiley on the end makes it all so much more polite.

Happy new year.

To a certain extent, you'll always be pumping water in, unless you live somewhere with absolutely 0% humidity. You're also adding water vapour through combustion, as you note. After combustion, the pressure in your chamber goes to its maximum, and then reduces as the projectile (if any) is pushed do...

I dont think you actually Google the magnus effect? Its not the "aerodynamic" effect. It's absolutely aerodynamic, and I didn't need to google it. Higher education in physics will do that for you :) What would you suggest as a mechanism for the magnus effect other than aerodynamics? Unicorn farts, ...

I wasn't suggesting he should use a rifled barrel*, I thought that was fairly clear. What's important is imparting a known and consistent spin on the projectile such that the aerodynamic effects can be compensated for. A hop up does this by imparting backspin on the projectile, using the aerodynamic...

Is there anything different? Quite a lot, going through the list above :) I'm no expert on bbs, but something with a smoothbore barrel and no other "gizmo" to ensure reliable, repeatable spin of the bb is going to result in random or more-or-less random spin, and thus bbs wandering off anywhere the...

Welds are a risk. Firstly, the weld itself is an unknown quantity. Next is the alloying of the base material(s) and any filler used, which leaves another unknown. Hydrogen absorption into the weld puddle is another risk. Without subsequent heat treatments (for which the welds themselves pretty much ...

There's also the question of how it's capped, etc etc. Pressure vessels aren't, perhaps, rocket surgery, but there's still a lot of hard theory involved, and major consequences if you get it wrong. The only way to be sure, without putting yourself in danger, is hydrostatic testing. Fill it *complete...

Yay! Nice results. Threading is hard to get right. Is the threaded piece in the foreground 2 pieces stacked on one another, or is it camera distortion that makes it look - ummm - "bent"? Meanwhile, and polluting your thread a bit (sorry) but it's a workshop thing, my surface plate is getting there. ...

Do you have a threading dial on your carriage? They save an awful lot of pissing about - without one, you need to stop the machine, reverse back to your starting position, feed in a bit, rerun your thread, lather rinse repeat until done, all without disengaging the carriage feed. This puts extra str...

Neat. Yeah, hand-cranking is the safest way to go, but it's properly slow. The next one is to thread away from the chuck, for normal threads that means mounting the tool upside down and running the spindle backwards.