Search found 1918 matches

by D_Hall
Sat Jun 29, 2024 11:59 am
Forum: General How-To & Discussion
Topic: GGDT/HGDT Request Thread
Replies: 117
Views: 242388

Re: GGDT/HGDT Request Thread

Free web hosting or not is irrelevant. The money is a complete non-issue. The catch is that this is likely my last forray into spud guns. I'll likely write the new tool, put it out there for the community to do whatever it sees fit with it, and not really think about spud guns again. Having a web pr...
by D_Hall
Fri Jun 28, 2024 6:29 pm
Forum: General How-To & Discussion
Topic: GGDT/HGDT Request Thread
Replies: 117
Views: 242388

Re: GGDT/HGDT Request Thread

But now someone is on the hook for maintaining the web presence, no?
by D_Hall
Fri Jun 28, 2024 5:40 pm
Forum: General How-To & Discussion
Topic: GGDT/HGDT Request Thread
Replies: 117
Views: 242388

Re: GGDT/HGDT Request Thread

Yes, I actually looked at doing it in Python a couple years ago. The biggest issue was that Python is generally not compiled and you have to install the IDE for it. Well, that's all well and good except that only geeks actually have done so. Meanwhile, pretty much everyone and their brother has a sp...
by D_Hall
Thu Jun 20, 2024 9:25 pm
Forum: General How-To & Discussion
Topic: GGDT/HGDT Request Thread
Replies: 117
Views: 242388

Re: GGDT/HGDT Request Thread

Not really a question but some commentary.... Obviously, it's been a very long time since I wrote GGDT/HGDT. I've learned a lot since then and I think I could do a better job. I've spent a lot of time thinking about things. If I rewrote them, how would I do it? Well, first and foremost I would creat...
by D_Hall
Sat Apr 13, 2024 1:39 am
Forum: Pneumatic Cannons
Topic: Couple quick Noobie Questions and advice.
Replies: 4
Views: 1571

Re: Couple quick Noobie Questions and advice.

1) Any general thoughts or concerns to the overall design? Probably charge it to 100psi max. Always remember that PVC is prone to cracking if mistreated. In other words, while a PVC barrel can be done, the larger it is the more cognizant you have to be about its treatment. Be nice to it lest it gren...
by D_Hall
Sat Mar 30, 2024 11:10 pm
Forum: Hybrid Cannons
Topic: Hybrid velocity
Replies: 20
Views: 6345

Re: Hybrid velocity

Well, the biggest issue is "How do you STOP the piston in the pump stage?" If you're soft stopping it, that implies your piston velocities aren't very high which in turn implies that your pressures aren't very high which in turn means your velocities won't be very high which in turn begs the questio...
by D_Hall
Sat Mar 30, 2024 3:45 pm
Forum: Hybrid Cannons
Topic: Hybrid velocity
Replies: 20
Views: 6345

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. Well, they're multi-piece designs that are literally held together by the bore of the gun. The moment they're clear of t...
by D_Hall
Thu Mar 28, 2024 6:54 pm
Forum: Hybrid Cannons
Topic: Hybrid velocity
Replies: 20
Views: 6345

Re: Hybrid velocity

Hint: Side 7 has the title "Typical FI Laboratory Gun Sabot" and photographs of 2 different sabot designs.
by D_Hall
Thu Mar 28, 2024 12:17 am
Forum: Hybrid Cannons
Topic: Hybrid velocity
Replies: 20
Views: 6345

Re: Hybrid velocity

Yes, H and O are great. That's why you see 'em used in rockets. For bonus points, run it just a bit fuel rich and you get even lower molecular weight without much loss in temperature. And yes, that's why rockets run such. The same physics apply! That said, running H/O in a gun at anything that resem...
by D_Hall
Tue Mar 26, 2024 9:04 pm
Forum: Hybrid Cannons
Topic: Hybrid velocity
Replies: 20
Views: 6345

Re: Hybrid velocity

What are methods of passing beyond the local SOS? The previously mentioned exploitation of Maxwell-Boltzmann distributions. Highly inefficient and has it's own limitations. Not useful for much more than braggin' rights. I imagine things like raising temperature beyond that of standard combustion or...
by D_Hall
Sun Mar 24, 2024 7:43 pm
Forum: Hybrid Cannons
Topic: Hybrid velocity
Replies: 20
Views: 6345

Re: Hybrid velocity

A few thoughts in no particular order.... 1 - Post-combustion chemistry absolutely matters. It can drastically alter the local sonic velocity. 2 - Traditional powder-based guns can go much faster than OP's listed 5200 ft/s. I've personal experience with a gun that runs at 8,900 ft/s. 3 - I'm a bit b...
by D_Hall
Sun Jan 28, 2024 2:00 pm
Forum: SpudFiles Discussion
Topic: GGDT and HGDT
Replies: 22
Views: 38410

Re: GGDT and HGDT

Jack got it right.
by D_Hall
Sun Jan 21, 2024 7:26 pm
Forum: SpudFiles Discussion
Topic: GGDT and HGDT
Replies: 22
Views: 38410

Re: GGDT and HGDT

I didn't keep anything, but if you've a specific question I'm likely to be able to answer it.
by D_Hall
Sun Jan 14, 2024 2:03 pm
Forum: Pneumatic Cannons
Topic: Where to download GGDT
Replies: 3
Views: 8514

Re: Where to download GGDT

I don't remember where it's stashed, but it's actually on this site somewhere....
by D_Hall
Thu Jan 11, 2024 7:11 pm
Forum: Off-Topic Hobbies
Topic: My current hobby: Cowboy Action Shooting
Replies: 24
Views: 101543

Re: My current hobby: Cowboy Action Shooting

And as a minor brag, I set a new personal best last weekend....



...Still not going to win any championships, but I felt really good about that run.