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jdi73186 · Member

I'm new here and to the airgun world so excuse the stupid questions please.

The squirrels have been destroying the wood on my house (and my neighbors) and getting into the walls. I was talking to my girlfriend about buying a pellet rifle to thin their numbers out some and yesterday to my surprise she informs me she has ordered me a Benjamin Marauder .22 to have some fun with. She didn't order a pump and I'm not wanting to get a pump either. I know I can fill the gun with compressed air but how would I go about doing that?

I know I can use a scuba tank with the correct adapters but since I live in Memphis there's not really a dive shop around here to fill it. And I'm not sure what adapters I'm needing. Could someone help me out and give me some links or something so I know exactly what I'm looking for. And how much would something like this cost?

Ordering a scuba tank and having it shipped isn't a big deal but where could I get it filled with compressed air and what kind of tank should I get? My grandfather and uncle both have their own weatherproofing and construction companies so does anyone think they might have a compressor that would be able to fill a scuba tank?

Thanks!

Teryx · Veteran Member

If you want to use a scuba tank but don't have a dive shop, ask the local fire dept where they fill their SCBA tanks. The SCBAa are filled to 4500 PSI and scuba tanks take 2500, 3000, or 3500 depending on the type you get. You can also get a SCBA tank and do the 4500 thing. There are some real good deals right now on SCBA stuff.

Does your girl friend have a sister ??? Laughing

jdi73186 · Member

Teryx, what's the difference between a SCBAa and a scuba tank other than the filling psi? And is there any price difference?

No sister, sorry bud. She's my little country girl! She rides ATVs, dirtbikes, goes hunting using both crossbows and rifles, prefers a nice 4x4 over a car, and will use that 4x4 to go muddin... She's a handful

AirGunEric · Site Admin

Forget 'SCBA' vs. 'SCUBA'- the only things to be concerned about is the fill pressure- 3000psi vs. 4500psi. You will get more fill-ups from a tank at 4500psi (of the same volume) vs. a 3000psi unit- but it is alot easier/more common to find places able to fill to 3000psi.

Regular shop compressors will not be able to do more than 150psi or so, a specialized multi-stage unit is used for breathing-type tanks.

Another possibility is to use nitrogen from an industrial supplier (i.e. in a welding-type tank) with the correct adapters- it's more expensive but won't hurt the gun.

Teryx · Veteran Member

SCBA type tanks are carbon fiber. The advantages are that they are rated to 4500psi, and they are about 1/4 the weight of a scuba tank. The dissadvantage is higher initial cost and a limited (15 year) lifespan. As Eric said, you get many more fills from the higher pressure tank, and you also are able to fully fill a 3000psi gun if you wish. Both types of tanks require hydro pressure testing every 5 years. The scuba tanks can be used indefinitely as long as they pass hydro.

SCBA type tanks and Scuba tanks are designed for entirely different purposes. SCBA type tanks are designed to be light so a fireman can run up stairs with them. Scuba tanks are designed to be heavy so that they are close to zero bouyancy and require less belt lead. If you cut through an aluminum scuba tank you will see that the wall thickness is about 1/2". You definitely want to steer away from some of the steel scuba tanks that are only rated 2500 psi. Stick with 3000 as a minimum. As far as I know, all the aluminum tanks are 3000, but I'm still learning about this stuff so don't take my word for it.

Before you buy a 4500psi setup, make sure you have a place to fill it. Most dive shops don't go over 3500. The fire dept has to get theirs filled somewhere, so you could always check with them.

DAMN! Well, if you ever decide to dump that girlfriend, give her my number! Laughing

Teryx

sniper · Silver Status Member

i bought a used 80 ci 3000psi steel tank for my mrod and get over 1500 shots on one tank fill filling at 2200 psi.

the "out of the box" power is fine on squirrel out to 75 yards. Shocked

jdi73186 · Member

Well it turns out that Memphis does have a dive shop... Who would have thought?!
Would they be able to fill a 4500psi tank? And if so, would something like this work? Or should I just try and find a 3500psi tank?

And what adapters would I need?

Going to the girlfriends now and she said it came in this morning!

rsterne · Moderator

An 88 cu.in. tank filled to 4500 psi (310 Bar) contains 88 x 310 / 1728 = 15.8 cu.ft. of air.... that's a LOT smaller than an SCBA tank like the firemen use.... Here is a fill calculator:

http://www.airhog.com/tank.htm

Assuming your Marauder holds about 200cc of air, and you fill it to 2500 psi and refill from 1500 psi, you will get about 15 fills from that tank, assuming it was filled right to 4500 psi.... If you fill the gun to 3000 psi, you will only get 7 fills....

Just as a comparison, an 80 cu.ft. SCUBA tank, filled to 3000 psi would fill the exact same gun 28 times.... If you decide to fill the Marauder to 3000 psi, however, it won't even do it once.... Rolling Eyes

Like you were told above.... most dive shops can't fill to 4500 psi.... pick up the phone and call them.... Mr. Green

Bob

Teryx · Veteran Member

rsterne is right. That's about enough air for a fireman to make the sign of the cross and kiss his a$$ goodbye Shocked

You want Cu Ft not Cu In. I'm talking about this type tank:

http://www.hamcontact.com/airgun/HoseAssembly/

Use the calculator that rsterne gave you and play out some scenarios. The Mrod comes set up for 2500psi fills. IMO there isn't much need to go above that with a stock gun. I would only go higher on a regulated upgrade. I recently bought 2 66 cu ft SCBA tanks for $185 with 7 years 8 months remaining. Once they expire I'll buy N2 and fill them myself to maybe 3500. I really like the light weight, and the higher the pressure, the greater the number of fills. Around here a new 88 cu ft 3000 psi scuba tank is $170 and fills are $5.

Teryx

sniper · Silver Status Member

we're all on the same page here. i pay $6.50 for a fill.

if the mrod is your first airgun get ready to be BLOWN AWAY!! Shocked

it is worthy of a good scope. i have a BSA 4-16x40 AO alluminated- mil-dot on mine.
i can nail 12ga shells at 60 yards no problem with a cross breeze. Shocked

enjoy!

sniper · Silver Status Member

and... if she's buying you an mrod and you're not even shacking yet....

save for the ring!!!! Laughing

mine (wife) has bought me a springer for my b-day once. Laughing

sounds like a keeper. Laughing

jdi73186 · Member

Thanks rsterne, Teryx, and sniper. It makes more sense now. On the drive to my girls house I was wondering about whether y'all meant cubic feet or inches. I'll look around and see about getting a 3500psi tank.

It was too late for me to call them after I left work or I would have. Then I'm off tomorrow and Friday for Christmas so I figured I'd just ask y'all.

And sniper, we've already got a ring picked out, just waiting for the right time!

sniper · Silver Status Member

jdi73186 · Member

Sniper, that's why I wanted to go ahead and pick one out or find out what she likes so when I want I can go get it quick and easy without her knowing!

I'm stoked about getting it. Can't wait till I can
use it.

jdi73186 · Member

Interesting...

My girl gave me the Marauder last night and then this morning about 2 hours ago she calls me and tells me that UPS has dropped off yet another package. I ask her what's so unusual about that and she tells me that when she opened it she was surprised to see yet another Benjamin Marauder .22 box! She thought she ordered it twice and was charged twice at first but upon closer inspection of the papers they both had the same order number on them, just different UPS tracking numbers. Apparently whoever she bought them from thought it would be nice to send me 2 Marauders for the price of 1!

Now I just need a scuba tank, a scope, and some time to play with it while getting the scope zeroed in! And some non-rainy days would be nice!