Nice work on the 880 William. That new style GEO ldc looks good! I,m going to have to get one for my other 880.
Thanks, Bryan.Wll - I'm not sure what size the washer is. I think it's a 1/4" washer. If you look closely at the picture I posted, it is slightly thinner and a smaller O.D. than the black Daisy washers that hold the rubber bumper.
Hi Wil, it looks like you're making that 880 into a nice shooter. I shot one about 40 years ago and was impressed with how easy it was to pump.Maybe I'll get one...Don't know much about the piston or the gun, but I've had some experience with piston shimming.... and foil tape has never worked for me. I think that the combination of piston lube and condensed moisture releases the adhesive.. under high the pressure.. don't really know but it hasn't worked for me. I've have had good luck with JB Weld as follows:Texture the face with 220 grit so the epoxy has a better surface to grip:Thin the epoxy with acetone or lacquer thinner so it can be poured (it won't affect the strength):Face the shim to the desired thickness (this one is .010") and "paint" with cyanoacrylate to seal the surface:I've done a P17, HW75, and (2) Fas 6004 this way and haven't had a problem with any of them (knock on wood) That's a nice looking shooter you have... I'm starting to think that I "need" one Wyo
I assume you have no problem with the oil dissolving the JB weld ?
I replaced the rubber bumper with a solid stack of washers in my big bore 880 project. I found out that the rest of the parts can't take the stress and wear quickly. This increased headspace and power went down. Given that, I'm a fan of the rubber bumper as a means to keep from over-stressing the system and wearing out parts prematurely. But maybe you can find the stack to give you the perfect balance between power and longevity. It's fun to try. You really need to port the valve, drill the transfer port, make an extended slim probe, increase hammer travel, and install a stiffer hammer spring. And sand the piston head flat. I did one mod at a time and measured the improvement. Some were only single digit improvements, but they all add up.
Good point about the number of pumps. I was going for max power and used 20+ pumps. I think you should try it and see how it works in your case. I don't remember how much the hammer spring helped. Without it I would sometimes get valve lock.
I'm going to try to use the washers in place of the elastic spring .. and if I don't like that I will use Belleville washers, so I have a little give but not much ;- )wll
Well I took this baby apart ... it is never as easy as watching the video of the guys that have done this 100's of times ;- ) Well my 880 frame is not cut out like all the others I have seen ... a bummer for putting in the sear shim as I had to take the trigger out .. but I did it and it is a little better, but I needed more shim ... but I can live with what I did as it is about 15% better ;- )I also took out the pump and put JB Weld in the piston head .... that will dry for about 20 hrs ---- Also added the 901 Barrel sleeve ;- )I then attached GEO's LDC ...... Looks great ... you do nice work Geo ;- )Frame Pic Below:Geo's LDC Below:And now for the bad news .... Yes the safety spring and ball went flying to China ... man alive was I &^#%&* OFF !!! This means I will be calling Daisy Monday and ordering some springs and detents ... but I will order some more stuff too so I wont need anything else for many years if I live that long ; - ).wll
I just looked at the barrel shroud and found no markings other than the Daisy Powerline name, caliber and made in China markings ;- (I purchased this gun maybe 3ish weeks ago at Walmart.wll
Quote from: wll2506 on December 07, 2018, 11:39:52 PMI just looked at the barrel shroud and found no markings other than the Daisy Powerline name, caliber and made in China markings ;- (I purchased this gun maybe 3ish weeks ago at Walmart.wllThat's very odd- I've never seen or heard of an unmarked 880 before. Usually on the newer guns there'll be a number more to the underside of the barrel shroud than on the side like in the photo.But thanks for trying!Mark
Hope this helps.wll