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awesomedick · Member

Hello Everyone:

I just finished installing a gas spring which I got from Scopes and Ammo into a Crosman Phantom. I am assuming it is the 1100 fps unit from the Crosman range. I can tell you it is a signifigant improvement from the original arrangement.

I would like to try a smiliar upgrade to another Crosman Phantom and was wondering if the gas spring from a Benjamin Sheridan Trail NP XL 1500 would fit.? I have a small lathe so I can modify or make new parts for it if necessary.

I looked these units up on the internet and they look similiar; close enough that I thought they may have the same dimensions.

Thanks,
Rick

SMP · Silver Status Member

It may fit but if your trying to push the velocity past what the OE gas ram will give you then your up against the wall.

The phantom and all other B18/19 varients are limited by the compressed volume of the tube. There is a lot more work potential in the ram than is being utilised

You can achieve about 730fps with a .22 phantom using 14.3gr and thats about it.

awesomedick · Member

Hi:

Thanks, for the reply, I knew that there had to be an upper limit on these guns. The physical size of the compression tube!

So is the physical size of the Benjamin gas spring any different than the Crosman? If not, I do not understand where the extra work potential comes from. I guess I should explain that the gas spring from Scopes and Ammo came with a different piston and back spring guide.

Rick

SMP · Silver Status Member

I assume your asking where does the extra work potential come from comparing the 1100 series and the 1500 series

I'm not entirely sure as I've never seen a 1500 tube but I assume it's bigger. It's a different PN at least.

AirGunEric · Site Admin

There are two "families" of the NPSS rifles- the Benjamin Trail NP's and the Crosman Nitro, and then the Benjamin Trail NP XL/Remington NPSS (and the now discontinued Crosman NPSS).

The Trail NP's/Dusk's are the lower-powered guns- and use the Phantom/Quest/B18-19 platform.

The NP XL's, Remington's and older Crosmans use a much larger tube- which is based on the older, now discontinued Super Streak platform.

The strut for the NP's is shorter (the rod and the strut tube housing) than the NP XL's... It might physically fit in the B18-19 tube, but as was mentioned, it won't make one bit of difference- the limiting factor is the amount of air the tube can compress/move- not how much "spring" (or strut in this case) is behind it. Many many many people chose in the past not to listen, spent alot of time trying, and just could not get past the basic physics at work- i.e. they hit a brick wall and wasted alot of effort, despite good advice.

awesomedick · Member

Hi Eric:

That's what I wanted to hear, the reasons it will not work. I do listen, will pay attention and believe that this mod will not work.

Anyway Eric, the gas spring and the .177 barrel I purchased from you and installed in the Crosman Phantom worked a treat. What an incredible difference in shooting. Smooth, no spring oscillation and no double recoil. Makes a nice noise as well. I had a little trouble at first getting it to shoot tight groups, so I manufactured some extra large in diameter washers out of brass to replace the delrin ones at the break point. That made a great difference.

I will be purchasing another gas spring soon to upgrade another .22 Phantom and see how that will work.

Thanks for your information,
Rick