Page 2 of 2
Re: BBMG trouble
Posted: Sun May 02, 2010 11:32 pm
by jackssmirkingrevenge
Lockednloaded wrote:In JSR's burst fire bbmg, he uses a tiny cloud chamber, but i do not like this due to reloading issues, but with a large cloud chamber would this concept really work?
It will work but in a larger cloud chamber, you will lose power due to gas expansion. some sort of seal/detent at the breech will rectify this
100 psi is probably too much if you want to use this for airsoft. Remember that the power of BBMGs lies with their concentrated weight of fire, which you have to consider apart from individual projectile strength.
[youtube]
[/youtube]
In the case above, a single BB does not have the power to penetrate the aluminium plate but the repeated impacts in a short time in a small area are enough for the stream to chew through.
Posted: Mon May 03, 2010 12:02 am
by kydavies
so when the first bb hit the aluminium it severly dents it which in reality is stretching the molecular bonds almost to the breaking point and the next bb is to punch through right...
Posted: Mon May 03, 2010 12:14 am
by jackssmirkingrevenge
kydavies wrote:so when the first bb hit the aluminium it severly dents it which in reality is stretching the molecular bonds almost to the breaking point and the next bb is to punch through right...
That's the theory, think of it like a jackhammer
the example I always mention is the
American 180 22LR submachinegun:
[youtube]
[/youtube]
In spite of using the humble rimfire round, it was still an effective law enforcement (and
military in the Balkans) weapon because of its high rate of fire (20-25 rounds per second) and magazine capacity (up to 275 rounds!), and some articles claim it was also capable of defeating body armour with concentrated bursts.
Posted: Mon May 03, 2010 12:31 am
by kydavies
k sweet, also to improve the rate of fire of a cloud or vortex you could shape the resovoir like a cigar so the bbs flow nicely into the barrel
Posted: Mon May 03, 2010 12:38 am
by jackssmirkingrevenge
kydavies wrote:to improve the rate of fire of a cloud or vortex
Frankly I think they fire fast enough as it is - Jimmy had
measured ROF of his BBMG at an average of over 50 per second, if anything much of the development on this forum has been geared towards reducing that amount
Posted: Mon May 03, 2010 12:45 am
by kydavies
ya, but why not its always fun to be on top
Posted: Mon May 03, 2010 1:00 am
by jackssmirkingrevenge
kydavies wrote:ya, but why not its always fun to be on top
It's more fun to increase projectile energy than rate of fire. Compare my other video with this of a BBMG ramped up to 800 psi:
[youtube]
[/youtube]
No need for the BBs to "chew through" the same aluminium plate, a single one will happily go straight through
Anyways, this is turning into a thread hijack so I digress...
Posted: Mon May 03, 2010 10:43 am
by Mr.Sandman
kydavies wrote:wth minei run it at 40 to 80 psi (depends on what im shootingat) and the spread is a result of you movingthe gun slightly between each bb comming out. rememberi ts not like a shotgun where all the pellets come out at the same time, each bb leaves the barrel seperatly so spread is a result of a combonation of the following: you moving the gun ever so slightly, inconsistancy in the ammunition, each bb is also fired at a slightly different pressure so the trajectory is affected, and also barrel movement ifyou barrel is not firmly attached. look up 2nd 6mm vortex and watch the video of mine and a pic which might give yu some help, sorry about all the spelling errors, im doing this from my ps3 andi have a tiny keyboard. edit: im guessing if your barrel end vortex cap was shaped like a cone you would have a much higher rate of fire because the bbs would hve a greater chanceof entering the barrel at a higher velocity. just a theory.
Honestly speaking you aren't on the right page with us.
Edit: And .12 gram bb's are garbage and inaccurate.
For one thing bb spread can also be the cause of the nature of a bb. Bb's are some of the least consistant types of ammo. Also a barrel with bad tolerances such as brakeline can also cause bad accuracy. Also you a cone shaped vortex block would do nothing for performance.
Posted: Mon May 03, 2010 12:14 pm
by kydavies
k i may have been a wee bit off but i was trying to give some help, also when i get around to it im going to test a cone shape vortex chamber just for kicks and because i believe it might work better
Posted: Thu May 13, 2010 9:56 pm
by Lockednloaded
the piston idea may be scrapped because if there is not enough evidence to prove its air efficiency compared to just tapping the blow gun lever for burst fire. just obtained a 720psi tested fire extinguisher and a regulator.