Anybody hear of these ? they use the same brass base and you screw in a larger valve body to allow it to meter more co2 ...word is it can make the
.22 cal QB shoot at 800fps !!
Magnumair gvasilovich@cogeco.ca
Report #1
Full mod HPA build on stock QB78 using MAGNUMAIR custom valve. These are simple observations on the valve itself as I’m awaiting the new QB78 from SNIPER (if he’ll ever get around to answering my PM) and a new chrony which will be what provides the raw data for comparisons on the results of the build. Note that I have two custom valves – one in brass... and one in aluminium. All comments below apply equally to both unless otherwise noted. The future build will use the brass valve (the other is for a separate project).
COST – You will be looking at $50ea plus shipping. Before anyone goes ‘aaarrgggghh’ please note that each of the pictured valve backs (you get the back only...and use your stock valve front and internals to put it back together) represents a ‘one off’ machining operation. Considering the number of machining steps evident on each valve I can say from experience that the actual time spent on each valve represents far more value than the amount charged for the valve. Also, be prepared for some ‘back and forth’ messaging as the valve will be constructed to your needs......ie: what do you want to do? Is it CO2? Is it HPA? Also included were some informative and friendly suggestions on what to do to optimize the valve.
FINISH – Excellent. Smooth with no machine marks of note. All sharp edges are broken and it is obvious on inspection that equal care was taken on machining the inside surfaces of the valve. The OD of my stock valve is .7440. The brass valve miked at .7441. Wow. (Yes, you read correctly – there’s a 1/10,000 difference). OK, lets be realistic.......the machine used was probably capable of cutting to 1 thou tolerance by taking EXTREME care. That’s not really needed for this application and I would of been quite pleased to see something within a couple thou. Nevertheless, considering that the parent stock round brass rod was probably .750 a couple of cuts were needed to get it down to dimension and the result is pretty impressive
FIT –. The internal threads were clean and crisp...and they threaded onto the front of the valve with minimal slop and no interference......also nicely done. Both ends were faced cleanly and all milled slots were crisp and on center. There were a couple of ‘off center/on axis’ holes drilled in one valve that take a bit of fooling around to do right. These were done right.
FUNCTION – we won’t know that until I actually get the gun built but I suspect that the concept is to provide a larger immediate reservoir (thus the longer valve back) as well as a few innovations that assist in the flow of pressurized air/C02 from the main tube. These innovations.... some I’ve seen (similiar - same concept) ...and some I haven’t. Therefore you’ve probably noted that there are no photo’s of the ends or interior of the valves. This is on purpose as I don’t feel that it’s my place to disclose someone else’s research/development. If they want to do that then great....otherwise I suspect that you’ll have to purchase one to find out what’s really going on.