*AIR TUBE/VALVE LOWER RECEIVER
Our air rifle project just received 2 daisy 599s. On initial inspection these rifles are built like a tank. Typical BSA quality with very stout receiver, barrel, action and air tube, and the bluing is very nice. The stock is of good quality with very good inletting-not a sliver or gouge to be found. The forearm is much more rounded than the Challenger, and the grip wrist area is smaller as well. All measurements are a little bit smaller (see list below) making this suitable for shooters who do not fit the Challenger. Gammo sights front and rear. Soft rubber butt plate-not plastic, metal inserts for the metal rods on cheekpiece and butt plate adjustments. All possible air leaks except the transfer port with its two associated O rings, and the barrel chamber O ring are contained within the removable cylander/valve in or on the exterior of it. The physical size of the brass transfer port itself is large with two substantial O rings that aligned well with the barrel/probe and is not pressed into the receiver. Within the very smooth interior of the action tube rides the hammer within a plastic (?) shuttle for essentially a friction free travel. There is no adjustment for travel length on the hammer, but there is a fine threaded adjustment for spring pressure for the hammer that can be reached and adjusted with an allen wrench from the back after taking the barreled action out of the stock and removing the plastic plug on the end of the action tube. When the hammer spring tension is backed completely off ie counter clockwise until it stops, you have 16 turns clockwise until that plug is flush on the spring side of the part it’s screwed into ie max travel. It will fall out if you keep going further. That piece needs to be lock tighted in with green penetrating thread lock from the back once you have the rifle tuned. This particular rifle came set maximum spring pressure, and if you leave it alone and don’t turn it any it will be fine, but if you turn it and break it loose it will not stay put without lock tighting it.
*BARREL/UPPER RECEIVER
As you can tell by these pics it is a very heavy duty barrel and receiver. The T handle bolt has a sleeve (some manmade material) over what appears to be a steel bolt. I didn’t take this part out because it was too locktighted up (no spare parts available yet!). There was a lot of grease up at the head of the bolt where it locks, so it was hard to see for sure, but it looks like it has one good sized spring loaded ballbearing in the head of the bolt that snaps into a detent for lock up. It is very secure. The charge air flows through the center of the probe, O ring is in the barrel.
*TRIGGER HOUSING
Typical style of BSA pcp trigger. I did some stoning work on the sear and where the trigger rides on the lever in particular. The sear wasn’t bad, but I just couldn’t leave it alone. There were some rough machining marks where the lever touches the trigger. To get the weight near legal I took one coil off the trigger spring, and one coil off of what they call the second stage spring adjustment, and adjusted that adjustment until I was near my weight. I would be very careful adjusting the sear engagement adjustment on these as it hooks directly to the hammer, which in turn rides in the receiver with some clearance. As this isn’t a true two stage trigger, the first stage you are pulling is thin air. I didn’t adjust the sear engagement from factory. I feel a very slight movement before it breaks on the second stage that’s fine. It passed every bump test I gave it. This safety blocks the trigger not the sear. 2009 safety blocks the sear.
PICTURES
Enclosed are side by side comparison photos of the 599 and a 2009 and an initial crony string of 164 shots from the factory setting with 3200 psi (that was all the pressure I had). You can see from the numbers that if I had 3365 psi the numbers would be smaller on the front end of the string producing larger extreme deviation.
We are just a small 4h air rifle project-we don’t have an air compressor, and it is hard to get a bottle filled around here above 4300 psi so I don’t plan on doing any more crony work in this area but for people who have scuba bottles and or a 4500 psi bottle I took the time to work up a 100 shot string, albeit much slower than the factory string, but plenty fast enough to cut clean holes in paper with a much smaller extreme deviation.
At this time I cannot see to accuracy test, but I have an eye exam scheduled in the near future. I have a stigmatism in my shooting eye and cannot focus on the front sight because it’s about 4 feet too close for my eye. If my daughter gets home before then I’ll have her accuracy test. I would expect these barrels to be very accurate due to their history.
COMPARISON MEASUREMENTS
599 2009
Overall weight approx. 3oz more
grip wrist circumference: 5” 5 1/2”
rear of receiver to muzzle 23” 29 1/4”
Back of wrist to face of trigger 3 1/4” 3 1/2”
rear of receiver to muzzle 23” 29 1/4”
from center of butt plate curve out
To the front of the grip 9 1/2” 10”
To the face of trigger 12 1/8” 12 1/4’
To the front of the probe
with action open 14 5/8” 15 1/2”
To the back edge of rail 17” 18”
Back of wrist to face of trigger 3 1/4” 3 1/2”
rear of receiver to muzzle 23” 29 1/4”