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What size bullets did you shoot? Thanks.
Well got my 308 to shoot 800fps with a 2800 fill and an .080 tophat gap power wheel on 5
Got it to fire filled to 2800 and boooom forgot. to top off when I left. But fired one more ran to my car drove to the closes crony witch was at mac1. Fired it again and oops forgot to tunn on the crony that was shot 3 shot 4 threw. It 741fps witch I feel is ok for the 4th shot pluses a few dry fires.
Got the 308 going but I keep getting valve lock I think going to drain down to 2800 then see if it open. And I ha. 12 lb spring might need to up it to14
308 is ready to fire just gotta want for the two trigger pieces. Its now a side cocker with a safety notch do wana crush my finger. But I just realized I for got to order rounds my badi guess I got cought up. As soon as I can send pics ill have some one start posting pictures ASAP.
That was not because of what it was made of it was how it was machined. My .308 valve is only .030″ thick and I’m hitting it with a 13 lb hammer spring with no problems. .25 is the same and has never failed either.
I didn’t want to use SS for the valve stem due to the issues that were had with sleph valves (stem breakage).. I did make a couple of seals out of delrin/ acetel and am hoping that it dosn’t try to push its way out the front, if it does then i will go with the stainless seal and lap it in to get a good seal.. The way i figure it it wouldn’t need much of a press fit to keep the seal on the end of the stem along with the valve spring pushing on it you have the tank pressure holding it there as well.. My stem OD is .312 and the seal is .375 in Dia wich is the same as the condor seal the big differance is that i went with .257 ID on the stem and 3 .150 dia ports on the end of the stem to let the air in… I will start a new thread tomorrow and post some pics….
Greg
Valve is done waiting on stupied AF to re ship the rest of my trigger. I uses 303 for my valves its easer to machine then 304 but just as strong. The 308 is close to fucking shit up down range. Just hoping I don’t suck this spring in the valve out. I also thought of using metal to seal it. Just not worth it so I did aceitel. Messing with tap and dies that small is not fun.
One thing that I think Blod and Baz has done, is have the seal in the end of the valve body, like a hollow cylinder of delrin and then that means that the end of the valve stem can be metal.
Food for thought….
This one is 303 stainless. I use 304 stainless. Might work but why not use acetal. For one you would now have to thread it and screw it on. Now you have to lock tight to make sure it doesn’t come undone and would be hard to take apart. How big are you making? Remember that the bigger it is the harder it is to open. On my .308 the stem is .375″ but where the seal is it is .312″. I’m running 13 lb spring to open valve. I made one .375″ and valve would not open all the way with 3000 psi fill and I wasn’t going any stiffer on the spring. I have no problems with acetal seals and it only take a few miniutes to make another one if changes are needed.
so what are you gonna use as a valve seat/seal?? I’ve started tinkering with some WAY over sized valve stems and am gonna try to use stainless as the valve seal and lap it to the valve guide so that they seal.. I’m thinking that with 3k psi it should seal up but who knows… also what did you make your valve stem out of?? I used 4140 and am hoping that it holds up….
Greg
Flaming hot Cheetos…I hope you have some asbestos toilet paper!!
Thanks again. Sorry for the crappy pics its my phone. When all complete. I see if I can brow a better camera
Here’s some pic’s
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Oh 118 my bad