Regulated Gamo Urban

[cbourbeau32]

For those who have regulated their Urban. Is it possible to get 2 mags of jsb 18.1's at 825 fps +/- per fill?

Thanks!

[Airnut]

Charlie
That's what I have my non regulated Urban tuned at and just barely get two mags.
Now we have a 105cc tube without a reg. so when you ad the regulator you will have less volume in the tube.
I don't think you will make two mags BUT I am just guessing??

[cbourbeau32]

Charlie
That's what I have my non regulated Urban tuned at and just barely get two mags.
Now we have a 105cc tube without a reg. so when you ad the regulator you will have less volume in the tube.
I don't think you will make two mags BUT I am just guessing??

Thanks! How many turns in from minimum (or out from max) is your hammer spring?

[Ribbonstone]

Always a challenge to get a regulated rifle to shoot to the same power as an unregulated rifle….whole idea of regulation is to create a uniform pressure lower than fill pressure to get a longer(more uniform) shot count.

[festis77]

My Urban has an Altaros regulator in it.  About 8 turns in on the hammer spring gives me around 715 fps (20.5 FPE) with JSB 18.13.  I get right around 33 shots before I see the pellet start to drop off at 35 yards.

[Airnut]

Charlie
That's what I have my non regulated Urban tuned at and just barely get two mags.
Now we have a 105cc tube without a reg. so when you ad the regulator you will have less volume in the tube.
I don't think you will make two mags BUT I am just guessing??

Thanks! How many turns in from minimum (or out from max) is your hammer spring?

Sorry I don't really remember. I should have it in my notes. I will check when I get a chance.
That was easy! According to my notes I am in on the hammer spring 6 turns from the stock setting.

[cbourbeau32]

My Urban has an Altaros regulator in it.  About 8 turns in on the hammer spring gives me around 715 fps (20.5 FPE) with JSB 18.13.  I get right around 33 shots before I see the pellet start to drop off at 35 yards.

Thanks, is that set at max psi for the regulator?

[CraigH]

Since the rifle has a tube with 3365 psi rating, it might be possible, or come close to that result.

My Urban (tuned as desired, and unregulated) will run 780.7 fps average for 38 shots (18.7 ES) with 2750 psi starting pressure going down to 1400 psi.

[cbourbeau32]

Since the rifle has a tube with 3365 psi rating, it might be possible, or come close to that result.

My Urban (tuned as desired, and unregulated) will run 780.7 fps average for 38 shots (18.7 ES) with 2750 psi starting pressure going down to 1400 psi.

Thanks, do you remember what your hammer spring setting was?

[cbourbeau32]

Charlie
That's what I have my non regulated Urban tuned at and just barely get two mags.
Now we have a 105cc tube without a reg. so when you ad the regulator you will have less volume in the tube.
I don't think you will make two mags BUT I am just guessing??

Thanks! How many turns in from minimum (or out from max) is your hammer spring?

Sorry I don't really remember. I should have it in my notes. I will check when I get a chance.
That was easy! According to my notes I am in on the hammer spring 6 turns from the stock setting.

Do recall how many turns in from all the way out (lightest) that is?

[CraigH]

Since the rifle has a tube with 3365 psi rating, it might be possible, or come close to that result.

My Urban (tuned as desired, and unregulated) will run 780.7 fps average for 38 shots (18.7 ES) with 2750 psi starting pressure going down to 1400 psi.

Thanks, do you remember what your hammer spring setting was?

Not precisely.   My rifle was a bit over 850 fps out of the box with about 2950 psi fill.

I had a 750 fps tune by backing out 7 turns (from factory setting).   So probably about 1-2 turns back in for 780 fps - 790 fps I guess.