22 replies to this topic

[Carrtoon]

I've had this idea for a while, and finally got around to trying it out. It's remarkably similar to the Longshot breech, but it gets an almost perfect seal. Here is the blown apart pic:



The male part of the breech where the dart falls onto and the o-ring on the very back:



The female part:



Fitting together:



The outer body:



The closed breech:



The open breech:



The fully open breech looking into the barrel:



The fully open breech looking out the back of the barrel. The lathed aluminum stops the dart and pushes it into the barrel:



And the video showing how it works:

Attached to the titan firing through a cardboard box

It works absolutely perfectly. The male part of the breech is pushed past the edge of the casing, adding to the seal. It uses only PVC and CPVC. I precision lathed down the pieces to fit better than brass. I used the dremel to custom cut the male and female parts, as well as the bolt hole. As soon as I get my crossbow coupler back on, it will be the new reciever of this attachment.

Question: Has this been done before?

Edited by Carrtoon, 04 August 2006 - 06:50 PM.

[tcorr911]

I did the exact same thing but simpler for a homemade, but it just didn't work in the end so I never posted it.

[nerfer34]

Nice carrtoon looks very effective! Uhh something similar to this has been done before I believe, to answer your question.

[NerfMonkey]

I did a breech with CPVC and PVC, but it just used a bolt to push a long barrel forward, and then you had to pull the barrel back so it really didn't help ROF that much. It worked decently, but wasn't very clean or effective.

Your breech is far superior to mine, and I can't think of any other breeches done with CPVC and PVC. That's a nice creation.

[ompa]

The closest I'm aware of that uses something like this is Boltsniper's breech on his BS-9.

Otherwise, what you have there is pretty damn original.

I love it.

I have to make it out to at least ONE of the wars you're attending to see some of these monstrosities.

~ompa

[trogdor65]

Thats a sweet breech Carrtoon! Simple and satisfying.

[Carrtoon]

Thanks guys. It may look simple to some, but it isn't at all. I went through 3 tries and spent a total of about 15 hours on this before I got a working one. The cpvc has to be lathed down perfectly to be able to slide the breech in and out somewhat easily and still keep the seal. Fitting the two ends, male and female, made it even tougher. Those pieces had to fit snug, but not too snug or they would stick and make it almost impossible to pull back and shut when it was put into the PVC casing.

Some may be wondering if you need a perfect seal on the male and female parts. You don't. It should be close, but as you can see from the close up pics, the female end is offset in the PVC by about a centimeter. This allows the pieces to come together inside of the PVC casing instead of on the edge of the breech cut. The seal is great do to that and the o-ring that works behind the bolt.

Some may also want to know why I have the fingers joining in the breech. When a dart drops down from a clip, the dart will land on the two fingers. This allows you to just push the bolt forward instead of having to physically push the dart into the barrel. With brass, you may have jamming darts because the brass transition isn't completely flush. This eliminates that factor because the material is the same size. I can't wait to try a clip! This works so nice I may even be able to use gravity instead of a spring fed clip. The clip also won't have to be air tight. Update soon!

[murakumo32]

I like how you got past the jamming, I did something similar to that.

What I did was simply take 2 pieces of cpvc, take my dremel, and thin the inside walls of the cpvc. It gradually flows into the regular ID of the cpvc and the dart can't load any smoother.

[Carrtoon]

Yep, I did the same thing with the female end. If you look in the 8th picture down, you can see that I dremeled it so the dart would fit it nicely. I also plan to dremel down the top of the male end so darts wouldn't get caught as the breech closed. I guess wood would be the best clip material, eh?

[echo104b]

I look at this and i cant help but think that it's the exact same thing as the Longshot Breech.

You get Mega Bonus points for replicating this tho! i think with this i could do a CPVC Mod vor the Longshot.

Great job!

No more special darts to be affraid of losing

[sam]

I would try to build a clip out of aluminum, since you can get it fairly easily, and its light and sturdy.

[Carrtoon]

Aluminum would have been nice, but my dad's arc welder just blew an expensive board, so I just used a cheap tape case. Here are some videos:

Clip fitting and loading

Emptying the clip

The last shot looks like the dart jammed, but the barrel actually fell off of the crossbow from the vibrations. The crossbow isn't modded with a spring or bungees in the videos, but I can assure you, I can even get a video if you want me to prove it, that the bungeed crossbow with this breech can almost shoot through cardboard. I'm very happy with the results.

[WratH]

Looks great, but what's with the music?

[Carrtoon]

Haha! Just trying WMM out. Wish I had this for SPANO...

[Ronster]

Are you putting the darts in the clip backwards?

[Carrtoon]

Nope. Those are my Flintstone darts. I trim down the back of the dart to prevent jamming. Oh, and they shoot 100' further because they have no drag . Sarcasm *cough*

[Ronster]

How do the darts not jam?
I can understand with brass, 'cause the brass is so thin that it just slips between the darts...
But CPVC is thicker then that...

[elf avec gun]

Did you use something as a guide to make your lines that thick and if so what?

[Ronster]

Did you use something as a guide to make your lines that thick and if so what?

Are you asking about my picture?

[General Cole]

Sweet, I have been thinking on making a clip for my X-bow, only like a EE clip (kind of). I might be able to do this because that is the only kind of barrelling that I have here. Here is what it will look like-

Edited by General Cole, 05 September 2006 - 09:40 PM.

[SG Pilot]

Must say that your breech plus Forsaken_Angel's Angel Bow inspired me to make a breech myself. How did you get the male and female parts to fit together real nicely? I mean how did you cut the peices?

[elf avec gun]

Did you use something as a guide to make your lines that thick and if so what?

Are you asking about my picture?

No. Actually I was asking Carrtoon. Sorry 'bout that one.

[General Cole]

Now, megas or micros, and could you put up data on exact ODs and IDs? Clip dimensions and such. I would also reccommend having less dead space between the end of the plunger tube and where the dart contacts. Oh also, can I buy one of those drill bit casings that you used in you Ls Carrtoon?