by B.B. Pelletier We received this question last week. Because it goes to the heart of airgun operation, I wanted to address it today. i wonder is there a way to pep up the 1077 by changing valves. there is a company out there, which offers to upgrade co2 guns to higher velocity. i forgot the name of it. if you use your airsource canister only 200 times instead of close to 400 shots and double your velocity to close to 1000 fps instead, what a nice squirrel hunter you would end up with. i wonder why nobody ever asked this question. i read somewhere, this company does this conversion all the time or sells the conversion kits. btw canadian tire sells now the 1077 as crossman airsource 1077 and comes with the airsource can nicely snuggled underneath the belly. no fumbling around necessary any more. looking forward to your reply. cheers faustus
The age-old question! First, it’s a .177. Even if you get it up to 900 f.p.s., it’s still not ideal for hunting. Anything much faster becomes inaccurate. Second, the 1077 is mostly plastic. While the gun is accurate at the power level it comes with, increasing the power will put too much strain on parts not designed for that. It’s like the tires on your car. They are probably rated for 90 m.p.h. You can run them at that speed for a long time, though the manufacturer doesn’t expect you to. But try to run those same tires at 110 m.p.h. for a half hour and they may very well fail catastrophically – as in blow out! The third reason for not suping up a 1077 is that the sighting system isn’t made for it. If you have a gun with 900 f.p.s. velocity, you’re going to want to shoot it at long range. The dovetail on a 1077 is plastic, so it’s not able to give the precision required for high-power operations. It’s fine for shooting out to 30 yards; but at 60 to 75 yards, you will be at a disadvantage. Twice the gas doesn’t mean twice the speed! An analogy Airgunners see features they like in one gun, and they transfer them to a different gun or mentally apply modifications that aren’t really feasible. HOWEVER – and this is today’s lesson – there ARE certain airguns that respond well to “tweaking,” because they have much more potential than they currently deliver. The No. 1 airgun hotrod champion! The Steroid Streak Crosman 160/TF 78 Spring guns So, Faustus, I hope that addresses your questions. Anyone else who wonders what can be done with airguns, I hope this points you in the right direction. notec wrote: daxinfx wrote: Hmm, maybe the Drozd bulkfill CO2 adapter could fit... Go here for pictures: goolytf wrote: I recently bought a Beretta PX4 Storm Recon and I am wondering if there is some way I can mod it to increase the fps. I have no problem buying a new one if this messes up. So is there any suggestions of what I can do? That wont do anything for the FPS........CO2 no matter the quanitity stays a constant pressureI'd have to disagree with you Notec. Stop reading so many internet articles You can increase velocity by adding a larger resevoir (bulk bottle) even if the co2 is at the same temperature/pressure. This happens with hot mod'd valves..For example a bulked QB with extensive valve mods and porting will use alot of co2, the amount that's stored in the bulk tube isn't enough to keep up with what it needs for maximum power output. THink of the bulk tube as a capacitor. Now, charge the bulk tube up and take a shot through the chrono and write down the number.. Then take another shot and you'll already see noticeable drop.. If the tube was enough of a reservoir the second shot wouldn't have dropped but it did telling you that the first shot didn't have enough to begin with.. So by adding a large reservoir you provide more than enough gas for that valve to run at optimum power output.. If it wasn't so late i'd get into more detail but it's time to crash.. Page 2notec wrote: Quote: Sigh......your putting more into my post than was there. Maybe so..notec wrote: Quote: Or you just dont understand. Definitely not the case I was just responding to a comment you made about co2 that sounded vague and incorrect, you sounded like you were talking about CO2 in general, you didn't say CO2 in your Beretta PX4.. anyways.. i'm finished with this.. Page 3Little more info relating to CO2 pressure. Quote: What's the pressure in a CO2 tank? As long as there is liquid in the tank, the pressure in a CO2 tank is determined ONLY by the temperature. At room temperature (70 degrees F) its about 853 psi. (You can check this and the pressure for other temperatures in the little table at the top left of the CO2 diagram.) The pressure in a CO2 cartridge, as long as there's any liquid in it, can be calculated roughly from: p = p0 * exp(T/T0) where p is pressure in psi, T is temperature (Fahrenheit), and p0 = 314.04 psi T0 = 69.64 F This works pretty well between 0 and 80 degrees F as long as your bottle is filled to 100% or less of its rated fill. To get a more accurate estimate, use the CO2 diagram. Once all the liquid is used up, there's only gas in the bottle, and then pressure drops pretty quickly. 88 degrees F is the critical point for CO2, where all the liquid sort of evaporates no matter what (kind of complicated). Any way, above 88 degrees, the pressure depends on bottle volume again, but this is not too important since bottles should never get this warm. http://www.warpig.com/paintball/technic ... cs.shtml#2 Here is the source..............lots of good info here. _________________Jonathan Moderator Page 4
|