11 replies to this topic

[kickass jb]

I CPVC modded my SM1500 (plan to have 2 CPVC barrels and 2 PETG barrels in the future) and I range tested at different pumps and I found that after four pumps, the range actually decreased for every extra pump (up till 7, when I stopped) that I did. Just thought the added air pressure would make it go farther but guess I was wrong.

[Team Slaya]

Yeah, i noticed that as well, when i crayola/pvc modded my SM1500 ( it's temporary, i don't have any brass ). I pumped it up 14 times and it got better and better as i lessened pumps from 14 to 10 to 7, but i never assumed 4. I'm gunna go try that right now....

TS

Edited by Team_Slaya, 31 May 2005 - 03:16 PM.

[Uncle Hammer]

Hmm I cant see how thats so, your guns must be messed up. Because if you plugged that pump its not gonna release any air, it will keep building(unless you have a leak or something). So something is wrong with yolls guns., beacuse the theaory should be something like the more you pump, the higher the pressure, the farther your dart flies.

[NerfMonkey]

Could it be something wrong with the firing pin/trigger? I screwed up one of my AT2Ks doing the Bic pen mod, and now it has nothing on the pin in place of the spring, so when I pump it more, the pressure is indeed higher, but it makes it harder to pull the trigger, so it lets out the air rather slow instead of in a quick burst. Check your triggers and pins, see if they're normal.

[kickass jb]

Nerf monkey say you were right, then technically when I only used four pumps wouldn't I get even LESS range because its letting lower air pressure slower as well?

[cxwq]

It's probably that your dart/barrel arrangement is not well suited to the extra pressure. If your darts appear to 'wobble' in flight when you pump beyond 4 pumps, this is most likely the case. In general, for air guns, you want a relatively loose sliding fit between dart and barrel and you need a longer barrel and bigger weights to deal with increased pressure.

For a 4-barrel SM1500, your barrels shouldn't be under 6" and 7" is probably better provided they are a proper fit. Your darts should have 1/4" steel weights at a minimum, 3/0 is optimal. If your barrels are too tight or too short or if your darts are too light, it would easily explain your results.

Moved to mods...

[duce]

That exact same thing will happen with any pump gun and with some spring guns. Whats happening is that there is too much air being released for the dart wieght. The amount of air being released causes the dart to fly spin and flop around in the air thus reducing the ranges. This is why some people make loser darts. They add weight to their darts so when they use a more powerful gun, they can pump it more to get better ranges.

Cx beat me.

Edited by duce, 31 May 2005 - 04:18 PM.

[AirApache]

That's quite a few pumps you're doing there. Once you've plugged the overpressure release valve it is important not to do that unless you want plastic shards in your face.

[JSkater]

Wait, you pumped a release-valve plugged 1500 14 times!? Why, man? WHY!?

Edited by JSkater, 31 May 2005 - 07:41 PM.

[Team Slaya]

Wait, you pumped a release-valve plugged 1500 14 times!? Why, man? WHY!?

Well, i just go on the general rule of "If it gets damn hard to pump, don't pump anymore" with plugged pumps. 14 was the max that i could do until it was really hard.

[AirApache]

See now try that when you get some muscle and you'll have some minor surgeries to deal with.

[cxwq]

Well, i just go on the general rule of "If it gets damn hard to pump, don't pump anymore" with plugged pumps. 14 was the max that i could do until it was really hard.

There's something wrong with your pump if you can get past 8 or 9 pumps without blowing up your tank. Mine gets "damn hard to pump" at 5.