.22 300-400 psi air rifle

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Clarke
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Fri Jul 09, 2010 9:53 pm

I have had this gun sitting for a while and thought id finally finish it with a coat of paint and post it up.

Its a simple 1/2" QEV with a lightly rifled barrel. The chamber is a 1/2" thick by 12" long braze welded togeather. I tried using phoz copper as filler but found the brass to be too dirty and was rejecting it so i switched to some plain old brass and flux with some good results. The Chamber was left at 1200psi for 1 hour with no leaks so very happy.

The .22 barrel is o-ringed and can be removed from the surrounding 3mm thick by 9mm bore stainless steel barrel so 9mm buckshot BB can be used also. The SS outer barrel is a bolt action with a TIG welded spring steel bolt arm that locks on the bolt catch.

It also has a few goodies like bipod, 2x6x28 scope, field strap and a silencer with a removable core for use with the mentioned 9mm buckshot BB's. Its a real accurate plinker averaging a 2-2.5" grouping at 15 meters. It usually run it at 300 psi with my HP pump but have a fridgy coming along and feel comfortable taking it up to 400 psi.

Its loosely based on the RWS 350 Pro Mag but with a stainless barrel and a thumbhole stock. It is very powerful for a small calibre airgun and a lot of fun, i will upload some damage pics soon.

Video with a bit of shooting, NOTE the shots taken in this video are at 160 psi only.

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Last edited by Clarke on Fri Jul 09, 2010 10:03 pm, edited 2 times in total.
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spudtyrrant
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Fri Jul 09, 2010 9:58 pm

very clean, nice job. do you know about what velocity you are achieving, again very clean build :wink:
Clarke
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Fri Jul 09, 2010 10:37 pm

Not to sure of the fps or ft/lbs yet as i dont have a chronograph on hand.
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Stolly32123
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Fri Jul 09, 2010 10:39 pm

wow thats great. What do you use for the trigger? and how much did that scope cost?
Clarke
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Fri Jul 09, 2010 10:51 pm

I got the scope of australian ebay for $35 including postage. I have just GGDT the gun and if turns out 758fps with 19.7 ft/lbs of energy at 400 psi and 669fps with 17.2ft/lbs of energy at 300psi. I also make this rifle diesel sometimes for extra fps and its seems like a huge jump in velocity. I also like the puff of smoke and the loud crack, lots of fun :twisted:
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deathbyDWV
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Fri Jul 09, 2010 10:58 pm

Wow, very nice!!! Isn't the thumb hole kinda small though?
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jackssmirkingrevenge
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Fri Jul 09, 2010 11:20 pm

Nicely done, what are you using as a pilot?

Be sure to post the results of upping the pressure ;)
hectmarr wrote:You have to make many weapons, because this field is long and short life
Clarke
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Fri Jul 09, 2010 11:34 pm

Thanks for the compliments so far everyone.

DeathbyDWV; it may look a little small but it is perfect for the shape of my fingers and thumb. Should be noted that the gun could be used for a lefty but would be very uncomfortable.

JSR; the pilot is a 1/2" ballvalve that has been worn in really well resulting in a great trigger not too much tension not too little.It is filled on the pilot side through a hollowed out scrader valve off a road bike tyre.

I really would like to take this gun to 600-700psi but im not sure how the pistion in the qev would hold up. I have a few spare pistons so i might amp up the pressure and see what happens. Dieseling at 300psi the .22 pellet is punching through 4 piece of 1mm galvanised sheeting at 10m which is pretty good for a 5.5mm lead pellet me thinks.
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jackssmirkingrevenge
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Fri Jul 09, 2010 11:47 pm

Nice, I'm sure that the QEV will take whatever any future fridge/AC compressor will put out.

Is the suppressor functional or just an aesthetic addition? How about a full length integral suppressor, along these lines?

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hectmarr wrote:You have to make many weapons, because this field is long and short life
Clarke
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Sat Jul 10, 2010 12:56 am

It should hold up as the pistons are fairly robust and dense.

The suppressor does work on taking off that harsh ppssshhhh sound when the gases are realeased especially the crack when dieseling, but i dont have a decibal figure at the moment.

Wow JSR that full length version looks pretty schmick, what kind or rifle is that. I think that it would have to revamp the stock to get mine looking like that so ill think ill pass mate.

I forgot to add that the stock is comprised of two pieces, the upper and lower. It has been cut in two so the welded brass chamber can be threaded up inside the qev chamber port then re-attach the lower stock when finished.

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This picture shows the stock bolts from the top
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jackssmirkingrevenge
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Sat Jul 10, 2010 1:03 am

Clarke wrote:Wow JSR that full length version looks pretty schmick, what kind or rifle is that. I think that it would have to revamp the stock to get mine looking like that so ill think ill pass mate.
It's a Remington M24 fitted with an A.R.I.E.S suppressor.

Volume is a critical element of pneumatic suppressors, so you could use a larger diameter tube extending to the fore end of the stock to make it more effective, should using it at higher pressures make noise levels intolerable.

Also, the seam in the stock was sort of obvious ;) but well done for making it servicable :)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Lockednloaded
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Sat Jul 10, 2010 1:05 am

you can get your bike pump to 300? what kind is it and where'd you get it
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POLAND_SPUD
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Sat Jul 10, 2010 1:24 am

wow... that's impressive
How about a full length integral suppressor
same here
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django
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Sat Jul 10, 2010 2:18 am

wow!!,I like it :D surely pumping up to such high pressure with that pump( looks like a normal bike pump?!) must tire you out!,I think I'd be using a 20 oz co2 bottle and reg.

Thats what I use on my 9mm Semi Auto,I found after a few shots in a similar pump set up to yours that my shots were inaccurate because I'd exhausted myself from using the pump so went the co2 route.

If I was you I would do away with the Ball Valve Trigger and use one of these Poppet valves instead( a million times better) rated at 300 psi
http://www.globalspec.com/datasheets/26 ... B9CC8489F8

Im In Australia and had no probs finding this valve, buy a 20 oz co2 bottle and get a Paintball reg to reg the pressure down to save the hassle of pumping up the chamber every shot!..

Oh yeh and be super highly carefull who you show this gun to mate and dont get caught with it,the Authorities can fine you up to $10,000 or 5 years in Jail!( maximum sentencing). Highly unlikely you'd get the maximum penalty unless you shot a person or animal and were caught but I believe at the LEAST you'd get a reasonable sized fine......
Fizento
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Sat Jul 10, 2010 1:22 pm

i really like your gun gives me much new ideas of constructing my own ;)
had something like that in mind
the only prob is that i want to open my homemade piston valve with a blowgun but i cant find a right adapter to connect it to my fittings... does anyone know if it is a special diameter or is it standardized size?

greetz!
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