A previous build that I still have but is dismantled now was made for 8mm steel ball bearings but I wasn't sure how accurate it was going to be past 25-30 metres being a smooth bore system. While they intuitively sound good, steel balls are quite poor projectiles. First of all, a sphere has quite a...

Does that mean it won't get much quicker with air? Pretty much. Once you're past Mach1 in the working fluid it gets much more difficult for every bit of extra speed. REsult is the gun gets a lot louder, uses a lot more air, and only goes a tiny bit faster. Options are to use a lighter gas (like hel...

First Rule Gentlemen. Yes, very loud even with a silencer. That's right, just basic hammer valve system. Get about 40 shots per fill, don't think I'll continue with Helium though. The cost along with how loud it is doesn't make it worth the small increase in velocity. That's quite a respectable sho...

At 2000 psi I'm getting 1150 fps. Might try 2500 and then 3000 today and see how it goes. OK, yeah, you're Mach1+ for air. That means that the ability of air to literally move it's own self is a major hurdle. Helium should really help things along...And apparently it has! Does that mean it won't ge...

That must make quite a crack! Interesting rifle build, I'm guessing it's a home made hammer valve? Yes, very loud even with a silencer. That's right, just basic hammer valve system. Get about 40 shots per fill, don't think I'll continue with Helium though. The cost along with how loud it is doesn't...

Air2theBrain wrote:Nice..so that fps was achieved with a 2000psi shot of air?

The gauge was sitting on about 2,200 psi of Helium.

Air2theBrain wrote:Chrono pics please

How long is your barrel?

Just got 1320 fps when shooting a 19.09gr pellet.
73.88 foot pounds.

24" barrel.

Best so far is 1198 fps for a total of 58 foot pounds @ 2500 psi from a .22 18.13gr pellet.

Groupings of half inch @ 25 metres.

D_Hall wrote:What are your muzzle velocities?

At 2000 psi I'm getting 1150 fps.
Might try 2500 and then 3000 today and see how it goes.

Pic attached.

Helium is a smaller molecule than Nitrogen or Carbon Dioxide and therefore often has problems with sealing system made for air, but aside from this, the cost and the dangers of a hilarious death if firing repeatedly in a confined space , no other downsides ;) OP, In addition to what JSR said... The...

Air2theBrain wrote:Any chance of a video with you speaking whilst shooting it?

http://www.spudfiles.com/pneumatic-cann ... 26691.html

Haven't got any videos yet but plan to do a couple in the near future, got a few pics though so I'll try and upload them.

Helium is a smaller molecule than Nitrogen or Carbon Dioxide and therefore often has problems with sealing system made for air, but aside from this, the cost and the dangers of a hilarious death if firing repeatedly in a confined space , no other downsides ;) Yes I already knew about it being more ...

Has anyone had experience with helium instead of HPA? My latest homemade air rifle was already performing pretty well with HPA (38 FPE).
Then I tried helium and it increased to 53 fpe!!!
Apart from the cost, are there any other down sides to using helium?