Right, im thinking a short blast of 2000 psi would definitely scoot the pellet along faster than rhe same volume at 1500.
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Paintball regulator and plenum sizing
- Thread starter Dr. Kralenstein
- Start date
Well, it looks like if you added some AIR, then you could see where it's at velocity wise? hint, hint?
I'm willing to bet a 18" barrel makes more of a difference than more reg pressure, but then it wouldn't be as short. The shorty bottle build in my pic actually shoots below 12 fpe with a 1800 psi output reg and everything else the same. Diminished return due to not enough barrel, or possibly hammer spring, but I didn't want to fight a heavy spring and the wear and tear on the cocking pin, so I'm fine with 17 fpe lol!
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Still waiting on the regulator to show up then it's just test/tune til get where I want. Making the stock will take the longest time.Well, it looks like if you added some AIR, then you could see where it's at velocity wise? hint, hint?
I'm willing to bet a 18" barrel makes more of a difference than more reg pressure, but then it wouldn't be as short. The shorty bottle build in my pic actually shoots below 12 fpe with a 1800 psi output reg and everything else the same. Diminished return due to not enough barrel, or possibly hammer spring, but I didn't want to fight a heavy spring and the wear and tear on the cocking pin, so I'm fine with 17 fpe lol!
I'm used to building these unregulated just using a filled tube with 3000+ psi. If I can get a mouse farther quiet 10 fpe 22 I guess I'll be happy.
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I've got a 15 ci carbon fiber bottle on order for my Prod. I'm going to plumb it in to the gauge port and use the tube for a plenum.
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Well I ordered a drop block power adjuster heavier spring and butt stock for my prod 22 I have a few bottles and regs all ready plus a 22 mrod barrel for the project I may just gut the reg bonnet and go unregulated bell curve for it the drop block I got screws into the end of prod tube to so I can use the whole tube for a plenum to
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That's my plan if the regulated 1500 psi doesn't get me in the ballpark of where I want. It's such a small amount of plenum, im guessing less than 10cc.
Haven't measured it yet, might get out a syringe tomorrow and see how much it holds. I hope it works since the bottle I have coming is 4500 psi, should give me a ton of shots even with the 250cc size.
Otherwise, I'd be limited to about 3500 psi with the amount of hammer spring you can really put on a stock 2240 striker without mods. 250cc of 3500 psi would still give me a bunch of shots with ALOT more power and noise. Would make a pretty mean slug gun if I find one it likes.
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I'm glad this inspired you to build your Prod. I wish I could find a multi shot breech for the 22xx, seems the one maker in Thailand is MIA currently. That and it would make the barrel and shroud sit up so high above the bottle I wouldn't want to look at it lol.
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You sound like me. Have multiple builds going at the same time. I'm constantly changing my gun parts around making different setups. 22xx platform guns are legos, so are Krals I have found out.
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To be honest, I'm not usually like this. I just happened to have a few things fall into my lap at the same time.
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I had a couple different brands of the repeater breeches and all had issues with accuracy. I think it was do to the fact they all used a little bushing for the leade/transfer port and this bushing sat in front of the stock barrel leade. It made the pellets tilt or jam up sometimes. I had one even get locked up and had to cut the bolt out to get it all apart.
The sidelever kit from the Russian guy I have heard are very good units, but I'm not about to spend close to 300 bucks for this project gun.
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can't you just bore out the "plenum" on that drop block?
you mean the "plenum" is threaded inside right
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The way its designed you can't really bore it much past 5/16". The transfer tube that goes from block to valve has a drop section on it. It's there to give you space to mount the front trigger frame screw. Otherwise the tube would be right on the other side of the threaded hole and it'll strip the threads trying to tighten the trigger down. His older design was like that, but could be ported more.
So that tube between the block and valve is your plenum on this. It's threaded and o-ringed on both ends, one on block side, one on valve side.
I did have the maker chop my plenum tube down 3" so I could shorten my 2240 gas tube down to just past the front trigger screw. Wanted short as possible, didn't think about plenum size at the time.
In its stock form, I would think his design would still get you into the 15-20 fpe range. I don't think plenum volume on a 177 or 22 is as much of an issue as it is on larger calibers.
Ever seen the "plenum" on a benjamin fortitude? It's TINY and they still get into the 15 fpe range on the 22 model. The plenum is basically a small dished section on the back of the tiny regulator and it meets up directly to the gauge block with another small dish. I wanna say it's something like 6cc worth of plenum.
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A comment about the Fortitude. I haven't been into one but supposedly it has a large orifice that allows the reservoir to augment the plenum during the shot cycle. Something like that is a compromise against the device's input regulation characteristics.
At the same time, a 6cc plenum isn't too wildly undersized for a 15fpe power level. For in-tube regulators, sizing the plenum to something closer to 0.5fpe/cc will yield the best balance of power and shot count because allocating a large plenum (e.g. the 1fpe/cc guideline) simply steals precious volume from the reservoir.
At the same time, a 6cc plenum isn't too wildly undersized for a 15fpe power level. For in-tube regulators, sizing the plenum to something closer to 0.5fpe/cc will yield the best balance of power and shot count because allocating a large plenum (e.g. the 1fpe/cc guideline) simply steals precious volume from the reservoir.
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I just know when I gutted my fort, it was the smallest regulator and plenum I've seen. The valve is also shorter and didn't seem to have much head space or whatever you'd call it between that gauge block and the valve face. The gauge block also had a small hole through it like the disco has.
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This is what I'm working with. 
Like i tell the ole lady, It's not much but it's what God gave me!
Like i tell the ole lady, It's not much but it's what God gave me!
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