Airforce Sweet Spot 101 by Mac1 Airguns

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Air Force Sweet Spot 101

January 1 2009 at 12:29 PM mac1airgun@gmail.com”>Tim McMurray Tim McMurray (Login Mac-1)
YFOT
Before I deliver AF guns I always set them up for relatively low charge pressure (Max 2400-2600 PSI) and maximum shot count so you can get maximum number of shots before you need to refill your tank.
I turn the owners manual over and list on the back; Max Charge Pressure, Velocity range, Pellet weight, Energy, shot count & gun setting.
The Talon SS 12″ barrel .22 gun should be set-up with no more than 20 ft. lbs. of energy if you want 40+ shots per charge. 10% more power will cost you about 20% in shot count.
The Talon 18″ barrel .22 gun should be set-up with no more than 25 ft. lbs. of energy if you want 40+ shots per charge. It can be pushed to 28 fpe to get about 30 shots per charge.
The Talon SS w/24″ barrel .22 or the Condor 24″ .22 with standard talon tank and no hammer weight should be set-up with no more than 30 ft. lbs. of energy if you want 40+ shots per charge. At 35 fpe the shot count goes down to 30.
I shoot for a 30-40 fps spread from high to low shot when calculating shot count that will stay in a reasonable size group at long distance. Most of these guns when turned up will shoot harder with high pressure but at lower pressures they will simply make more noise and waste air.
The performance level that seems to give the best accuracy and shot effieciency is a setting on the gun from 0-4 on the wheel and a .100″ gap between valve top hat and the valve face.
The guns power adjustment simply changes the preload on the hammer spring and when you make a change of that nature there will also be a change in the optimal minimum and maximum charge pressure.
The ideal gun will drop about 40 fps from max speed when charged beyond 2500. It may give 760 fps at first and then climb up to 800fps as the air charge drops during the first 15-20 shots. For the next 15-20 shots the velocity will fall back to 760. That is the best way to get the max number of useful shots per charge. It is called using both sides of the bell curve. If you plot charge pressure on the horizontal axis and velocity on the verticle axis a properly set up gun will display a bell shaped curve when graphed.
If you stand on it the velocity will only drop every shot so you can’t get as many shots within a useful range.
Once you have the gun’s wheel setting giving this situation you can use the valve head adjustment to adjust the power up and down for various pellets and usage. The top hat adjustment is similar to the power adjustments on the Korean PCP’s where you are adjusting the amount of valve lift which won’t change the optimal min and max charge pressure.
The more power you want to make the heavier the ammo you want to use to keep the accuracy good. I wouldn’t use ammo that weighed less than 15 grains but you can go up to whatever you can find weight wise and it will just make more power the more pellet weight you fire.
Efficient guns tend to be more accurate and get far more shots per charge.
Consequently the heavier pellets will not only shoot with less report but they will also get you more shots per charge given the same power setting. Your either making power or your making noise with the air. Your choice. The more you crank it up the more noise it will make. Unless you also feed it heavy ammo your accuracy will suffer.
After spending some very frustrating times with customers lately trying to get them familiarized with their Condors it is obvious to me that some need a bit of schooling in the art of the consistency most of these guns are capable of.
In stock form with high flow tanks and hammer weights if the top hat to valve face adjustment isn’t narrowed a bit the Condors will be unable to shoot below 1050 fps with 21.2 grain Kodiaks when shot from 2200-2500 psi.
Straight from the Box all AG’s vary but the Air Force guns seem to have taken this a bit further with no two actions or tanks the same. Makes for an interesting assortment of what works on different rifles. A lot of folks want to have two tanks that perform similarly and this can be exasperating as any time spent trying to accomplish this will reveal.
Best is to teach folks to fish rather than do all their fishin for them.
You can’t just slam 200 Bar(3000 psi) in these things and expect them to do one holers for 50 rounds.
Nearly every gun I see has the power adjustment turned to the absolute max and the guns will simply string verticly because there is no bell curve. Every shot is less velocity than the previous one.
Shooting for the moon performance isn’t going to give you the accuracy we have come to expect from well set-up long barrelled Talons. We built over 100 of these before the Condor and high flow tank were even available.
The factory is going for the mass market so the Condor power thing is a reasonable play from a marketing standpoint. Accuracy nuts should try the trick of taking the hammer weight out and fitting a standard Talon tank. You’ll find out what kind of accuracy these guns are capable of and stop pissing off your neighbors. No mods required.

“NO GUNS WOULD BE A RIOT”

Later

Tim

Mac1 Airgun