FX Any plans for different sized DRS Plenums?

[Jlowe]

Good post! I just read your post. I had bought the same FX DRS Classic 22cal 600mm and bought the larger plenum. I had the same results you did. Mine came shooting the same exact power yoursdid. I just wanted more shots and that was the only reason for buying a bigger plenum. I'm going the route of the carbon fiber tube next week. I really like the concept of this airgun being lightweight and was just trying to maximize shot count. I thought the 600mm might be a little long, but now that I have it in hand I've changed my mind. I wouldn't mind having another one in 700mm in .25cal shooting light slugs. I think with the synthetic stock and carbon fiber airtime it would be really light weight.

 

[Normkel]

I just felt it was too much for the standard DRS. I'm hoping and holding out on someone to make a 20-30cc plenum that's the same size as the 12cc plenum. When I plugged it with the wooden dowels, it dropped the volume to about 30cc, which was plenty. To me it lost a lot of efficiency with that large plenum and I was refilling the air cylinder more frequently than I wanted to. Also, I was not a fan of that large block of aluminum hanging down below the stock, I think the standard plenum looks much better.

Could one put the blank plenum into the drill press and drill some holes to create the desired volume?

 

[Leatherman]

The blank sub 12 plentum is the same size as the standard. The standard is drilled out to the max of 12cc. or pretty much to the max as it is. No way to get up to 21 less 30cc . Tango Sierra posted here on Page 2 of this thread that he had figured out the size that would be needed to be able to core out 21cc but it had a recessed plentum gauge which took up room in the plentum. He then posted another version with an outside plentum gauge that had 30cc of volume. These two plentums still have to be lengthened about down to the level of the trigger guard. Here are his pictures showing the standard, SHP and his mid sized model In the middle. I have the SHP with wood dowel plugs which I feel gives a nice amount of volume to push heavy pellets or lighter slugs at around 30cc. I would rather see a mid sized plentum made that still has a volume of 30cc . That way one could just add a small plug to tune the gun for lighter pellets and maximum shot count. Although I’m not sure you could probably do the same with a 30cc and just lower the preasure. I myself am fine without a gauge on the plentum. It is very easy to just fill the gun to 20 bar over your desired plentum preasure and shoot a few rounds over a chronograph at a target. As soon as the impact changes nand the preasure per shot changes, check your preasure on the tank gauge and you have the plentum preasure. If you run a digital gauge, you can accurately determine how many bar is used per shot and then calculate how many shoots from 230 bar to the plentum preasure.

 

[Boss429]

I think everyone with a classic DRS is thinking about a mama bear sized plenum!
My thoughts are I'd want mine to have a 25mm digital gauge inset in the base and have about 20cc capacity. So...
Easy enough to throw one into Solidworks and print it for a trial fit (non-pressurized duh!).
Original plenum is 29.5mm tall and 11cc. The SHP is 100mm tall and 63cc. The TSP is 50mm tall and ~21cc.
Pics help show the idea and scale. Just wish I had a CNC mill next to the 3D printer.

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easy enough to make on the 5 axis