Anyone use a Drum spring?
I just installed my drum string and was wondering if anyone else uses one? I am trying to get a rough Idea of the PW settings in relation to the stock spring. I had the PW @11 w/stock spring and was wondering where to start with the drum spring. I would be testing myself ,but have been getting a lot of Chrony errors and a lot of pumping to get nowhere. Does a chrony light almost guarantee no more errors?
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If you aren’t getting the FPS you want with the stock hammer spring and the drum spring is supposed to help, I suggest fiddling with a lower TH setting. If you don’t want to change the TH valve settings you have, you can get another set, Hi-Flo Valve Pin, TH, and 2 new Grub screws from AF. Then, set up the new Valve Pin for the drum spring and save the other for when you want to switch back. I have 2 sets for .22 cal, one set at TH = 0.084″ and the other set at about 0.068″ for now. I can change the valve stem in the field for heavier or lighter pellets without having to screw with deforming the thin valve pin. All that is needed is either a screw driver or as I prefer, a plastic pry bar to remove the newer Hi-Flo Valve stem and maybe the tank safety cap or fill adapter to assist pressing the replacement valve stem in. I think Edward makes the change with the tank on the rifle. But I’m not certain of that. Then dry fire a few times to get the valve reseated. Caution, I was told that the older valves have a setscrew holding the valve pin in. You could ask AF if it will work with your tank when you order the replacement part.
Did you try it with PW set to ZERO?
Like the beginning of a good bath tub curve the first few shots have too much air pressure and blows around the pellet slowing it down. With a stronger spring I’d think you’d have to turn down the PW to get the same FPS.
That new spring may have allowed you to use less PW and if still over powered, a TH adjustment may have helped.
I had tried a few shots at zero and there was no rise in speed.
Does it snug over the PW same as the stock one?
I’m just thinking maybe its getting over compressed and isn’t releasing all its energy..?
It has an adapter that fits the PW and than the spring to the adapter. It probably adds a 1/4 inch in length.
Did you try it with PW set to ZERO?
Like the beginning of a good bath tub curve the first few shots have too much air pressure and blows around the pellet slowing it down. With a stronger spring I’d think you’d have to turn down the PW to get the same FPS.
That new spring may have allowed you to use less PW and if still over powered, a TH adjustment may have helped.
Does it snug over the PW same as the stock one?
I’m just thinking maybe its getting over compressed and isn’t releasing all its energy..?
I’m not sure now. The drum Spring is 4″ , the factory one is back in the gun now. I thought they were about the same.
Is the spring alot longer than the stock one?
Yeah, that is sorta weird on the spring thing…What brand chrony do you have?? I assume you are using it out doors? Lemme know..I had a LOT of trouble with mine, ended up being MY FAULT, not the chrony!!! Tll me all the particulars with the chrony, maybe I can help ya get it figured out 😀 😀
Got some shade now so Chrony seems to be working. I put the Stock spring in and back to usual PW setting, and i got that 30+ fps back. I just don’t get why the stronger spring would make it shoot slower.
Should be stronger, the gun is harder to cock on PW4 than it was with the stock spring on 13.
My guess is that it’s a weaker spring than the stock spring.
What do I win? 😆
Yeah I have pretty much gone through all the PW settings and found less is better with this spring. I got my best results at about 4-5, but still less than the stock spring. Was wondering if I should play with the TH at all or put old spring in and quit waisting my time?
Now I cant get any readings with my Chrony, so kinda fucked for now. Its sunny so I put the diffusers on and nothing, take them off and nothing. It will read my hand at 29 fps, but not any of the slugs I shot over it.
My biggest problem is not having a fill tank, sucks pumping every ten shots when trying to get numbers and make changes.
Good day to bitch and whine.
Try and up the pw?
Dave
With this new spring I am seeing an average of about 35fps less than with the stock one. Does anyone know why that might be? Trying to figure out if I should keep playing with it or go back to the factory spring?
Any help appreciated,
Thanks
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[quote=”packrat”]Yeah, that is sorta weird on the spring thing…What brand chrony do you have?? I assume you are using it out doors? Lemme know..I had a LOT of trouble with mine, ended up being MY FAULT, not the chrony!!! Tll me all the particulars with the chrony, maybe I can help ya get it figured out 😀 :D[/quote
thanks, but I think I got it figured out. I think the sunlight directly hitting the windows or lenses was the problem. As soon as it went behind the house the chrony worked again. I guess I’ll know for sure next time I try it. I did notice a wire got pinched when it got folded, but if that was the problem I figured it should never work.