Accuracy problems. What do I do?

Forums PCP Airguns Accuracy problems. What do I do?

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    AirgunBill
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    Kyler if you get the dead head fitting which is a cheap way to check your fill tanks pressure this is how you would use the fitting. The dead head is a closed end fitting on one side and an male foster fitting on the other. You insert the male foster into the female foster hose connected to your fill tank. Then close the bleeder valve on your tank and open up the main tank valve. You will then see the existing pressure of your fill tank. Then  shut off the main valve and open up the bleeder valve again to depressurize the hose. The only air you loose in checking you fill tanks pressure is that in the filler hose. Hey guys if I am wrong on this or not explaining it well chime in. I want really want to get Kyler headed in the right direction. Bill

    A youtube video. A video is worth a million words?

    http://www.youtube.com/watch?v=n28DolL7vX4

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    30cal
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    Sounds right to me Bill.

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    kyler2643
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    Airgunbill and 30cal thanks so much! Ill be sure to get me a deadhead. I appreciate you guys helping me! Ill let you know how the system works out!

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    Deleted Account

    Your tank and gun are probably fine. I’ll bet who ever is filling your tank is only filling it to 150 bar.

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    AirgunBill
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    Kyler if I may give you a little more information when you go to get your tank filled and expected fills to get off your 75 cu/ft tank. Most times when I drop my tank off for filling I usually pick it up an hour of so later. They rarely get the full 4500 psi fill, partly because the air cools down after filling. In that case the fill level is about 4200 to 4350 psi.. When I can leave  it there and pick it up the next day they can get the 4500 psi I guess since they can top off the tank. Since it is a 50 mile round trip for me and it costs me gas and time I usually pick up the tank after the hour or so time frame. The next thing to know is how many fills you can get off your 4500 to 4200 psi fill. Pyramyd Air has a tank fill calculator on there site to help figure out the amount of rifle fills you will get from Your CF tank.Once again having a chronograph to figure out your usable fill range will help you in these calculations. The calculator is somewhat hidden on the site but you can find it under any PCP rifle description by selecting the ‘PCP Hookup’ tab. Then click on highlighted ‘Tank Fill Calculator’ on the left side of the page. The chart will pop up and you fill in the info about your rifle set-up. You will also have to find a bar to psi conversion  calculator to enter the psi information. I did a calculation for you with the best information I know about your rifle. It appears you will get in the range of 18 to 22 fills off your 75 cu/ft 4500 psi tank depending on how well they do the fill. Bill

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    kyler2643
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    Thanks airgunBill. Could this be the reason why I have to sight my rifle in every time I shoot it? I don’t understand that. 

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    AZBOBCAT
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    Yes when your pressure is low your velocity will be slow causing your shots to drop. Let’s say at a full fill you are shooting 900 fps and at 100 bar you are shooting 800 fps your shot could be dropping a couple inches at 50yds

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    AZBOBCAT
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    If you are starting to shoot on the downward part of your string every shot will just get slower and slower. Look at a shot string that people have posted and you will see that it usually starts out at say 900 for a couple shots and starts to creep upward to say 920 for a few shots then starts to gradually come back to 900 and then slowly go below 900 that area from 900 to 900 again is the sweet spot where you want to be shooting then refill and shoot again. What you are probably doing is filling to just after the sweet spot and all your shots just continue to drop off in velocity quickly.

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    kyler2643
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    Makes sense but it’s my left and right that seems to be off the most. Every time I shoot it it just goes off to eather side. That’s what I have to keep zeroing. I hope it’s not the scope :( it was $300. And I’ve kept good care of my gun and optic. Not a scratch on eather of them.

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    AirgunBill
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    Kyler your rifle is designed to work over a pressure range. Your rifle has a regulator to keep shots close in fps over the usable pressure range. If you shoot the rifle after it comes off the regulator fps will drop off rapidly and you will not get accuracy. Your rifle is designed to be filled to 220 bar and probably only shot down to say 150 bar. That is why you need a chronograph to track velocity from a full fill till the rifle comes off the regulator and velocity drops. At that point you fill your rifle and note where the fill gauge pointer slows down showing how low your pressure level dropped to, that will also show where your regulator is set to. I don’t know if there is a good video on you tube to watch on this but starting reading a lot of posts about rifle tuning and shot strings to get an idea of whats going on. Bill

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    sgtskinny
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    After sorting out the pressure/gauge issue then look at other possibilities That L/R POI shift could potentially be the scope, the nice thing about PCPs is no appreciable recoil, so you can put any cheap scope w/ short parallax on it to verify. Check all action and stock screws. I’m not familiar with your platform, but the barrel must be attached to the action by some means, make sure it is secure at the anchor point.

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