Search found 30 matches
- Sat Mar 30, 2024 4:16 pm
- Forum: Hybrid Cannons
- Topic: Hybrid velocity
- Replies: 20
- Views: 3116
Re: Hybrid velocity
Yeah I noticed the multi-piece design, I was just wondering if the air hitting it broadside at ~6000mph would vaporize it. Though thinking if it now, if it can withstand the gforces of the initial shot, that should have been obvious. I've been working through a design that wouldn't necessitate a sac...
- Sat Mar 30, 2024 2:37 pm
- Forum: Hybrid Cannons
- Topic: Hybrid velocity
- Replies: 20
- Views: 3116
Re: Hybrid velocity
Very interesting. At those velocities, does the sabot shatter on exit? I would be lying if I said I haven't been thinking of ways to pack a 2 stage gun into a rifle-esque design. Quinn, as I've said before, PLEASE post any picture/video/drawing of any of the guns you've built. I would LOVE to see th...
- Wed Mar 27, 2024 1:41 pm
- Forum: Hybrid Cannons
- Topic: Hybrid velocity
- Replies: 20
- Views: 3116
Re: Hybrid velocity
Quinn, please stop. D_Hall, I'll have to learn more about Maxwell-Boltzmann and related topics, thanks. I may be at the upper limits of what can be accomplished with propane, in that case. Given your reasoning for the velocity potential with powder, it would stand to reason that hydrogen/oxygen woul...
- Tue Mar 26, 2024 10:01 am
- Forum: Hybrid Cannons
- Topic: Hybrid velocity
- Replies: 20
- Views: 3116
Re: Hybrid velocity
What are methods of passing beyond the local SOS? I imagine things like raising temperature beyond that of standard combustion or using a fuel whose combustion produces elements with higher SOS, but these are both modifying the SOS limit rather than surpassing that limit. The ~3400fps lines up with ...
- Sun Mar 24, 2024 9:37 am
- Forum: Hybrid Cannons
- Topic: Hybrid velocity
- Replies: 20
- Views: 3116
Re: Hybrid velocity
Are the expanding gasses in a hybrid not limited to local SOS like the released pressure in a pneumatic is?
- Mon Mar 18, 2024 7:07 pm
- Forum: Hybrid Cannons
- Topic: Hybrid velocity
- Replies: 20
- Views: 3116
Hybrid velocity
I have measured upwards of 3355 feet per second with a hybrid I've been working on. Mind you, I'm using a .510" diameter 3d printed 100% infill aerodynamic projectile weighing very little. I highly doubt this is the projectile velocity, and instead is catching debris or even the gasses themselves .....
- Wed Feb 21, 2024 6:54 pm
- Forum: Pneumatic Cannons
- Topic: this my 100th post yay
- Replies: 31
- Views: 3151
Re: this my 100th post yay
There is a sticky in the Spudfiles general forum about exactly this.
- Thu Feb 15, 2024 8:23 pm
- Forum: Pneumatic Cannons
- Topic: this my 100th post yay
- Replies: 31
- Views: 3151
Re: this my 100th post yay
Or a picture/drawing of your pneumatic whose chamber exhibits no pressure loss from each shot.
- Thu Feb 15, 2024 12:47 pm
- Forum: Hybrid Cannons
- Topic: do any of you guys have some tips for hybrids
- Replies: 3
- Views: 551
Re: do any of you guys have some tips for hybrids
Are you just refusing to read ANY of the 'stickies' or previous posts before making all of these threads?
- Tue Feb 13, 2024 12:09 pm
- Forum: Combustion Cannons
- Topic: Combustion cannons
- Replies: 2
- Views: 626
Re: Combustion cannons
Assuming you mean PETN/ETN. Discussion of the use of explosives is not allowed on these forums, to my knowledge. Also, given the level of knowledge you have shown in your multitude of questions on this forum, I'd STRONGLY recommend you do not attempt to utilize this material.
- Tue Feb 13, 2024 12:02 pm
- Forum: Combustion Cannons
- Topic: pnumatic spud guns
- Replies: 11
- Views: 1259
Re: pnumatic spud guns
There is no way to use pressurized air as the energy source and not observe the pressure drop after use. An efficient system may be able to lessen the pressure loss, but it is impossible to eliminate it unless the pressure isn't what's being used as the primary propellant. Many people have used pcp ...
- Wed Nov 29, 2023 4:16 pm
- Forum: Hybrid Cannons
- Topic: Hybrid disk burst pressure effect on performance
- Replies: 23
- Views: 34691
Re: Hybrid disk burst pressure effect on performance
Correct me if this theory is flawed, but could it be more than simply the effective chamber being larger? The unburnt portion of the fuel has mass to it, and so as it's being propelled by the expansion of the burning fuel behind it, it pushes the projectile faster and faster. As the flame front catc...
- Tue Nov 28, 2023 4:32 pm
- Forum: Hybrid Cannons
- Topic: Hybrid disk burst pressure effect on performance
- Replies: 23
- Views: 34691
Re: Hybrid disk burst pressure effect on performance
This is very interesting. Intuitively, the highest pressure accumulated before burst would result in the highest velocity. It would stand to reason, though, that you want the disc to burst late enough to raise the chamber pressure sufficiently, but early enough for there to be unburnt fuel mix being...
- Fri Nov 24, 2023 11:48 am
- Forum: Hybrid Cannons
- Topic: Hybrid geometry
- Replies: 7
- Views: 7153
Re: Hybrid geometry
Pushing my own limits, at least. Really, I'm just trying to get the most possible out of what I make. If I have to stay within a safe pressure limit, I want to do as much as possible while remaining in that limit. My primary interest lies in handheld launchers. I dabbled with large cannons in my you...
- Fri Nov 24, 2023 10:45 am
- Forum: Hybrid Cannons
- Topic: Hybrid geometry
- Replies: 7
- Views: 7153
Re: Hybrid geometry
My chamber walls are around .23" thick, so I should be able to run mixes considerably higher than 15 and remain in a safety margin. (Mathwise anyway) Another thought: have you experimented with an *inner* chamber liner with a lower thermal conductivity than the chamber material? If the largest porti...