Pumps and FPS

[OPBN]

I was fiddling around with my pump mag today. Using 12grams and a devolumized/capped valve, and external reg. On max output on the reg, I am getting the first maybe two or three shots total over 300 fps. If I crank it down so that the first shots are under 290, I fairly quickly drop to the 260-270 range. While not horrible, seems a bit unfair that I would have to play most of my regular shots at less than the field limit. Anyone else run into this? How militant are fields on 12g pump FPS? I know with my other mags, if it sits for a little bit, the first shot is usually higher than the field limit, so I will usually fire off a few shots when I first step up to the chrono so that I don;t get dinged for high FPS.

Thoughts?

I have a couple of old threads regarding the build and I didnt want to necro post. Details on the marker can be found here: http://automags.org/forums/search.php?searchid=3839478

[hill160881]

Maybe liquid is getting through on the first few?

[OPBN]

Maybe liquid is getting through on the first few?

Through where? I am using a Micro CAII and Bob Long reg. The liquid would have to make ithrough both of those as well as the 8-10" of macroline.

I was pretty happy with the overall shots per cartridge. I got about 25-26 useable shots even with the FPS turned down enough for the first couple of shots to be under 290. Outside temp was cold, but I was standing in a back room of the house shooting out of the back door. I have a feeling, on a nice warm day that I could have probably gotten even better.

I guess I also wasnt really complaining about the high FPS on the first few shots as much as I was about what is the general policy on markers using 12g's? I would think some loss of FPS after the first shot or so would be normal for any marker running 12g's? Isnt it?

[shives007]

My hunch is that you have so much space to fill up, you are loosing all of your pressure in those first couple of shots. Even with the capped valve, you have a lot of space to fill.

I have played some fields/events where you need to put in a fresh 12ie in front of the chrono ref. Your first couple of shots need to be under. However, some don't care much.

Shives

[shives007]

My hunch is that you have so much space to fill up, you are loosing all of your pressure in those first couple of shots. Even with the capped valve, you have a lot of space to fill.

I have played some fields/events where you need to put in a fresh 12ie in front of the chrono ref. Your first couple of shots need to be under. However, some don't care much.

Shives

[skyless]

Similar results here

I have experienced the same thing. First few shots seem high then it levels off. I also run a micro ca II. I really want to try using a female stabilizer directly to the micro ca and see if it evens things out. I think double reg 12grams may help with consistency. Hope through AO collaboration we can get some solid 12gram setups. I'm also breaking 25 shots per 12gram. Devolumizing the valve made the most difference. Putting 12grams direct to the valve was very inconsistent and inefficient. The micro ca II under grip iis the best option IMO.