Ahoy Mr BlackBeard, riddle me this.....

[Shed tuner]

76x25mm stroke, 7.3x3.8 port. 787/805 with 8.4s / 7.9s, so a tad slammy

I could reduce piston weight, or spring preload, but I had another *identical comp tube but with a 3.5mm port, so tried that....
Same powerplant in the 3.5 ported comp tube gives 773/791

Both are exactly 14 fps down (I didn't fiddle the numbers, honest) - I would have expected the differential between the two to favour the lighter pellets, but it seems to have taken power equally from both ?

Any ideas on why ?

Cheers, JB

* As the tubes are different even though the piston fit felt the same, there could obviosly be some differences in power/frinction.sealing, but it's the differential between the 8.4s and 7.9s that I'm interested in...

[Black Beard]

Sorrry about not replying earlier, I've been busy.

Off the top of my head, dunno. If it was a pcp I would have expected the smaller transfer port to favour the heavier pellets. But it isn't and the smaller transfer port and heavier pellet both make the piston bounce sooner and drop the barrel pressure.

Based on a bunch of assumed dimensions/properties I can make the model get around those numbers. The heavier pellets need a lower release pressure (lower diameter/thinner skirts) and the second cylinder needs a bit more friction in the system. Is this anything like reality? If so then I think it is the lower release pressure is letting more air through earlier so it favours a slightly more efficient part of the cycle.

Best way to measure the release force (pressure) is to pull out the insides and use a cleaning rod to push a pellet past the breach. Push the cleaning rod on a set of kitchen scales to find the force.

BB

[rhyslightnin]

And then re calibrate the spring to the force of the third node of the cryostaticated flux ionized sporadic conensated insorator.., this should cause a momentary collaps of the ionosphere suppounding the plasmatic piston seal.., thus explaining your 14fps drop but only to an accuracy of .000126754395632689873574 x10/3 of a percent of the original fps.., (i guess its Bronx crazy that this biblicaly large number happens to be 14! There must be some kind if Fibonaccised conceptual variation of the answer to life the univers an everything involved) if your having trouble measuing this, a large conical receptacle wooed 30clx45cm in capacity, of merlot should help. A 2004 has a higher acid content by .04% over the mote recent bottles but it has a few other properties that aid beondificative thinking..,
coupled with a large dose of somthing else... will alow a new view into the subject.
U can't think of the exact answer now neither can I so il just drink more merlot!
Happy raster..... I mean Easter all

Anyone know what's the best paint to camo effect my silencer??? Or which is best...., .177 or .20???!!

[pacific marlin]

What he said.
























Oh.......Dulux and .20

[Shed tuner]

Sorrry about not replying earlier, I've been busy.

Off the top of my head, dunno. If it was a pcp I would have expected the smaller transfer port to favour the heavier pellets. But it isn't and the smaller transfer port and heavier pellet both make the piston bounce sooner and drop the barrel pressure.

Based on a bunch of assumed dimensions/properties I can make the model get around those numbers. The heavier pellets need a lower release pressure (lower diameter/thinner skirts) and the second cylinder needs a bit more friction in the system. Is this anything like reality? If so then I think it is the lower release pressure is letting more air through earlier so it favours a slightly more efficient part of the cycle.

Best way to measure the release force (pressure) is to pull out the insides and use a cleaning rod to push a pellet past the breach. Push the cleaning rod on a set of kitchen scales to find the force.

BB

Cheers BB...

Both pellets (7.9s and 8.4s) are JSBs, virtually identical in all except weight, and are generally a very good test/measure of slam/bounce for that reason. However I do find the 7.9s, if anything, slightly easier to push home - which is kinda the opposite of what we were looking for

I'll try and retest using the same tube, swapping the end plugs around, to get that out of the equation...

As to the other replies, bit over my head - I think we'll keep it simple

Tks - JB

[richardscar]

And then re calibrate the spring to the force of the third node of the cryostaticated flux ionized sporadic conensated insorator.., this should cause a momentary collaps of the ionosphere suppounding the plasmatic piston seal.., thus explaining your 14fps drop but only to an accuracy of .000126754395632689873574 x10/3 of a percent of the original fps.., (i guess its Bronx crazy that this biblicaly large number happens to be 14! There must be some kind if Fibonaccised conceptual variation of the answer to life the univers an everything involved) if your having trouble measuing this, a large conical receptacle wooed 30clx45cm in capacity, of merlot should help. A 2004 has a higher acid content by .04% over the mote recent bottles but it has a few other properties that aid beondificative thinking..,
coupled with a large dose of somthing else... will alow a new view into the subject.
U can't think of the exact answer now neither can I so il just drink more merlot!
Happy raster..... I mean Easter all

Anyone know what's the best paint to camo effect my silencer??? Or which is best...., .177 or .20???!!

Sorry Rhys that last question recked my head ! lol , cant help you with that one