Air leak at breech when fired

[fife]

I don't know if anyone has touched on this before (I searched and came up empty). I can't stand the fact that the breech is loose and rattles when closed. I also don't like how much air leaks from the breech everytime you fire. I checked 8 other Speeds and found this on all of them. One thing I noticed is the newer Angels (Speed, A4) use a molded seal in the breech versus an o-ring style like previous models. This seal doesn't even make contact when closed (I checked with waterbased paint). So this weekend I tried the small o-ring that comes in the parts bag. The gun is noticeably quieter, the breech is tight and my velocity immediately went up an average of 15 fps. This week I am going to compare how many more shots I get out of a 68/4500. I guess the theory is better efficiency, more shots?

Any comments??

[firemedic30]

I'm not 100% sure of what you are talking about. My Speed's breech is tight when closed. Is there still a breech rod spring on yours and the others?? As far as air, I don't feel any coming form the breech.

[fife]

Yes the breech rod springs are intact. Because the bolt design doesn't use o-rings, there always is some air that leaks out of the breech when the gun is fired. The amount of air that I'm seeing is excessive in comparison. Greatly reduced when I have the o-ring in.

[pgaglio]

I know that some guys have super glued an O-ring in place to reduce this leakage.

[SunTzu]

i never noticed any leakage of air at the breech but will look out for it now.

where would one put the o-ring if he wishes
do u mean where the opening between breech and valve is because thats air tight with me...

[SPiFF]

Neither have I..

I noticed that you mentioned that the breach is "lose" even when you close it..

Are you sure that you haven't screwed in the breach knob to far? If you have done that the breach rod (in its forward closed position) will not stick out enough to close the rota-breach against the body as tight as it should be..

The sum of this is: The breach know should not be screwed in all the way on the breach rod, just as much so that cut out edge is flush with the backplate, if you know what i mean..

[fife]

I've never unscrewed the breech knob, and I did check it and it is tight. I don't think that would cause this issue anyway. I also just checked a NEW Speed out of the box, same problem.

I will take a pic tonight to elaborate. Suggestions on how to post the pic here???

[Icehawk]

I'm trying out the breech o-ring mod right now so I'll tell ya how it works out when I get the chance to test it. The o-ring that works is a cocker valve o-ring. Also if you do decide to do it make sure you use superglue GEL not regular superglue.

[hooha]

There's such a thing as too tight. If the o-ring you added makes the breech block stick up too high, you'll get extra wear on your bolt because it will rub on the side opposite the o-ring every time you fire. If you notice extra wear on the bolt, I'd say your o-ring is too big. Just something to watch for.

There's a thread on this in the LED forum, and that was the advice I got there. Or maybe it was on pbnation, I don't remember. :notsure:

[firemedic30]

Hey fife, just post a message and then go to (manage attachments) and add the pic.

[Icehawk]

Yeah, the o-ring was a bit too thick so I just took a file to it until the breach cloded without me having to push on it. The seal does seem to be alot tighter and more secure, though.

[fife]

That's a very good point about not using too large of an o-ring. The o-ring I used just happen to be a perfect height or thickness. When I closed the breech, the pin received very easy but there is slight pressure needed to close the breech. (See pics) Notice that the stock seal made a very little imprint on the gun, most of the paint is because I had excess on that side if the seal. If the seal was tight or complete the paint would have shown up around the entire circumference. You can see with the o-ring the I put in how the imprint is complete and the color variations in the paint indicate how tight the air seal is.

I also chronoed last night before and after the o-ring. I use Ken Crane's setup, slightly modified, and without the o-ring velocity varied +/- 10-15 fps on average. With the o-ring <5 fps!

Keep in mind I'm not trying to be-little Angel in any way, and I am die hard Angel and they make some of the best markers. I am trying to figure out a couple minor problems either by design or defect.

KEEP IN MIND THAT THE O-RING WILL REST IN PLACE WHERE SHOWN WITHOUT GLUE. Turn the gun upside down and close the gun onto the breech so it won't fall out. The slight pressure the breech exerts on the o-ring will keep it in place.

[pgaglio]

The o-ring that works is a cocker valve o-ring. Also if you do decide to do it make sure you use superglue GEL not regular superglue.

Do you happen to know what size that is?


Also, thanks for the pics Fife.

[hooha]

Yeah, thanks for the pics. I may give this a shot myself. It's a very reversible mod if anything goes wrong or I don't like how it turns out, and increased consistency is always a good thing.

[screamin4vengeance]

anyone know where i can get a breech seal for an 04 speed. ive searched the web and came up with nothing

[Trigga Nometry]

anyone know where i can get a breech seal for an 04 speed. ive searched the web and came up with nothingFMA has them listed under the Speed replacement parts here:
http://secure.fixmyangel.com/modules.php?name=catalog&file=product_info&cPath=22_20&products_id=258&osCsid=0a9ca0b6da0632d0cb3003b9b0aa2ff1

I would contact BoB here on AOG to make sure it will fit your Speed 04.