REGULATED AND NON-REGULATED whats it mean?

[geewhiz380]

i see some pcps that say regulated and non -regulated and for regulated ags they want much more cash  ...please explain ...thank you in advance ...

[rsterne]

An unregulated PCP is one where the pressure at the pellet drops from shot to shot.... You would think that would make each shot slower, but in fact through careful design and adjustment, the shots start off slightly slower, increase in velocity, plateau, then gradually decrease.... By adjusting the gun and the fill and refill pressures you can determine how much velocity variation you have over the string.... 4% is typical for shooting out to 50 yards or so, 3% to 75 yards, and 2% at 100 yards to keep the vertical stringing within an acceptable group size....

A regulated PCP has a regulator between the high pressure part of the reservoir and the pellet, which delivers a constant pressure, and hence a more consistent velocity over the shot string.... A 1% variation would be typical.... However, since the output of the regulator is less than what you could use without it (for example a 3000 psi gun might be regulated down to 1800) you generally will not achieve the same maximum power as you can with an unregulated gun.... There are exceptions, of course, and regulated guns can be designed with that problem in mind and addressed to some degree.... Generally, regulators are better for delivering long, consistent shot strings at low to medium power than for maximum power....

Bob

[Ribbonstone]

Can see the confusion, and I’m likely to make it worse.

REGULATED There is a mechanical device inside the air tube (or on the end of a detachable bottle) that only lets out a certain set pressure.  So the valve side of the PCP only sees one pressure even if the other side of the air tube is filled to 3 or 4X that pressure.  So thought out, the pressure remains constant to the valve.

NON REGULATED: No device, so every shot taps off a bit of air, so the air pressure constantly drops, so the air pressure to the valve constantly drops.


Now to add confusion:

SELF REGULATION:

Over a short pressure range (small number of shots), a non-regulated gun can very consistent.  This is because of a tug-of-war between the striker’s hit to the valve stem and the pressure in the tube holding the valve shut. Have one force (the striker) trying to open the valve and another force (air pressure) keeping it closed.

So when the air pressure is high, the striker can only open the valve for a short little “blip”.  At lower pressure, the striker can open the valve a bit longer, giving a “blap”.  Odd thing is that for a short pressure range, the valve hit and the shutting force kind of blance, and the pellet’s velocity with a “blip” is about the same as with the “blap”.

WHICH is why, with a non-regulated PCP, if you fill it to higher pressure than the striker force, you can either get lower velocity (or no shot at all if the striker can’t open the valve at all).  At  the other end of the tug-of-war, at too low a pressure, the velocity also drops, as there just isn’t enough pressure left to drive the pellet to the same speed.

[grobe1458]

my marauders are not regulated, that first pcp love affair quickly slowed when I acquired two new mistresses, the s510 and bsa mk2.
I plan to regulate the marauder soon.

[Motorhead]

If you shoot a PCP for utmost accuracy, require shot to shot POI for many shots, Don't like to be neurotic on filling to a specific pressure and stop shooting at a specific pressure in order to maintain accuracy .... There is a Regulated gun in your future !!

Own 4 PCP's of which NONE came regulated ... ALL have regulators in them now 

[Ribbonstone]

Kind of a counter point, but  will readily agree that Motorhead is 100% right. If you want a long consistent shot count, regulated guns are the way to go. 

Do run some regulated guns, and it’s great for long strings of consistent shots (often +100 shots). 

It’s a lot more work, and you have to be  strictly attentive to fill pressure, but for some guns, for some uses, am not going to resist regulation.  Know I could get 3X as many shots per fill, but suspect it would take me 3X as much pumping to refill it., so my effort would be the same either way. 

If I were a tank filler, might look at it differently as the “sweat equity” wouldn’t be mine.

Only get 30 shots, but over those 30 shots, doubt a regulator is going to really make much difference on target. (OK. I”cheated” with my best example. Those AAs200’s are awesome):

[geewhiz380]

absolutely there will be a regulated ag in my arsenal for sure  ..i gladly appercciate the feeback and education i got from you gentlemen  ...thanks ..jorge

[1216bandit]

Does one tune regulated and non-regulated guns the same way?

[Chemdawg]

Could someone point me in the direction of where i can get a regulator for my .25 mrod?

[rsterne]

Regulated guns have a "sweet spot" where the velocity peaks.... If you increase the hammer spring preload, that peak moves to higher pressure.... In a regulated gun, changing the preload has a similar effect, as in the graph below....



If you have more hammer strike than you need, the velocity doesn't increase, but the gun wastes air on every shot, this is on the plateau on the left.... If the hammer strike is too light, the velocity drops, as on the right.... Where the plateau and the slope meet is the "knee" of the curve, and IMO the best place to operate a regulated gun.... You will get nearly maximum performance from that pressure at good efficiency.... On that graph, I would run the gun between 4-5 turns out on preload....

Bob

[Chemdawg]

I found two places to get the regulator from. 

http://www.ebay.co.uk/itm/BENJAMIN-MARAUDER-M-Rod-FX-WEBLEY-Regulator-/121238620648?pt=UK_SportingGoods_Hunting_ShootingSports_ET&hash=item1c3a6289e8

and this one:

http://www.altaros.cz/regulators/benjamin-marauder

Which one is the better bet for the .25 marauder...?

[QVTom]

If you shoot a PCP for utmost accuracy, require shot to shot POI for many shots, Don't like to be neurotic on filling to a specific pressure and stop shooting at a specific pressure in order to maintain accuracy .... There is a Regulated gun in your future !!

Own 4 PCP's of which NONE came regulated ... ALL have regulators in them now 

Best case for a regulator I've come across.

The convenience factor hadn't occurred to me.

Tom

[grobe1458]

that altaros unit looks pretty simple to install. I appreciate the links.

[Motorhead]

that altaros unit looks pretty simple to install. I appreciate the links.

Easiest to install .... WORST consistency, Lowest power potential    being a NON-VENTED design & non enough plenum space

Huub ... Audrius ... Dan Brown your better choices In That Order 

[geewhiz380]

Could someone point me in the direction of where i can get a regulator for my .25 mrod?

  yes i have seen them in aoa airguns of arizona .....

[Motorhead]

Could someone point me in the direction of where i can get a regulator for my .25 mrod?

  yes i have seen them in aoa airguns of arizona .....

.25 M-rods are NOT a good candidate for a regulator ... unless you want lower power overall.
The bigger calibers take HUGE mounts of air and a very large plenum ....

[Chemdawg]

Thank you for that Motorhead.  Glad I didn't waste the money. 

[grobe1458]

Could someone point me in the direction of where i can get a regulator for my .25 mrod?

  yes i have seen them in aoa airguns of arizona .....

.25 M-rods are NOT a good candidate for a regulator ... unless you want lower power overall.
The bigger calibers take HUGE mounts of air and a very large plenum ....

thank you for sparing me pain and frustration. I'm researching regulators and came upon rober lane design on youtube which along with you guys information very informative. he mentions a valve standoff did you incorporate that in your AG's? if so how did you determine the length?
I now understand the importance of having the breathing hole.and will look into more of the units you spoken of.

Thanks again.

[Motorhead]

Valve standoff ... not too sure what that refers to ?

We do use spacer sleeves or other means to gain volume between regulator output and valve. ( AKA: Plenum )
Bob came up with a very useful approximation of "Plenum" volume required being a maximum/optimum of 1cc plenum volume per Foot Pound of power your wishing AG to produce.

[rsterne]

I always strive for 1 cc of plenum volume for every FPE you want the gun to produce.... It's not a hard and fast rule, and you can get away with half that volume, but you will pay a price by having to increase the setpoint of the regulator to get back to the same power level.... This is why Motorhead said that regulators are best in the smaller calibers and for lower power, because you don't have to lose as much of the reservoir to the pleunum (volume downstream of the regulator, often provided by a "valve standoff", ie spacer between the regulator and valve).... I have several high powered, regulated, PCPs, but they have separate tanks and very large plenums.... Once so equipped, they are fabulous guns, but to do that you have to do things like reverse the tank, placing it below the original reservoir like this....



The upper rifle is a 2260 HPA, shooting 18 gr. JSBs at 960 fps (37 FPE), and gets over 40 shots from 13 CI of air regulated to 1600 psi.... The lower one is a 2560 HPA, shooting 25 gr. JSBs at 960 fpe (52 FPE), and gets over 32 shots from 17 CI of air regulated to 1800 psi.... Both rifles have the entire 2260 tube (65 cc) as the plenum.... They both have Lothar Walther barrels, custom repeater breeches, and Hawke 3-12 x 44 SF Scopes, and are set up for identical trajectories....

Bob