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GoodEnough · Member

Hello folks Smile

There has been a big noise over the past 2/3 of yrs about NP's
I want to know what the "exptected" life cycle is - of a Nitrogen piston Airgun. Also would like to know what issues NP users have had so far (not Trigger related issues or scope issues) probs specifically with the NP powerplant.
What are the pro's / cons of springer vs NP ?

I suspect there probably will be supporters of each type & then some other type as well (PCP for eg.) but I just want to have a head to head real life count of actual user issue comparison just between these 2 platrorms (regardless of calibre)
Looking forward to the posts as it will not only help me, but others as well - to gain general know how between platforms & to perhaps make a better informed decision on a purchase.
Heard "rumors" that NP has/develops issues: or that the tech inherently is not as reliable as springers (based on what they never seem to say) I have not seen too many of these NP users that are supposed to have issues - on any forums .. actively discussing issues .. (tech is too new perhaps ?) or is this maybe a ploy by manufacturers that are saying springers are more reliable .. so they have enough time to switch all their production formats to change over to NP ? who knows ? all conjecture ? .. so pls post away ! I mainly need to know Spring vs Np & the longevity of said powerplants.

Chat soon y'all

Chat soon Smile

)

SMP · Silver Status Member

Well I have two identical crosmans one has a full power (PAL Rated) spring and the other has the full power NP. These are the differences I notice

The lock time (time from trigger pull to bang) is much faster with the NP

The recoil of the NP is straight back and quite vigorous. The springer rotates a little and has less rear recoil.

There is less mechanical noise from the NP but the muzzle blast is louder

Peak FPS is identical

The NP is a little less hold sensitive and prefers to be pulled hard into the shoulder ( Please be aware that the latter is totally a preference of THIS rifle and may not apply to anything else)

As for longevity

Both are doing fine. The NP has 30,000 shots thru it and I'm expecting that its gotta be close to it's life cycle. I have looked after the ram by putting a drop of extra fine machine oil on it periodically....I have no idea if this has made a difference. Only one drop right one the steel ram...keep the machine oil away from the piston Laughing

Subjectively yes the rams do eventually wear out and start loosing gas but springs also wear out and break. I think it's 6 of one and a half dozen of the other really.

GoodEnough · Member

Thanks for sharing Sean, what is cheaper to replace .. springer innards or NP. Also the "shroud" on the NP .. isn't a shroud supposed to have baffles on the inside & over time baffles (& silencers) need to be cleaned .. how would one go about cleaning these new shrouds - or is this some other kind of shroud ... maybe "just another tube" around the barrel ?
I'm sure it still muffles SOME sound but is it a "proper" shroud (with baffels/blowback etc.)
Maybe it is a new kind of no cleaning required tech ? .. like non stick pan (those I personally find amusing - cause they always have a sticker in the middle saying "Non-stick")

Lubing me Benji now .. & speaking of longevity is there a stock trigger adjustment/deburring etc that anyone knows of .. ?
If the topic is too different I can start a new one.

biab

rsterne · Moderator

A general comment about cold weather might be in order....

Steel springs, in theory, don't change to any significant degree with temperature.... so the power should be a constant.... IF the spring is coated wth any kind of "tar", however, the thickening of the tar and loss of velocity when it is cold could be quite dramatic.... (one reason I hate tar)....

NPs, since they are full of compressed gas.... have a pressure change in proportion to the absolute temperature (Kelvin or Rankine).... If you have an NP that produces a given force at 75*F (535*R) then at 0*F (460*R) it would only have 460/535 = 86% of the force available.... That wouldn't likely mean a 14% drop in velocity, but it would be noticiable....

Both types would also be susceptible to losses related to lubrication on the piston thickening in cold weather as well.... but that would be the same for both types of "spring", steel or gas....

Bob

SMP · Silver Status Member

rsterne · Moderator

So what you're saying is that the gun is so "oversprung" that the last 14% (or more) isn't doing anything to the velocity.... Rolling Eyes

Interesting, and entirely possible.... BTW, I have a Red N-Forcer 19x100 mm Ram sitting here awaiting installation in a Phantom.... when I can get around to buying one as a test bed....

Bob

GoodEnough · Member

Well - I fixed the stock trig already on my Classic .22
Anyone have info about what kind of shroud the NP XL1100 has & if the barrel is choked ?

Thanks fellas.

Pete

SMP · Silver Status Member

Here is a simple way to describe the shroud on all the crosman NP's and springers

Take a 6" long bolt and place a washer on it

Slide a 5 1/2 long pipe over the bolt

Place another washer on top and tighten a nut down on it.

Thats it. There is no porting on the inside that would actually attenuate the muzzle blast. The only thing the shroud could possibly do is attenuate the harmonics coming through the steel wall of the barrel

Edit: AFAIK there are no crosman barrels with chokes. The only rifles and pistols that crosman has that are choked use Lothar Walther barrels or possibly Green Mountain. But there is nothing to stop you from choking it yourself.

GoodEnough · Member

Hi Sean & ty for your input much appreciated Smile

I had been thinking of doing it myself. Have you any experience doing it & if so I would love to know the results, also any recommendations on a particular method ?
I did see a LW barrel for sale on scopes&mmo http://scopesandammo.com/storefront/product_info.php/crosman-lothar-walther-177-caliber-101-barrel-target-p-505

Wonder what they mean by "can be used on any of the 13xx, 17xx, 22xx guns"
22xx does that include the NP XL1100 I wonder..any insight on that ?
There are choked barrels that can be ordered from LW http://www.lothar-walther.de/457.php - course in such a case one would have to give up the "shroud" or find a way to fit the new barrel with one.
Now what i am really interested in is - has anyone tried to fit an NP XL with one of these barrels .. I know the XL is fairly new on the market & probably does not have as many mods that people have done yet but what do people here think about this idea ?
Course I am not discounting a diy barrel choke on existing barrel but that remains to be seen ... any one that has done this can you please offer input ?

pls note : I currently have the BS classic .22 but am looking into getting the NP XL1100. (would love to choke stock barrel on the classic if chances of runing it are low)

Thanks people Smile

thepaladin · Senior Member

Actually nitrogen is used because it's an inert gas and doesn't react greatly to temperature variations. We used it in Air Conditioning and refrigeration applications to test systems for that reason. That's (as noted) why it was chosen for this use. I always wondered if it would be practical as a power source?

SMP · Silver Status Member

GoodEnough · Member

Sean ty for that info .. what tut is best ?

SMP · Silver Status Member

GoodEnough · Member

Sorry about that Tutorial (aka 'tut' in some places for abbreviation)
also makes me wonder why abbreviation is not a shorter word.
Where may one find a good tutorial on how to free choke a barrel.
Tried doing a search on "free choke" & some other variable words
didn't get much in results although there are numerous on google/utube etc. If there are any or one you know that is best .. pls direct me to one ..?

Thanks a bunch.

SMP · Silver Status Member

As I said I need to know if the barrel is tight or loose in order to send you in the right direction