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All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Show us your Custom Airgun Parts (TRICKS-N-TIPS) => Topic started by: David.Soliman on March 08, 2014, 06:06:01 PM

Title: CO2 rifle project
Post by: David.Soliman on March 08, 2014, 06:06:01 PM
I'm currently working on a CO2 rifle with a very innovative yet extremely bolt design, one that I have never seen on an airgun before. The gun will use 2 12g CO2 cylinders for power. The whole gun is built out of four stock metals a 25 mm aluminum rod, aluminum tube with a 25 mm OD and 10 mm ID, aluminum plate 15 mm x 25 mm and 3mm thick steel plate, oh I forgot and some scrap steel rods. The gas chamber is 14 mm wide and 45 mm deep, which adds up to a volume of 6.93 cc not including the valve stem and spring. Finishing this gun is going to be a lengthy process since I can only work on it during weekends.
I did manage to get some parts finished but didn't take any photos yet, will do that soon.

I have a question though, what is the maximum power that these CO2 cartridges are capable of?
Title: Re: CO2 rifle project
Post by: rsterne on March 08, 2014, 07:08:12 PM
The gas in a 12 gr. CO2 cartridge, when expanded at room temperature, will occupy a volume of 400 cu.in., so at 1 FPE/CI (which is good efficiency) that would be a total of 400 FPE.... as in 20 shots at 20 FPE would be very good performance.... I read somewhere that in theory there is over 6000 FPE inside a CO2 cartridge, but I don't believe it....

If you are talking about using all the CO2 in just ONE shot, however, you will never approach the 400 FPE level.... not even close....

Bob
Title: Re: CO2 rifle project
Post by: sixshootertexan on March 08, 2014, 07:08:56 PM
What caliber do you plan on the rifle to be?
Title: Re: CO2 rifle project
Post by: David.Soliman on March 09, 2014, 12:04:08 PM
The gas in a 12 gr. CO2 cartridge, when expanded at room temperature, will occupy a volume of 400 cu.in., so at 1 FPE/CI (which is good efficiency) that would be a total of 400 FPE.... as in 20 shots at 20 FPE would be very good performance.... I read somewhere that in theory there is over 6000 FPE inside a CO2 cartridge, but I don't believe it....

If you are talking about using all the CO2 in just ONE shot, however, you will never approach the 400 FPE level.... not even close....

Bob

Thanks Bob I was waiting on your input.


What caliber do you plan on the rifle to be?

Planning on .177, barrels are not sold where I live (Egypt) so I will have to use a barrel off an old gun, one that I'm sure of it's accuracy.

Here are the parts that I've finished:
Aluminum does look ugly right off the lathe.



(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140309_160240_zps28570a01.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140309_160240_zps28570a01.jpg.html)



A couple of O-rings later:



(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140309_160546_zpsc546ce34.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140309_160546_zpsc546ce34.jpg.html)



End cap (no knurling for me thank you) the piercing head fits here:


(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140309_160613_zps5266c499.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140309_160613_zps5266c499.jpg.html)
 



The valve still has a long way to go:



(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140309_161928_zps75d173de.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140309_161928_zps75d173de.jpg.html)



Assembled is almost twice as heavy.



(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140309_160851_zps7ae526d2.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140309_160851_zps7ae526d2.jpg.html)
Title: Re: CO2 rifle project
Post by: David.Soliman on March 13, 2014, 12:29:57 PM
Slowly getting there.

I call it the lock plate, it locks the bolt in place


(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140313_170246_zps8baa6589.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140313_170246_zps8baa6589.jpg.html)



(http://i1240.photobucket.com/albums/gg482/karammahroos/CO2%20project/20140313_170316_zps920adb51.jpg) (http://s1240.photobucket.com/user/karammahroos/media/CO2%20project/20140313_170316_zps920adb51.jpg.html)