MarauderAirRifle.com

Hope this help. I did this many many years ago. It is from my older Air Arms S310. The tube is carbine length so it is 210 cc.

Well, I just pre-viewed, and the graph looks too big for the display, and I only know how to re-size using HTML. So if you want to see the entire graph, More information can be found here
http://hamcontact.com/s310/

Hi Joe B. Glad to see you here. I have some of your stuff and it is top notch.

With my .25 I'm getting 24 shots from 2800 fill to 1900. So 900 psi for 24 shots. Average @ 800 fps.

Crusher

How do these look? The settings are at the bottom. Colums did not line up very good.

7.9 Crosman Priemier HP 7.9
Str 1 Str 2 Str 3 Str 4
Date 07/05/14 07/07/14 07/07/14 07/08/14
PSI 2700 2600 2600 2650
FPS 875.5 872.4 875.8 883.1
FPS 880.9 874.3 881.8 878.1
FPS 867.0 871.3 879.0 881.1
FPS 881.9 875.3 878.9 879.8
FPS 887.4 877.9 872.1 876.0
FPS 879.6 878.6 878.9 876.3
FPS 874.3 875.5 880.1 881.5
FPS 878.5 870.4 876.1 880.1
FPS 882.8 874.4 877.7 870.5
FPS 878.5 877.4 876.2 880.0
FPS 886.4 881.4 880.1 886.5
FPS 880.5 880.6 876.4 884.0
FPS 878.5 879.6 881.3 880.4
FPS 887.2 881.6 875.8 885.0
FPS 886.0 888.7 886.7 885.1
FPS 885.6 884.1 885.7 886.2
FPS 892.5 883.4 876.4 879.7
FPS 888.5 885.8 880.1 884.5
FPS 891.5 878.5 876.7 874.6
FPS 883.2 871.2 886.0 879.7
FPS 888.4 890.2 884.6 884.0
FPS 890.9 882.5 886.5 882.2
FPS 885.3 882.9 896.1 890.7
FPS 890.5 879.6 880.7 883.4
FPS 883.6 887.6 880.5 885.4
FPS 884.4 883.5 888.4 881.7
FPS 882.4 883.7 884.9 877.5
FPS 884.2 881.2 881.7 879.2
FPS 881.3 880.4 877.9 875.4
FPS 888.8 873.9 876.4 873.2
FPS 884.7 880.4 892.4 881.6
FPS 883.7 882.9 875.6 879.7
FPS 884.9 881.4 884.0 885.7
FPS 879.9 880.3 881.6 880.8
FPS 877.4 874.4 886.6 878.1
FPS 877.4 875.4 882.9 874.5
FPS 878.3 871.6 881.8 877.4
FPS 877.6 880.2 878.8 875.2
FPS 877.5 878.2 879.1 869.6
FPS 875.5 876.2 877.3 869.2
PSI 2150.0 2200.0 2200.0 2200.0
Total 40.0 40.0 40.0 40.0
Start psi 2700.0 2600.0 2600.0 2650.0
End psi 2150.0 2200.0 2200.0 2200.0
Dif 550.0 400.0 400.0 450.0
High 892.5 890.2 896.1 890.7
Low 867.0 870.4 872.1 869.2
Average 882.6 879.2 881.0 879.9
Hi-Lo 25.5 19.8 24.0 21.5
FPE-A 13.7 13.6 13.6 13.6
FPE-H 14.0 13.9 14.1 13.9
FPE-L 13.2 13.3 13.3 13.3
ST-Dev 4.3 4.0 3.8 3.7
Pressure Drop CI 497.7 361.9 361.9 407.2
FPE/CI 1.1 1.5 1.5 1.3
PSI-shot 13.8 10.0 10.0 11.3
V1.25, H 0 , S3 7/5/14 V1.25, H 0 , S4 7/7/14

1. Marauder (Totally stock. The only mod I've made was to the lawyer spring).
2. .177
3. Fill Pressure 3000 PSI (Hill Pump)
4. 30 (will do 40 before dropping off, but I only have 3 mags for the moment. I typically refill after I've shot the third mag.)
5. End Pressure: 2500 PSI (after 30 shots). 2300 PSI (after 40 shots)

Need to double check settings as some minor tweaks were made to the hammer spring and throw adjustments. I started at 1.5 CW on the hammer spring (from fully CCW). and about 2.5 (from fully CCW) on stroke. Metering screw is at 2 CCW (this is verified). But I have made some adjustments (probably an additional 1-1.5 turns in on the spring and possibly in a bit more on the stroke - sorry I don't have these figures yet - I started watching the chrony and not recording my adjustments. I am a noob). This tune is getting JSB Exact 10.34gr to move at a peak of 920 FPS (looking like a fairly repeatable 895-920-890 over about 40 shots according to the crony).

Yesterday, I shot a horsefly that landed on my target at 30 yards. Accuracy is outstanding on this rifle!

Hi, I have a 22 cal synrod shooting JSB 18.13 gr. Have no chrony yet. Everything is stock. I get 20 shots before POI starts to drop off bad at 30 yards. Chrony coming next month when I get my bonus check. No idea what FPS is but it hits hard.

.25 cal. Gen II Synthetic Marauder using JSB 25.4 Exact Kings. Fill pressure 2800 psi, 8-9 shots at 880.1 to 877.8 FPS. Re-fill at approx. 2400 psi.

Marauder .22 Gen 1... 0.155 transfer sleeve, 12.5 pound spring, Modified Valve, and Airguns of Arizona Regulator

Tuning: Hammer Spring Pretension x 1 rotation CW, Hammer Stroke x 5 rotations CCW

Fill Pressure 3100 PSI, 1800 PSI at end of string.

Crossman Hollow Points 14.3

40 shots at an average of 940 fps... Max error spread 13 fps... Average 28 Foot Pounds... Some days more than 40 shots, especially if the sun is out.

The air remaining after it drops off the regulator is still capable of 20 more shots averaging 900 fps

All 40 shots create less than a 1" hole in a target at 32 yards from the end of the barrel (measured)

My gun measures 1800 psi on my hill pump when the valve opens to start filling gun.