2240 arrow gun

[nutshot]

Been faffing about with my 2240 this afternoon. Not quite finished yet but heres a picture.



Its sort of running just not overly powerful. Ive not got a transfer tube fitted yet so its got a major blow and I`m loosing a lot of gas from the breach. If I get time tomorrow I`ll make a transfer tube and do a few mods to the valve to up the gas flow then test it for power. 

[Pellethuntr]

Thats coo, do you have any more pics? Inquiring minds want to know 

[bradyman1]

Looks like you put some work in to that. What is your primary use for it?

[nutshot]

Ill get a load of picture taken of it in pieces .
I had a play with it last night and the stainless steel hammer I made doesn`t like the huge spring Ive fitted so Ive got to sort that out . Ive found my original hammer out so Ill mod that with it being hardened . Im going to port the valve as much as I can then make a transfer tube to stop the breach blow . I`m probably loosing about 50% of the gas through the sides of the gun at the moment .
The barrel/ tube is a bit of 303 stainless I turned down to just under 5.5m so a standard 6 1/2" crossbow pistol bolt with the nock removed slips over the top . I drilled it with a 3mm bore which is as big as I can go without making the tube too weak . The aluminium shroud is just to protect the thin tube.
Power is &^^& and no where near the power of an 80lb pistol crossbow . at 10 ft it sticks into cardboard about 1/4 the depth of the crossbow . Should be a lot better when I make the transfer seal .

I made it just for fun as I had a 2240 I didn`t use and had already butchered to run on magnets instead of a hammer spring . The magnets didn`t give me any where near the power I needed for bolts so Ive reverted back to a normal hammer spring. Its now got a full length fac theoben rapid spring in .

Heres a couple of pictures of the tube etc





And the 6 1/2" crossbow bolts it shoots



Found out Ive got to work today so it depends on what time I finish to whether I will get any more done on it today .

[bradyman1]

That is a pretty cool toy. If you can get it shooting harder it will be awesome. How tight does the inside of the arrow fur to the gas tube? If it us too loose you may be loosing some power there also.

[nutshot]

The tube is not a loose fit, its not tight ether. The bolt will drop on the tube with its own weight but stays there with the length even when pointed a long way towards the floor. If I had gone any tighter I think I would have had too much friction . I`m approximately 0.1 mm thinner on the od of the tube than the id of the bolt. 
I found a possible better way to make a barrel tube using brass micro tube from hobby shops . Each size slides inside the next so you can start with a 5.5mm od tube then internally sleeve it to strengthen it and reduce the bore . The 5.5mm tube will be fractionally too large for the bolts but that could be easily reduced with some very fine wet and dry abrasive paper as taking off 0.1 mm would be hard to do on the lathe.

I think the only problem with the power is the leak at the breach . If I put my finger over the tube most of the gas shoots out the sides of the gun . lol . Hopefully it will shoot somewhere in the 150-200 fps region when I fix the leak which will make it similar to an 80lb crossbow pistol. Bolts weigh around 100 grain so would give it about 6-8 ftlb . If it doesn`t work it was fun trying

[1377x]

interesting

[nutshot]

Finally got a chance to do a bit more on the 2240 arrow gun. Got the transfer port sorted so no more leaks and all I can say is WOW . Its got a decent amount of power now.
Not quite sure how much but the bolts stick in my garden fence at 20 yards

I threaded the valve to have a screw in transfer port so it now does 2 jobs and works as the valve retainer too .





I also butchered a retaining spring from a broken crossbow so now no matter what the angle the bolt will not drop out



And here are another couple of random pictures of the breach , barrel and shroud .







One final strip now it works great just to tidy up a few rough edges . Will probably spray the shroud and breach black as I can`t really be bothered to spend time anodizing them .
I will put a couple of final pictures up over the weekend all complete and do a chrono test and maybe a video of it shooting  

Rule #6 violation

[bradyman1]

Really cool project. I would like to see a video of it.

[Pellethuntr]

Really cool project. I would like to see a video of it.

+1  Cool project Nutshot

[nutshot]

Put the finishing touches on it this afternoon. Power is 160 ish fps , about 6 ftlb with a 103 grain bolt . It was running more before but I decided to polish the valve stem and after that it started dumping all the gas with 1 shot ? weird ?? so I have had to back the hammer spring off a touch . Not a bad thing really as now I am getting about 20 decent shots per 12 gram where before it was about 5 shots . Might have another play with the valve and spring settings another day but I`m just going to have some fun with it for a bit now .

Heres a couple of pics of it all done . Will put a video up shortly as soon as I find out how to get it working ? windows movie maker keeps crashing on me

[1377x]

that has to be one of the coolest 2240's i have seen
nice job!!!

[nutshot]

Glad you think so 1377
I just enjoy the making side more than anything else. Ive got another couple of air guns on route which I have bought in bags and all apart. not sure what I am going to do with them yet but if I think of something interesting I`ll post it . Maybe an airgun that shoots blow gun darts next or a rifle length arrow gun being as this turned out so well .

Heres a video of it shooting . Its not turned out great as the bolts go a bit too fast for my iphone to see them . I did get a lot more footage but unbeknown to me my phone had blown over in the wind and videoed the floor 

Range was about 10 feet .

[1377x]

nice video! william tell
those arrows are moving faster than i thought they would
awsome gun!

[Bent]

Nice.. Maybe a fun project for this winter.... 

[mmaMonster]

nice.

[Wheelman88]

Very nice project gun!