16 replies to this topic

[Coop]

I use OMC's thick walled PETG for my air guns because my darts fit semi-loose in it. My darts expanded at the last war I went to so I built a breech for it because gravity wouldn't drop the darts down. I know there is something similar to this with an O-ring already posted, but I hate o-rings.


Cut a piece of 1/2" PVC. The length will vary on your barrel length. Mine is about 9".


Cut your dart port. This will vary in length and location depending on your blaster and dart length. My port is about 2" long.


I also rounded off the edges with this cone bit on my dremel.


Now get .5" of 19/32, .5" of 9/16, and 1" of 17/32. You can substitute e-tape for the 9/16 and 19/32, but I had extra brass laying around and like the support.


Super glue them together so the 9/16 and 19/16 are together and the 17/32 is half-exposed.


Add e-tape around the 19/32 to fit snugly into 1/2" PVC.


Super glue this piece into the back of the breech. I only applied super glue to the electrical tape and then shoved it in to prevent super glue from getting on the 17/32. Super glue on the 17/32 would negatively effect the PETG seal.


Get a piece of PETG (mine is 12") and wrap some electrical tape around to fit a piece of PVC on to. *This will also vary in length depending on your other piece of PVC's length and the length of the PETG. Mine is 2.5" long


Super glue the PVC onto the PETG.


Add electrical tape at various point in the PETG for stability in the PVC. This doesn't need to be air tight or cause resistance.


If you choose not to add the string, this is finished.


Get a piece of string and burn the edges to prevent fraying. My string is 11" long.


Secure the string to both pieces of the breech with electrical tape.


This will prevent the barrel from coming out of the breech. There isn't as much friction on the barrel as there would be in a brass breech, so this could be a problem without the string.


This is the finished breech in my BBBB.


I have no difference in range compared to my normal PETG barrel. I really like how easy it is to use, and the seal from the PETG to 17/32 brass is great.

*The string is really only needed if you put the dart port so far forward like I did. I only put it there because this breech is only for my non-minimized BBBB. If you put this on an exposed coupler, there should be enough room in the PVC for the barrel not to slip out. I won't be making any more of these though, so I won't be able to test it. (I think breeches are lame in general and speedloaders/turrets are much more efficient)

Edited by Coop, 30 August 2009 - 01:26 AM.

[1337]

Nicely done. Others, including myself, have done something like this in the past, but i've never seen a writeup.

I like the use of 9/16 and 19/32 instead of E-tape.

Also, the idea with the string is cool as well.

[Coop]

Nicely done. Others, including myself, have done something like this in the past, but i've never seen a writeup.

I like the use of 9/16 and 19/32 instead of E-tape.

Also, the idea with the string is cool as well.

Yeah, I've done similar things too, I just haven't seen anything posted before and didn't know if anyone else did it.

Thanks for the compliments.

[Lt Stefan]

Hmm. I never thought of string as a way to keep the barrel from coming out. A little too "dangly" for me though.

Edited by Lt. Stefan, 30 August 2009 - 01:07 AM.

[Icespartan 1114]

Very nice and creative coop. I also agree with you that a turret/speed-loader is more effective then a breech. Also i have one thing i saw in your last picture that confused me. Why is the there a rubber band on the your pump handle?

[Coop]

Why is the there a rubber band on the your pump handle?

That is an idea I picked up from Minsc at the last war I went to. It's to hold the pump handle in place when firing. It's not enough pressure to get annoying when pumping, but it prevents the pump handle from "dangling" in the extended position.

[Lt Stefan]

Ignore

Edited by Lt. Stefan, 30 August 2009 - 01:26 AM.

[alextwin007]

I used fishingline rather then string on the breaches I mad a while ago. It's a nice little extra that I used on my breaches that I forgot to share with the NIC.

[Hi Yah]

I believe ofallthenerf posted a writeup on a very similar petg breach about a year ago.

[Coop]

I used fishingline rather then string on the breaches I mad a while ago. It's a nice little extra that I used on my breaches that I forgot to share with the NIC.

Other people have posted this idea before, I didn't claim it as my own.

I believe ofallthenerf posted a writeup on a very similar petg breach about a year ago.

Yes, I missed it when I searched for a PETG breech. This is his, but it's not with 17/32 brass, it's with etape holding the seal which, in my experience, doesn't last long.


I'm not saying "Zomg, I'm so original everyone give me brownie points!", I'm just sharing little changes to other breeches that make them better.

[Bedhed117]

Very nice. I especially like the string thing. Nothing pisses me off more than when your reloading on the run and you drop your barrel part of the breech. THis is a cool simple way to solve that problem.

[flamincows]

I made a breech a few weeks ago that seals in the same way, but it required a little too much force to slide the PETG onto and off of the 17/32 for my liking. Have you had this issue?

Also, I found that it doesn't work for my darts which fit tightly in OMC's thick wall PETG as the 17/32 tended to pinch and rip the backs of my darts.

[TantumBull]

Also, I found that it doesn't work for my darts which fit tightly in OMC's thick wall PETG as the 17/32 tended to pinch and rip the backs of my darts.

Crimp the 17/32 brass inwards so that doesn't happen.

Coop: Nice, I like these breeches. I've been using 'em for a while now and they're great.

[Lt Stefan]

Personally I don't like the brass though because my darts tend to slip through, especially if its a tight barrel like CPVC. And o-rings create less dead space. Not that 3/4" matters though. Nice breech.

[Coop]

1) I made a breech a few weeks ago that seals in the same way, but it required a little too much force to slide the PETG onto and off of the 17/32 for my liking. Have you had this issue?
2) Also, I found that it doesn't work for my darts which fit tightly in OMC's thick wall PETG as the 17/32 tended to pinch and rip the backs of my darts.

1) No, I don't think it is too much force. It is a bit more friction than on a brass breech, but it needs to be air tight.
2) I don't drop the dart in and push the barrel back, I actually load the dart into the barrel, so I don't have this problem. You could also use pipe cutters and cut the exposed part of 17/32 to the dart doesn't get cut. This will also solve/help your tightness problem.

1)Personally I don't like the brass though because my darts tend to slip through, especially if its a tight barrel like CPVC.
2) And o-rings create less dead space. Not that 3/4" matters though. Nice breech.

1)Hm, I don't think I fully understand what you mean in your first comment. My darts don't "slip" through 17/32 brass, they have to be pushed...hard. So when I load the dart into the PETG, there is no "pushing" force trying to get the dart into the 17/32. This isn't a problem for me.
2) I have a better seal with the 17/32 brass than with an o-ring. It's ok, I'm not trying to be like "my breech is better than yours", but it seems you're getting defensive over it.

Edited by Coop, 07 September 2009 - 03:51 PM.

[Lt Stefan]

I'm not trying to be defensive. Just making a statement. And I forgot we were dealing with PETG. In that case my darts would never slip through the crimped brass.

[minsc]

Nice work, but I'm not a fan of the paintjob.

Life would be so much easier with a dremel... but that's another story.