TargetTalk

pilkguns wrote: CA is depressurizing the entire length of the barrel while CO2 under some atmospheric conditions is building pressure as it exits the barrel, thus causing turbulence. Or so the physicists tell me.

Your idea may be correct if liquid CO2 iss released behind the pellet at discharge, and pressure increase due to evaporation of CO2 in the barrel behind teh pellet is overtaking the pressure reduction due to volum increase. I am willing to strongly believe both assumtions are wrong. Zorry about that. No bad feelings.

The old FWB CO2-2, with horizontal cylinder and no secondary chamber, cylinder well filled, may have come close, but...

Some stupid guest wrote:[I am willing to strongly believe both assumtions are wrong. Zorry about that. No bad feelings.

The old FWB CO2-2, with horizontal cylinder and no secondary chamber, cylinder well filled, may have come close, but...

in my limited understanding I absolutely agree with you. I have had the same questions/theory years ago, and have had it explained in great detail why I was wrong. I have learned its best not argue with expersts in their fields. The factories did the testing and determined that CO2 turbulence was causing incaccuracies that the previous gen guns (Model 65/80/90 basically) did not share and thus the compensators, or more correctly described, strippers. A compensator as understood in the firearms sense is not necessary for an airpistol.

With very limiting experience of vise-testing my LP10 without its shroud and compensator it is as accurate as with them on (one pellet hole size). I believe the crowning of the barrel has much more to do than the compensator in accuracy. Also the introduction of ported barrels allow much of the air to escape before the pellet exits thus reducing the air following the pellet.

pilkguns wrote:compensators in CA pistols are a leftover from CO2 pistols where they were a necessity due to liquid to gas transformation and the speed of the gas as it left the barrel. Today it is a matter that shooters expect to have them on their gun.

CA pistols accuracy are not effected in any way with them on or off the pistol.

sorry - but männel - a steyr tuner told me, the compensator was not necessary by CO2 but for CA.
The reason is the pressure profile of CA.
Remember the Steyr LP Match - the Walther CP1 - 3 - they are all without compensators.
excuse my bad english.

Sigma_30

Very interesting discussion. I´m just considering whether to buy a comp for my LP10 or not. I´ve also talked to Männel triggering the question and got the same answer as sigma_30.
Hope to find out more here in this forum.
Best regards

Max

Sigma_30 wrote: Sorry - but Männel - a Steyr tuner told me, the compensator was not necessary by CO2 but for CA. The reason is the pressure profile of CA.

I may be wrong, but it seems to me that CO2 gives an 'impulsive' expansion of gas through the barrel, while with CA we have a 'prolonged' expansion, that is to say a smoother but longer acceleration of the gas, through the barrel. I've read something like that, long time ago, on the 'Cahiers du Pistolier et du Carabinier' (French, good magazine). Now it is perhaps possible that with such a longer acceleration of the CA a compensator gives some help. But, as I've said, I may be wrong.

I don't which which Männel you are referring to ,but Gerd Carlo Männel, formerly president of Steyr-Sportwaffen, a good friend of mine as well, is one of the sources, I have also heard the same from Walther and FWB. Perhaps you got mixed up what was said?

Would that be the same Gerd-Carlo Maennel, whose "tuned" Steyr produced worse groups in its VISIER-review than the original LP10, and was more ammo sensitive?

Yes, I think they´re talking about the same Männel in Kronstorf/Austria near Linz. I have the VISIER-story (Visier is a German gun-magazine) just in front of me and one of the key issues is that a comp on air pistols in connection with CA is worth the money.
Max

pilkguns wrote:I don't which which Männel you are referring to ,but Gerd Carlo Männel, formerly president of Steyr-Sportwaffen, a good friend of mine as well, is one of the sources, I have also heard the same from Walther and FWB. Perhaps you got mixed up what was said?

Well - it seems - we have a little problem.
The fact is - your friend männel is talking bullshit !
Either to you - or to me.
But you can be assured - the problem will be cleared next year during the german Championship.
There i will meet your friend and confront him with his statements.

Best regards
Sigma_30

The influence of compensator on the more shot accurasy is growing with the more muzzle presure and outgoing gas mass. It is approved reality many a time. Air or CO2 is not important for this once.

Regards Petr

wrote:The influence of compensator on the more shot accurasy is growing with the more muzzle presure and outgoing gas mass. It is approved reality many a time. Air or CO2 is not important for this once.

In more detail: it is the velocity of the gas (a function of pressure and temperature, among other things) as it passes through the compensator that matters. Along with the density of the gass, and the total mass of gas. As you may just have guessed, it is a matter og momentum, the integral of mass times velocity of the gas.

CO2 is considerably heavier than air. Is the muzzle pressure of CO2 guns lower than that of PCP guns? Frankly, I do not know, but I think it is. The CO2 gas is denser, and each molecule is much hevier than an "average air molecule". But the pellet "does not now" which gas is propelling it...
I'll try to find and bring references to this interesting topic.

Forgot that, the turbulence. I'll return to this important topic in a future post.
The gas velocity and mass may be determining the compensators recoild reduction. But in this thread we may need to take a closer look at turbulence in, and in front of the compensator.

I'm not sure the main effect of a modern air gun compensator is its impact on recoil. I always thought a big part of the idea was to strip off the rapidly expanding gas in a safe direction to that the turbulence didn't affect the flight of the pellet. In reality, they presumably do both. The first compensator I ever saw was the aftermarket Turbo-Comp from Nygord, and I think it was sold with both effects in mind.

I think the problem is the term "compensator", which folks immediately equate with compensators for firearms, where recoil reduction is the goal.

Gwhite wrote: I always thought a big part of the idea was to strip off the rapidly expanding gas in a safe direction to that the turbulence didn't affect the flight of the pellet. In reality, they presumably do both.

You are right. In the airrifle community the comp is nowadays called an "air stripper".

I found som links to rocket engine excaust venturies, but no links to turbulence control yet.

i don't have plan to use new kompensator. Why ? korean shooter can break world record with old kompensator. So would i break world reccord if install new one ? i don't think so. Maybe i will purchase new grip.