No need to bore out the grub screw threads to enlarge the port. Reach past the threads with a rotary tool using a carbide burr to enlarge the port by hand.
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Tuning FX Impact M3 35 cal power destiny
- Thread starter 7Green
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Alright- Here' a few pictures of what i'm considering using as an external plenum. Note: this will all require at minimum, some kind of adapter to bolt on the bottom of the powerblock. Or, potentially make a new valve block to incorporate it into a single unit. I dont feel safe at all just trying to have these big monsters hanging off the bottom of the valve block. In all honesty it may just be easier to make a new valve block since it's really nothing complicated. I already have a chunk of 7075 aluminum I could use.
The smaller bottle is a 9ci (147cc) tipmann 3kpsi tank- So i at least know its not going to blow up in my face. Working pressure on it is 207bar, test is 310 bar. The bigger tank is a 200cc chinese special off ebay that just feels a ton heavier and is way more cumbersome. I got that before i found the Tipmann tank. Here are some pictures. I'll definitely be going wtih the tipman tank for this simply due to the weight, size, and known manufacturer of it.
And some other possible configurations i was thinking of since a straight-stickout would be below the butt-pad and has greater potential to get knocked around unless i build a bag rider to protect it (Which is what im thinking would be easiest)
Off to the side wouldn't actually be bad placement- but then your face is resting on it. That's going to be a no. Too close for comfort
Just to see the width difference between the power plenum (37mm) and the tipman tank (50mm)
Just thought I'd post some pictures / "thinking out loud". Yes, for you people reading this who want to comment "you don't need a plenum that big!" Too big doesn't hurt a thing, and the effects of additional plenum volume on the Impacts have been shown to be benficial. From the days of the ole' yellow forum, 1cc per FPE of plenum was a good target to aim for. If we're trying to push 200 FPE with the .357 M3, having a total of around 220cc (72cc PP + 147cc tank+ volume inside valve and block itself), is close to being "ideal".
The smaller bottle is a 9ci (147cc) tipmann 3kpsi tank- So i at least know its not going to blow up in my face. Working pressure on it is 207bar, test is 310 bar. The bigger tank is a 200cc chinese special off ebay that just feels a ton heavier and is way more cumbersome. I got that before i found the Tipmann tank. Here are some pictures. I'll definitely be going wtih the tipman tank for this simply due to the weight, size, and known manufacturer of it.
And some other possible configurations i was thinking of since a straight-stickout would be below the butt-pad and has greater potential to get knocked around unless i build a bag rider to protect it (Which is what im thinking would be easiest)
Off to the side wouldn't actually be bad placement- but then your face is resting on it. That's going to be a no. Too close for comfort
Just to see the width difference between the power plenum (37mm) and the tipman tank (50mm)
Just thought I'd post some pictures / "thinking out loud". Yes, for you people reading this who want to comment "you don't need a plenum that big!" Too big doesn't hurt a thing, and the effects of additional plenum volume on the Impacts have been shown to be benficial. From the days of the ole' yellow forum, 1cc per FPE of plenum was a good target to aim for. If we're trying to push 200 FPE with the .357 M3, having a total of around 220cc (72cc PP + 147cc tank+ volume inside valve and block itself), is close to being "ideal".
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You should reach 200fpe easily with that. I think I can get there now with out an added plenum. I hit 193fpe at 180 bar and still could have adjusted my huma reg another 10 to 20 bar (200 bar rated) I elected not to because the first reg is poinless then. K&L makes a first reg delete kit that I have considered. I really dislike the 1st reg. It isn't all that accurate and is just more parts to go bad.
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Oops- brain fart. 1/2-20 wont work for .357. It's way too small. Next SAE size that would work is 5/8-24. Technically .578"×28 would work also, but thats fairly uncommon.
Here's a quick & dirty drawing of what i was thinking of. 27mm OD to fit on a 30mm OD x 1.5mm thick wall "shroud" with 5/8-24 thread on it, but that can be changed to whatever. The vent holes wouldn't actually be there, since they would be blocked by anything bolted on. That's mainly for another idea i have rolling in my head that negates the threaded part all together and uses the shroud itself as a moderator. You simply add more length to the shroud to go beyond the muzzle (another idea stolen from my other PCPs)
Here's that piece on the marauder which is closer to what i was thinking of
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I like it. Sounds like I am going to have to explain the need for a lathe to my wife some day haha
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I did this to my mk2 I've got to test it yet to make sure accuracy is still there and I saved 4 inches on length
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I just remove the butt stock to get it to fit in original case I have to test it for accuracy yet then I'll paint it
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I have just 2 air strippers fitted inside floating on 2 springs so they can move back and forth about a 1/2 inch and vented it to the rear with felt around the barrel it about 1 db louder than the other set up I had which was kind of the same felt around the barrel and large holes for air to go back plus a koi on the end which made it fairly long
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I used a high grade M14x1.25 bolt to connect to my first external plenum. Cut the head off and bored it to 9mm.
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