I was fixing a customer's Discovery and....July 2 2009 at 12:04 PM
Mike T. (Login TKO22)
He lives in the Southern part of the USA and only has a pump. He also shoots a lot!
First time I have seen that mush rust in a Discovery.
Does this mean I absolutely need to get a tank?
|July 2 2009, 1:03 PM |
I live in Durham, NC. I am planning to get my first PCP(only CO2's so far)and I shoot about 50-60 pellets per day(2 hours every day)and sometimes even more, which means if I get a PCP, I have to pretty much fill my gun every day, and often more than once. Does that mean I can't get by with a handpump and should get a tank? I was planning on a handpump because it's cheaper-- but at the same time I wouldn't want to ruin an expensive gun with rust. Anyone in NC have any suggestions from your own experience?
There was no other rust in or on the gun...
|July 2 2009, 1:08 PM |
nothing in the valve, gauge fittings, barrel, etc.
There must have been something in the end of the airtube that attracted moisture. The fill adapter is stainlesss steel and it self wasn't rusted... just some rust fuzz growing on it as seen in the picture.
I guess my theory is "most" folks eventually get a scuba/scba tank if they shoot alot.
|M in NC|
Re: Does this mean I absolutely need to get a tank?
|July 2 2009, 4:06 PM |
Roy, for what it's worth, I also live in Durham and haven't had any trouble with my Discovery. Of course, the gun is inside most of the time in air-conditioned comfort, and it's been breathing scuba tank air after the first month with the pump. Judging by the amount of shooting you do, you're either going to get into terrific shape hand-pumping a PCP, or you'll also soon move to a tank.
If you're interested in the aforementioned Disco, send me a note at email@example.com. I just bought a Marauder for the extra quiet and the repeating action, so the Disco will be sitting idle. Which is sort of a shame.
Re: Does this mean I absolutely need to get a tank?
|July 18 2009, 9:27 PM |
Hey Mike,what cal is your Disco and is it up for sale/What mods have been done to it?If for sale ,Im interested!
Very good post
|July 2 2009, 1:05 PM |
I definetly will have to go the nitrogen route. I can get a 6000psi tank for 80 dollars down, and 80 a year lease. Looking seriously into this. Especially after this photo.
|July 2 2009, 6:00 PM |
Mike those pix scared the cr#p out of me. I got one of the first Disco22's, #34 and I've been using the Benji pump since the beginning. Lots and lots of fills and it's been very damp on Long Island. I just ran downstairs, degassed and opened the Disco. WHEW! not a speck of rust, tube is clean and shiny inside.
Thanks for a great post and an important wake up call. It only takes a few minutes to check the tube. I feel much better now.
Now, how do you remove the fill adapter from the Marauder? I'd like to check her too.
Re: Great post!
|July 2 2009, 7:29 PM |
On the marauder you can remove the front barrel band, then put it back onto the fill adapter with the barrel band facing down not through the barrel and tighten the set screws. This will allow you to loosen the fill adapter, then remove barrel band and hand loosen.
|This message has been edited by tjb59 on Jul 2, 2009 7:33 PM|
Re: Great post!
|July 3 2009, 4:53 PM |
Thanks for the info Tim, I'll give it a try.
Re: I was fixing a customer's Discovery and....
|July 2 2009, 9:10 PM |
Open them up and take a look. Am a tinker at heart, and have had every PCP open at one time or another (and most of them several times), Haven't found rust, and at least one of the guns has been in use with a pump for several years down here in high humidty land (Southern Louisiana). Can certainly see how it can happen, and perhaps it will happen sooner or later to me, but I'll keep on hand pumping.
In fact, if I read the Discovery manual correctly, the only two ways that they give the "ok" for filling a Disco are (1) pump and (2) discovery regulated fill tank.
Great post and pics Mike!
|July 3 2009, 2:50 AM |
Thanks for sharing!
I really don't think humidity matters.....
|July 3 2009, 6:28 AM |
I mean think about it, shop air compressors collect liquid water. Even in the desert. The physics of it is at any given temperature the air (no matter how dense or what pressure) can only hold so much water. At normal pressure (like where we live) this number is something like a few percent of the total. Any more than that and you have fog, clouds, dew, rain and all that stuff. Double that pressure (to say 1500 mm of Mercury), two atmospheres, 15 psig, and you have twice the problem (you can still only 'hold' a small weight of water in a given volume tube). Go to 150 psi and the problem is ten times worse. Pump your Discovery to 100 atmospheres (1500 psi) and unless your relative humidity was under one percent (in which case you're probably dead) you'll have condensation in there.
Rust on surfaces at normal pressure is another matter of course. Local humidity counts big time.
I think Tim's right. Unless stuff is 'rust proof', or otherwise protected (he recommends a thin coat of grease, also traps debris) you could be in for trouble. It's wet in there.
I have a Career Ultra that died from rust due to occasional hand pumping (long storage after a hunting trip). Tim saved it.
I think tank air is a good start, but there is a risk even then. One of the reasons SCUBA tanks are inspected (valve removed and a survey for cracks and rust inside) every year. Some of those tanks see a lot of use in a year. Coating them with grease or anything else a diver could breathe is clearly out of the question. Many years ago makers tried to get around this with glass liners on the inside of SCUBA tanks. It backfired, the rust would work under the liner......
Wow....thats not good
|July 3 2009, 12:30 PM |
|July 3 2009, 12:51 PM |
about a pump filter that PA has on their site was kind of worried about that and at the time everyone that answered said don't worry about it,now I guess I need to start .
News flash!! Tim McMurry is all wet on pumps as sole air source?
|July 3 2009, 2:29 PM |
Chalk another one up to the school of Hard Knocks. I learnt one lesson that way, ignoring Tim's advice, but like your Mamma in the end is always right. I've paid careful attention ever since.
FX is as far as I know the only PCP manufacturer that claims moisture won't hurt their guns(stainless, brass?) and would(according to their claims)be "pump safe".
|This message has been edited by 22MK1 on Jul 3, 2009 2:31 PM|
Go with the guy that's been there?
|July 3 2009, 5:01 PM |
Sounds like good advice. Of course you don't have to listen to what others have learned through there experience if you have enough time and don't mind making the same mistakes.
Funny how FX says it's OK. Maybe their guns are that well protected? I'm sure it has nothing to do with selling those lovely pumps......
Opened up my PCP rifle and found..........
|July 3 2009, 9:06 PM |
No rust! Thank God. I have a Career Infinity that I had to tear down due to seal leaks. Everything inside the air chamber is brass or aluminum. The only thing I found that may get some corrosion are the two plated springs (exhaust valve and fill check valve spring). I don't thing I have to worry about corrosion inside this gun.
What I am concerned about is possible corrosion in my future purchase. I'm very interested in the Maurader in .22cal. Being that the Dico has internal steel parts that will rust, will the Maurader have similar internal steel parts that will also rust ? Has anyone tried coating those parts with some sort or Teflon coating ? Will that help ? Thanks
a few questions.....
|July 10 2009, 2:33 PM |
hey great post! im getting a custom 2250 and its been moddified with a discovery tude to mak eit pcp, would i have to worry about rust? the rest of th egun is stainless steel, i use a hand pump too, but i only shoot my guns maybe 3 times a week at the most, would i have to worry about rust??
|July 11 2009, 12:01 PM |
I took my fill plug out and mine looked ok. Since the plug looks to be nickel plated and the tube is blued steel oxidation between dissimilar metals may be part of the problem. Might not be a bad idea to put a little No-Ox lube on the threads.