Search found 5401 matches

by Ragnarok
Fri Feb 10, 2017 3:36 pm
Forum: Hybrid Cannons
Topic: Fueling a very high mix hybrid
Replies: 17
Views: 2858

Re: Fueling a very high mix hybrid

Not really my specialty so I'm willing to be wrong and corrected, but I don't think the propane will evaporate as air pressure is applied? That would also be my thoughts. From my general understanding, the phase change is based on partial pressure, and the partial pressure of propane will be the sa...
by Ragnarok
Fri Feb 03, 2017 6:25 pm
Forum: Pneumatic Cannons
Topic: Yet Another Vacuum Cannon and materials selection
Replies: 14
Views: 2513

Re: Yet Another Vacuum Cannon and materials selection

I have 2 questions of any one who has the time, is there an ideal ratio for barrel volume to air reservoir volume? And the same goes for the vacuum accumulator. It depends how you define ideal, but the likely answer is no. Two possible ideals are: - A chamber volume where acceleration falls to zero...
by Ragnarok
Thu Feb 02, 2017 8:10 am
Forum: Pneumatic Cannons
Topic: High Pressure QEV Air Gun
Replies: 4
Views: 2263

Re: High Pressure QEV Air Gun

foot/pounds are a measure of torque, not velocity. Possibly slightly late and off-topic to answer this, but what the heck. While this part is sort of correct, both torque and kinetic energy use units of foot-pound force, being a force multiplied by a distance. (So foot-pounds, not foot/pounds. They...
by Ragnarok
Mon Jan 30, 2017 6:19 am
Forum: BB, Airsoft, and Pellet Guns
Topic: Pneumatic Cylinder For Bolt Action
Replies: 34
Views: 4262

Re: Pneumatic Cylinder For Bolt Action

I must have missed that part. No, it'd be very strange for coaxial pneumatics to be able to use any type of breech loading (including break action).
by Ragnarok
Mon Jan 30, 2017 12:18 am
Forum: BB, Airsoft, and Pellet Guns
Topic: Pneumatic Cylinder For Bolt Action
Replies: 34
Views: 4262

Re: Pneumatic Cylinder For Bolt Action

Ah, of course, but if I flipped the cylinder round :shock: It would, but unless the rod is a fairly large part of the volume of the cylinder (which would be unusual), you wouldn't see massive advantages in the amount of air moved or the pressures reached. sorry but this is where i have to ask, what...
by Ragnarok
Sun Jan 29, 2017 11:34 pm
Forum: Hybrid Cannons
Topic: Links
Replies: 4
Views: 1026

Re: Links

In response to your PMed question (if it's not a question I specifically need to answer, it's better kept to the main forum): Generally the pilot volume on a piston hybrid is vented by a "spool"-type piston with two sealing faces (one between the chamber and the barrel, and the other connecting the ...
by Ragnarok
Sun Jan 29, 2017 10:48 am
Forum: BB, Airsoft, and Pellet Guns
Topic: Pneumatic Cylinder For Bolt Action
Replies: 34
Views: 4262

Re: Pneumatic Cylinder For Bolt Action

I'm not entirely sure. It's possible it's a coaxial configuration.
by Ragnarok
Sun Jan 29, 2017 9:14 am
Forum: BB, Airsoft, and Pellet Guns
Topic: Pneumatic Cylinder For Bolt Action
Replies: 34
Views: 4262

Re: Pneumatic Cylinder For Bolt Action

now I am wondering if this would work, the reduced bore rod side would act as a precharge pump It won't. In a double-acting configuration like this, the first stage would need to have a higher volume than the second, else you're not increasing the pre-charge pressure in the second stage. Here, the ...
by Ragnarok
Sat Jan 28, 2017 8:15 am
Forum: Hybrid Cannons
Topic: Links
Replies: 4
Views: 1026

Re: Links

Generally, hybrids are considered to be something of an "if you have to ask, don't ask" affair. Anyone who hasn't got the experience to figure most of it out on their own is likely to overlook something when following a tutorial. If you have more specific questions about how certain aspects work, fe...
by Ragnarok
Thu Jan 19, 2017 8:43 pm
Forum: Pneumatic Cannons
Topic: Semi auto barrel/ loader ideas
Replies: 1
Views: 865

Re: Semi auto barrel/ loader ideas

I'd probably suggest a simple blow-forward bolt, as it's fairly reliable and works well for spherical ammunition like that, although it does increase the dead-space between the valve and projectile. Blow-back loaders tend to need more fine-tuning, and a pneumatically operated bolt would be rather ov...
by Ragnarok
Sat Jan 14, 2017 10:12 pm
Forum: General How-To & Discussion
Topic: Short question topic
Replies: 1488
Views: 123030

Re: Short question topic

The QB78/9 have a really long barrel, I rarely see one so long in modern PCPs, maybe because they are designed for CO2? It's possibly a factor. CO2 is after all generally less powerful, given the lower pressures available. Anyway, I do think that a PCP is going to be able to make use of a longer ba...
by Ragnarok
Sat Jan 14, 2017 9:40 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2423
Views: 181440

Re: "In the world of spuds today"

Yes, I did get accused of being involved in the JFK assassination. The Mythbusters did, as I recall, try small airguns as a possible way of delivering poisoned pellets, but they didn't give the airguns a chance with the ice bullets. Mind you, their air cannons were seldom very impressive. I figure s...
by Ragnarok
Sat Jan 14, 2017 5:38 pm
Forum: General How-To & Discussion
Topic: Short question topic
Replies: 1488
Views: 123030

Re: Short question topic

wyz2285 wrote:So for a PCP there would be such a sweet spot too right?
There will be, but it's difficult to say where that is.

My gut feeling is that taking that much off the barrel of a PCP will cost you velocity - a back of the envelope guess would be around 10-15%.
by Ragnarok
Sat Jan 14, 2017 1:09 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2423
Views: 181440

Re: "In the world of spuds today"

Something I cooked up in response to a snowball machine gun video a friend shared on Facebook:
[youtube][/youtube]
by Ragnarok
Thu Jan 12, 2017 9:21 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2423
Views: 181440

Re: "In the world of spuds today"

Oh, I'm sure I could, but by my count I've already got enough unfinished projects to last two lifetimes. :roll: