EDIT: Leaky probe on .30 cal EDgun – The FIX is HERE!
Hi guys. Anyone have a few of 5.5mm x 1.5 buna 70 that you can send me?
I’ll pay all the costs. I need them pretty bad and oring store is out of stock.
Peter
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SECoda, the -008 O rings are actually .070” CS and not 1/16” (.0625). Any O ring larger than a -003, while still called 1/16, is actually .070” CS.
The spare O rings that Ed includes in the package of spare O rings are still working for me. F&D is sending me a couple of the 5.1 X 1.6 mm O rings for me to try.
I did some conversions for some commonly available Metric O rings.
5.0 X 1.5 mm = .196” ID X .314” OD .059” CS
5.1 X 1.6 mm = .200” ID X .327” OD .062” CS
5.5 X 1.5 mm = .216” ID X .334” OD .059” CS
McMaster Carr has these 90 Duro Buna N SAE O rings for sale cheap and one of them might work.
5308T117 is a SAE-008 standard size and measures
.176” ID X .316” OD .070” CS
5308T118 is a SAE -009 standard size and measures
.208” ID X .348” OD .070” CS
Each of them are $2.32 for 100 + shipping.
When one of us comes up with an O ring size that seals and lasts, I will place an order with Sealing Specialties for 500 of them in 90 Duro Buna N and send a bunch to each of us 30 cal owners.
I FINALLY fixed the probe noise/leak but don’t laugh. My last O-ring order from the Oring Store didn’t arrive yet so for grins I stuck in two SAE orings lubed them up with Molykote 55 that is from a cheap oring kit and voila. 😯 I don’t know how it will wear over time but it works great for now and I have a bunch of them. It is just a common AS-008 (R-02) (corrected). 1/16″ thick which converts to 1.58mm.
Try the tissue test on these. 😉
No ear plug needed. :8: :8: :8: Let us know if you try it.
I got a few minutes to play this afternoon. Based on a tissue test, it looks like the air is still coming past the probe. I guess it’s time to try another different o-ring.
While I had it out, I shot a few over the chrony. Without any adjustments, it is shooting 790-800fps, SD around 3. And it looks like it comes off the regulator around 160-170bar, and then the velocity starts to climb. I want to get the probe sealed, but then it will be time to tighten the HSP a bit and maybe move the velocity a bit higher.
But I can’t fault how it shoots – at 50 yards, I have to change aim points every 5 shots or so to see where I’m hitting, because the pellets are just going the same hole. 🙂
Those should be here next week or possibly tomorrow.
Its cured! Completely!
I just got a package of 5.1×1.6mm Duro 50 O-rings. Installed them in my .30 Long and blow by is completely gone and sound is back to normal where I dont have to use ear protection to shoot it. (5.5×1.5 helped a little over the original 5×1.5, but it still leaked a little)
The brand new .30 Standard that I have (Its for sale) also had small probe leak and new 5.1×1.6 rings completely cured that too!
Nope, bolt is locked down. I’ll see if I can figure out exactly where the air is coming out, but it might be a few days as my tinkering time is limited right now.
YES!
Its cured! Completely!
I just got a package of 5.1×1.6mm Duro 50 O-rings. Installed them in my .30 Long and blow by is completely gone and sound is back to normal where I dont have to use ear protection to shoot it. (5.5×1.5 helped a little over the original 5×1.5, but it still leaked a little)
The brand new .30 Standard that I have (Its for sale) also had small probe leak and new 5.1×1.6 rings completely cured that too!
Is it possible you are getting “blow back” from the bolt coming back a fraction from the .30 caliber’s significant air pressure pushing against it?
Try holding the bolt down tight when firing, and see if that stops the residual puff of air you are getting.
Kindest regards,
Uncle H 😯 😯 t
PS: For a temporary fix: you can use some parachute cord, and tie a brick to the knob of the bolt and simply let it hand down when shooting.
I just put a pair of the 5.1×1.6 o-rings on my probe. It’s definitely better than the 5×1.5, and I think better than the original o-rings. The probe definitely feels like it is sealing in the breach now. However, I am still getting a puff of air and extra noise in the right ear when shooting. The screws to the front breech block are tight; I did not check to see what is in the transfer probe. Hmmm . . . .
I used Viton’s for the fuel grommets on my airplane. 😀
Any thoughts on Buna N v. Viton? IIRC from my younger days, the Viton is better for exposure to hydrocarbons, but I’m not sure remeber much else that’s different.
Yeah, I ordered several different versions that seemed like they were in the right range.
Any thoughts on Buna N v. Viton? IIRC from my younger days, the Viton is better for exposure to hydrocarbons, but I’m not sure remeber much else that’s different.
I have some coming of every possible size including those for .040 each. 😯
Awesome! I have a very good feeling that they will work.
I have some of those on the way, I’ll let you know if they work for me.
I think this ring right here might be an answer to our troubles. (so damn expensive though)
5.1×1.6
http://www.theoringstore.com/index.php?main_page=product_info&cPath=368_12_40&products_id=18376
EDIT
Here is a quick breakdown.
5.0×1.5mm is 8mm OD
5.1×1.6mm is 8.3mm OD
5.5×1.5mm is 8.5mm OD
I really think the 5.1×1.6mm is the ultimate fix for this leaky probe issue.
I ordered 50pc from the link below. I ordered from them before. Fast shipping.
found them on EBAY
http://www.ebay.com/itm/200767974297?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
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.30 cal matador probe update.
Tedd sent me a few probe O rings 1.5mm x 5.0mm. my first attempt, it failed the tissue test. I removed the probe and found that I may have nicked the O rings either due to poor installation or not enought lubricant. The second attempt, I used good amount do Shin-Etsu grease (fancy Japanese silicone grease, same as Dow Corning 55) and found the air leak is gone. Although the air is no longer leak, I still have doubt that it will last for a long time because the probe that rotate up/ down does not have much resistance. If you are careless when shooting, you can accidentally knocked the bolt into the up position(happened to me), you can have a heart attack!!!!
I got some 1.5mm x 5.5mm to try, it fit loose because the inside diameter is slightly too big. Seemed like it is hard to close the bolt and it does not evenly sealed the probe area. It is very hard to close, if it closes at all.
My last attempt was the 1.6mm x 5.1mm. I used the same silicone grease inside the grooves, rolled the Orings into the probe and worked the Orings into the grooves evenly. I applied light grease to the breech area with a Q-tip. My first couple if tries, I applied pressure and rotate the prove to give it even pressure on the O rings. It worked great, no more leak and I really liked the resistance the O rings give against the breech. The bolt now has plenty of resistance and I think it will last the longest compared to the other O Rings.
I have a few, if you guys wants to try, PM me your address, I will send you some. No charge, of course. I hope we can all agreed the 1.6mm x 5.1 mm is the fix for this pesky probe leak?.
Johnp