I recently got a Recon because I couldn't stop thinking about the clip potential, especially with a modded clip for more ammo. So I got to thinking of ways to make the breech better on this gun since the plunger assembly is really just crap with all that dead space.
So the idea came to me when I looked at the angel breach and realized what happens without a dart tooth, the dart pushes forward into the barrel. Sadly the Recon lacks this barrel making any breech mod without it mostly useless because of all the dead space in the bolt barrel. I solved this to a degree and added a barrel to the front end for the dart to slide into as you'll see.
1' of 1/2" barrel materials. (I used 1/2" copper and PETG)
Pipe cutters (depending on barrel materials)
1 long-ass straw (or more if you can manage it, I found these pretty easily)
Exacto knife (box cutter, anything similar)
Sorry about the quality on some of this as it was a cellphone cam
So here's the first pic:
Missing the barrel in this. Took out the dart tooth and other unnecessary pieces. As you can see I did some standard Recon mods to start, added a wire to the outside of the plunger mechanism to shorten the spring's length inside the gun of course, trigger pull mod and removed the ARs. (as you can obviously tell since I chopped the barrel off there)
Here's the straw mod, standard mods, again. (also replaced o-ring and used Silicone lube)
And here's where it gets interesting:
So I glued a piece of 1/2" copper to where the breech used to be. I measured the old one and cut a piece of copper to the length it was and also measured where the plastic top piece was located so I could place it properly on the copper (essential or it won't cock/load properly!) The main reasons you'd want to use new material here would be to make sure you've got a good seal between the straw hole end and the barrel you're going to need. The problem with the original barrel is you'd need to cut it down anyway and it's got an upwards curve on the bottom-front part which really would not help the seal with the barrel piece.
This is the point where I actually did the straw mod so it would go through from one end to the other.
I was planning on having another larger pipe to fit over the copper but it doesn't seem to work that well with the plastic sticking out top-front of it like that. (I'm planning on changing it to pump action so I will change the old cocking mechanism)
And this is the new PETG barrel I measured out to specifications based on measurements of the breech/plunger system:
Plunger tube: Length: Inner Diameter: 9cm 2cm Straw: L: ID: 17.75cm 6mm PETG: ID: 1.5cm Equations: Pi * (ID/2)^2 * Length = Volume (Vpt-Vs)/PI * (ID/2)^2 = Length of barrel Plunger tube: Vpt = Pi * 1^2 * 9 = 28cm^3 Straw: Vs = Pi * 0.3^2 * 17.75 = 5.0cm^3 Barrel: L = 23/Pi * 0.75^2 = 13cmSo using these numbers I realized the barrel could be as long as 13cm and it would use all the air from the plunger! So I cut it a little short, wrapped it with electrical tape to fit it snug, gooped it up and shoved it in there tight.
And here's the back of the barrel. The tape on the other end is so it slides into the front attachment and aims properly, I'll show my front barrel and stock mods later as they are old news but I like them anyways. I measured the distance into the gun the barrel had to be by putting the new breech into the gun and pushing as far forward as it's going to go and then I pushed the barrel into the front until it's against the breech front and marked off where it's sticking out the front piece of the gun.
Sorry no ranges yet, still waiting for the barrel to dry completely. So far it seems to work fine otherwise and the only problem I ran into was the darts would catch on the PETG barrel but I can probably fix it up by making a bit of a ramp into the barrel leaving space so the copper bolt doesn't stop short of the PETG.
Also planning on doing other standard mods like the "extra" spring in the stock.
Ranges are stock so far but I am planning to add a stock spring and I should see considerable improvement with extra force on the plunger with this mod!
Questions? Comments? Suggestions? Flames?
Try not to be too harsh please, I can learn!
Edited by 2iko, 06 June 2009 - 10:00 AM.