Tuning FX Dreamline Classic. Prob a dumb question?

[Trucker3573]

I have been really looking into these with great interest. I’m confused about something. My understanding is that this gun is very modular?? I could order a 30 cal then a 22 cal barrel and bolt probe kit and switch the 30 to 22?? What I don’t understand is that in 30 cal it will do 75 ft/lb. Why wouldn’t it be capable of that much energy or force in 22? Please correct me or help me understand ?

 

[bamavet55]

I have been really looking into these with great interest. I’m confused about something. My understanding is that this gun is very modular?? I could order a 30 cal then a 22 cal barrel and bolt probe kit and switch the 30 to 22?? What I don’t understand is that in 30 cal it will do 75 ft/lb. Why wouldn’t it be capable of that much energy or force in 22? Please correct me or help me understand ?

As to the modularity of FX's Impact etc. the larger transfer ports and bores in larger calibers allow for more air to propel the projectile. Also, on these modular rifles there is the regulator, hammer spring and valve adjustments that allow the user to tune for greater power.

That is my simplistic understanding of the caliber-change capability.

 

[Trucker3573]

I have been really looking into these with great interest. I’m confused about something. My understanding is that this gun is very modular?? I could order a 30 cal then a 22 cal barrel and bolt probe kit and switch the 30 to 22?? What I don’t understand is that in 30 cal it will do 75 ft/lb. Why wouldn’t it be capable of that much energy or force in 22? Please correct me or help me understand ?

As to the modularity of FX's Impact etc. the larger transfer ports and bores in larger calibers allow for more air to propel the projectile. Also, on these modular rifles there is the regulator, hammer spring and valve adjustments that allow the user to tune for greater power.

That is my simplistic understanding of the caliber-change capability.

Right but I not long ago was watching the air tac hunting channel on YouTube and Rolfe was using the dreamline classic in 22. With it completely maxed out it was shooting 23 gr javelins at 830 fps. Seems like it would be capable of more. I must be missing something in my thought process. Maybe if I order a 30 cal it isn’t as simple as changing the liner, probe, adjusting transfer port and turning down reg and hammer spring to convert to 22. It’s confusing. Is it in fact possible to drop from a 30 cal to a 22 using the same gun in the classic platform??

 

[NYmike]

It probably is capable, the problem is FPE depends on how much lead and how fast it's going. To get upwards of 70fpe with a 22 you have to drive the average weight pellets into the transonic zone which destroys accuracy. Even talking slugs you have to get the heavy ones going over 1000fps to approach 75fpe.

 

[elh0102]

Exactly. It would probably require a different hammer/spring, and the velocity would be way above optimum for accuracy.

 

[NYmike]

To continue thinking out loud... It seems to me that there has to be a practical range of FPE for each calliber of airgun due to the driving force we work with, namely compressed air in the 3 to 4.5k psi upper limit. It's simply easier on the machinery and more efficient with the air to drive larger caliber projectiles to slower velocities to achieve high FPE.

 

[FLgunner]

FPE is the result of weight and velocity and drag. A 25 grain .22 cal pellet weighs about half what a 50 grain .30 cal pellet weighs and will have less drag due to a smaller surface area. Due to the extra weight and drag, the air gun with not be able to push the .30 cal pellet as fast as the .22 cal pellet without some modifications/tuning to the rifle, but the addeed wight of the pellet will increase the foot pounds of energy produced. For example, my Dreamline Classic will produce 47 FPE shooting .22 cal 25.39 grain JSBs at an average of 917 FPS. I don't have a .30 cal barrel, but I do have a .25 cal barrel and it will shoot the .25 cal 33.95 grain JSBs at 880 FPS, producing around 58 FPE with no change to the regulator pressure or hammer spring tension. So, If you could get it shooting a 50 grain pellet at around 800 FPS, it would produce 70 FPE. Bumping that to 825 FPS would get you at the 75 FPE you are looking for.

 

[Solo1]

my maverick sniper 22 with a 25 cal hammer will push a 27.5 gr nsa slug to 60 fpe if i change it to 30 cal with all the same settings it will push a 47 gr nsa slug to 100 fpe. i don’t know for sure as i don’t have a dreamline but i think you could have similar results just not as high because the maverick makes more power overall than the dreamline

 

[JimD]

It will always be easier to get more fpe out of a larger caliber. When the hammer hits the valve a burst of high pressure air is released. That air pushes on the projectile as it expands. The force that it creates is a function of the volume and pressure of the air but also on the cross sectional area of the base of the projectile. A 30 caliber projectile has a larger base than a 22 caliber (the math is radius squared times times Pi). A 30 caliber barrel can also have a wider barrel port allowing more air to enter the barrel with less loss.

I have now owned a FX but I wish they made a model more friendly to those of us who shoot from the left shoulder. I think their transfer ports are fixed in size but interchangeable. That is the only additional part you might need or want to change with a large caliber change. The transfer port should be fairly consistent with the barrel port so you probably want a bigger one with a 30 caliber.

I watched a video yesterday where they had an Impact in 22 caliber up around 100 ft. lbs. It used a 800mm barrel, titanium hammer, and other parts a dreamline would not have. I found it interesting that it could be done but it did not make me want to do it. I shoot pellets from my PCPs and I think 50 yards is a really long shot. 25 fpe in a 22 seems about right to me. I have one of my 25s at about 32 fpe because it likes a really light pellet (FTTs) and that energy is what I get driving it 850-875 fps. If you set your guns up to drive your guns favorite projectile 850 fps or so, you will naturally have more energy in the larger calibers because their projectiles weigh more (but there is obviously overlap between 22s and 25s).

 

[177er]

You could get a Dreamline Power Pup - that makes nearly as much power as you want (different internals compared to the regular Dreamline). It still won't go to Impact levels, especially the new M3 setups with 800mm barrels.
But, you can easily switch between 30/22 with the power pup.

 

[elh0102]

I'll venture to answer the unasked question, how do I have the most fun with this rifle? Buy it in either .177 or .22, and enjoy it as designed, at 18 or 30 fpe, respectively. If you want high power, get a HP rifle. You'll be happier.

 

[Trucker3573]

I'll venture to answer the unasked question, how do I have the most fun with this rifle? Buy it in either .177 or .22, and enjoy it as designed, at 18 or 30 fpe, respectively. If you want high power, get a HP rifle. You'll be happier.

This really makes a lot of sense. If I’m chasing high power this probably in reality isn’t the right platform. Thank you much. 

 

[Scouty]

To go along with what Jim D said, I have run quick tests with my Leshiy Classics where I kept barrel length & projectile weight the same (25.39 grains) & only measured speed/power increases when switching caliber.

Whether using a full sized or the smaller sub-12 plenum, 25 cal always has about a 20% increase in power over 22. For what it is worth since it's a different gun.

One of these days I plan to make the same comparison with 177, 22 & 25 using the 16 grain weights in all three calibers. Assuming I have any 16 grain 177's in a sample pack or something.