Hello, I'm wondering if anyone has tried AAO SUPER VALVE with the heavy hammer and magnum spring? If so I'd love to hear about your findings. I have a LSS and an SS in .457. Information on either rifle with the AAO setup would be greatly appreciated. Thanks
Airforce Texan SS AFRICAN AIR ORDINANCE?
- Thread starter EliteAirCustoms
- Start date
Just a friendly note that I have a great deal of experience with the AAO valve, springs and hammer.
Pro: Power gain
Con: Expensive, finicky tuning, and I've experienced three top hat failures. Air is an issue at 4,500psi, using a 7ltr tank filled to 5,000psi you will get one fill on your rifle before the 7ltr tank drops below 4,500 psi.
Please check out my post on "How to tune your rifle" In it you will find an attached spreadsheet with real world numbers on the AAO performance.
Regarding the AAO hammer, spring and performance. Trash the idea of using the magnum hammer due to severe a lack of tunability (heavy hammer is very long and only provided max power). Running the magnum spring with factory hammer works way better.
1. Pre AAO and post AAO yield a FPS gain of roughly 80fps, with greatest gains seen when using heavy slugs.
2. Pre and post AAO spreads went from under 5fps to greater than 10fps.
Pro: Power gain
Con: Expensive, finicky tuning, and I've experienced three top hat failures. Air is an issue at 4,500psi, using a 7ltr tank filled to 5,000psi you will get one fill on your rifle before the 7ltr tank drops below 4,500 psi.
Please check out my post on "How to tune your rifle" In it you will find an attached spreadsheet with real world numbers on the AAO performance.
Regarding the AAO hammer, spring and performance. Trash the idea of using the magnum hammer due to severe a lack of tunability (heavy hammer is very long and only provided max power). Running the magnum spring with factory hammer works way better.
1. Pre AAO and post AAO yield a FPS gain of roughly 80fps, with greatest gains seen when using heavy slugs.
2. Pre and post AAO spreads went from under 5fps to greater than 10fps.
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Check this out.
www.airgunnation.com
Airforce - How to tune your AirForce Texan for max velocity with very little waisted air.
I frequently see airgunners talking about the confusing subject of tuning the Airforce Texan, so I thought it might be helpful, if I shared my process for "How to tune your AirForce Texan for max velocity with very little waisted air." Please understand that tuning your rifle for velocity is not...
www.airgunnation.com Upvote 0
From what I'm seeing in the PDF the max FPS is found in the ranges of 300-310 BAR with the appropriate CF bottle. Going higher to 5k psi would only serve to increase shot count with no gain in FPS past 310 BAR. Correct?
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Basically yes… keeping in mind that the science is weight/pressure specific. Sounds wrong, but lighter slugs go faster at lower pressures in the Texan, and heavy slugs go faster at a higher pressure than their lighter brothers.
1. Heavy slugs create more back pressure, allowing the valve to remain open longer at higher pressures,
2. Lighter slugs creat very little back pressure and no matter how hard the hammer strike, they simply cannot creat enough back pressure to hold the valve open long enough to generate high velocities. The lighter slugs allow the valve to slam closed prematurely.
In my attempts to push 250gr slugs to reliably reach supersonic speeds, I’ve experimented with several different mods, including custome top hats and I am getting close!
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I typically shoot the 365gr High Arc Hunters for deer and the 230gr for hogs/coyote. I have to adjust my scope obviously but I hadn't considered running lower pressures or taking some tension off the hammer spring to make the 230gr go faster. Fantastic info. Let me ask you this....would I be better off to use my Texan SS (stock) at lower pressures with the 230gr and use my LSS with the addition of the AAO valve and magnum spring for the 365gr? I suppose an easier way to ask it is...will I just be wasting money with a second AAO valve and spring on the lighter slugs?
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Forgive my ignorance. Just a little confused about whether or not to add the expensive AAO valve to the rifle I plan to shoot lighter slugs. I suppose in theory with the AAO valve that even though the lighter slugs allowing the valve to close sooner, the increased output of the super valve in that window would equate increased velocity? You're correct, there's a science behind all of it. So, I'm struggling a little. My apologies.
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Look at it this way and then make your decision. There is some gain in velocity when the rifle has an AAO Valve and it’s tuned properly…. but the gain is small and you can easily drop a 400lb hog with a stock Texan shooting 230gr slugs. Hell my buddy dropped a 250lb hog and a Ram the same day using his .357 FX and 100gr Mr. HP slugs.
If your rifle is tuned for heavy slugs and you drop in lighter slugs and fail to retune the rifle it will significantly underperform. Having two rifles dedicated to a specific slug has many advantages, mostly in the ability to properly tune for max velocity and very little wasted air and not need to worry about retuning.
If your rifle is tuned for heavy slugs and you drop in lighter slugs and fail to retune the rifle it will significantly underperform. Having two rifles dedicated to a specific slug has many advantages, mostly in the ability to properly tune for max velocity and very little wasted air and not need to worry about retuning.
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Hey, finally got my valve, hammer and spring in. I got it installed but haven't shot it yet. I'm a little concerned about the install. It sounds gravely when I cock it. I expected it to be harder to cock. That Magnum spring is crazy long. I'm thinking what happened is as I was threading the spring tension adjuster back in it was winding that spring a little an that is what I'm hearing. Did you notice the spring needing to settle in after your install? If it's something that will auto correct itself after I fire it a few times I'm going to go ahead and get it tuned and sighted in. But, if you think it's something wrong then I'd appreciate your thoughts before I proceed. Thanks for your time and expertise.
Kind regards, Brett
Kind regards, Brett
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I hope its not your auto saftey messing up..I had mine fail twice before deleting it myself...
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I removed mine right from the start. It was making a ticking sound as I put the power wheel back in. I assumed it was the compression of the spring. The sound is in the carrier tube. The trigger group sounds fine. Safety works and I can decock it.
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The factory spring was much shorter and had a heavy coat of grease on it. In the link Jeremy sent for installation video they didn't re-grease the new spring. Maybe I should have? It is supposed to be considerably harder to cock, yes?
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Assembly error likely. The AAO set up should ne smooth, never gritty and cocking force will roughly double over stock. Also, I recommend using the stock hammer with the magnum spring. The heavy hammer is impossible to tune, it is designed for big massive slugs and no matter what you do, it will only provide one power level… max.
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Now that's funny! Jeremy is instructing you to set the spring tension to minimum for max power... LOL
He just confirmed what I told you... there is no ability to tune the rifle with that ridiculous hammer, the massive length creates excessive spring pressure at the power wheels minimum tension setting and the massive weight makes the rifle feel like an old black powder flint lock, where you pull the trigger and two seconds later the projectile leaves the barrel, ok... slight exaggeration, but I'm telling you the factory hammer will give you the same velocities as the heavy hammer, reduce the lock time and enable you to tune the rifle properly, which should gain you anywhere one or two extra shots before velocity drops off significantly. I wont mention it again... don't want you to think I'm being pushy and I'm sure that you will eventually figure this out on your own.
Note: Regarding a rifle that feels gritty when cocking. If you can safely dry fire the rifle, try this before you head out for testing, I hope I am wrong, but I have a feeling that after it's fired you may experience a problem re-cocking the rifle. Just give it a try and let me know if it functions ok.
He just confirmed what I told you... there is no ability to tune the rifle with that ridiculous hammer, the massive length creates excessive spring pressure at the power wheels minimum tension setting and the massive weight makes the rifle feel like an old black powder flint lock, where you pull the trigger and two seconds later the projectile leaves the barrel, ok... slight exaggeration, but I'm telling you the factory hammer will give you the same velocities as the heavy hammer, reduce the lock time and enable you to tune the rifle properly, which should gain you anywhere one or two extra shots before velocity drops off significantly. I wont mention it again... don't want you to think I'm being pushy and I'm sure that you will eventually figure this out on your own.
Note: Regarding a rifle that feels gritty when cocking. If you can safely dry fire the rifle, try this before you head out for testing, I hope I am wrong, but I have a feeling that after it's fired you may experience a problem re-cocking the rifle. Just give it a try and let me know if it functions ok.
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So, I tried the AAO valve setup on the Texan SS. Jeremy sent me a video of a Texas carbine (same gun just unmoderated) shooting 338 gr slugs at 653 FPE. I've been working on this setup for a day and a half (HARD) now and haven't achieved anywhere near that. I'm shooting 365 gr High Arc Hunters. He discouraged me from Neilson slugs because he says the lead is too hard and will under preform. He's had me doing all kinds of modifications to the valve to squeeze out some power. He wants a 4,750 psi fill pressure. He had me file 1.5mm off the supplied top hat bumper. Work through a wide range on the hammer spring tension wheel. It's just not preforming. I've put 3.5 bags of slugs down range and I'm at best, 25 FPE over stock with the 250 bar carbon bottle. I was getting 515 with the 250 bar bottle and around 535 with a 300 bar bottle out of the tx2 valve, factory hammer and spring. With the AAO valve, heavy hammer, and magnum spring I'm getting 558 FPE. That's not enough to warrant the $700 price tag for those parts. I did try the factory hammer with the magnum spring and your right.....Same results, just coming from the other direction with the power wheel at max by comparison to his barely visible approach. The MOAV valve design is pretty strait forward. I can see the shot consistency is better because of the added plenum but you remove the top hat without pressure on the bottle and just a threaded rod with a rubber stopper is all that's inside. I don't suppose there needs to be anything else. I can see that most of the "science" is the quality and integrity of a valve that can handle the higher fill pressures. So, I get it. I just don't know if I can $550 for the valve "get IT", for no more increase than I've experienced thus far.
As to the gritty sound....the magnum spring looks to be nearly identical in diameter to the factory spring but it is much longer. I get that...a beefier, longer, stouter spring increases hammer strike regardless of hammer weight. But, once the spring is compacted by the hammer tension adjuster, it increased in diameter and actually rubs the two small screws that connect the cocking lever to the carrier tube. The thread surface and thread count of the carrier tube are so few that I couldn't bring myself to file them down any further. So, the spring coils rubbing against those 2 screws are the cause of the sound. Not the "German Piano Wire."
I'm at a loss for what to do. I wanted my SS to be comparable to my semi stock LSS, but I'm a minimum of 100 FPE short. I asked about returning it for a replacement or refund but that's where our email dialogue ended. I'm not implying that its anyone's fault. The design and concept seem sound. Not to mention I see lots of great result videos on YouTube. But, for some reason undenounced to me, mine is barely more powerful than the tx2 valve with a 300bar fill. I don't know all the specs of the tx2. Perhaps a 300 bar fill will prematurely fail at that pressure. However, I've sent hundreds of slugs down range without incident to date.
Just about ready to pull my hair out and buy a regular full size Texan to keep the length down and call it a wrap. Or, a full length Bushbuck. I love the moderator of the LSS and SS but the LSS is ridiculous to hunt out of a treestand with. The SS is accommodating in length but I'm after 650 FPE. All I want is what the supplied video illustrated. You'd think for $700 it would be a done deal. Maybe it's just me and my experience level. However, I've jumped through all the hoops I plan to with the remove/replace/modify modified parts to be done with it. If I'm doing/not doing something wrong please let me know. Any advice I can get is greatly appreciated. TTYL, thanks
As to the gritty sound....the magnum spring looks to be nearly identical in diameter to the factory spring but it is much longer. I get that...a beefier, longer, stouter spring increases hammer strike regardless of hammer weight. But, once the spring is compacted by the hammer tension adjuster, it increased in diameter and actually rubs the two small screws that connect the cocking lever to the carrier tube. The thread surface and thread count of the carrier tube are so few that I couldn't bring myself to file them down any further. So, the spring coils rubbing against those 2 screws are the cause of the sound. Not the "German Piano Wire."
I'm at a loss for what to do. I wanted my SS to be comparable to my semi stock LSS, but I'm a minimum of 100 FPE short. I asked about returning it for a replacement or refund but that's where our email dialogue ended. I'm not implying that its anyone's fault. The design and concept seem sound. Not to mention I see lots of great result videos on YouTube. But, for some reason undenounced to me, mine is barely more powerful than the tx2 valve with a 300bar fill. I don't know all the specs of the tx2. Perhaps a 300 bar fill will prematurely fail at that pressure. However, I've sent hundreds of slugs down range without incident to date.
Just about ready to pull my hair out and buy a regular full size Texan to keep the length down and call it a wrap. Or, a full length Bushbuck. I love the moderator of the LSS and SS but the LSS is ridiculous to hunt out of a treestand with. The SS is accommodating in length but I'm after 650 FPE. All I want is what the supplied video illustrated. You'd think for $700 it would be a done deal. Maybe it's just me and my experience level. However, I've jumped through all the hoops I plan to with the remove/replace/modify modified parts to be done with it. If I'm doing/not doing something wrong please let me know. Any advice I can get is greatly appreciated. TTYL, thanks
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I forgot to mention he had me remove the barrel completely and machine off 3mm of the carrier tray before installing the valve. And, I'm glad he did. It saved me from having potential top hat failure from contacting the loading tray. I want to be clear that I'm in no way discrediting Jeremy, or African Air Ordinance as a company. I think it's a great place for high end, high quality, modified parts. He's been very accommodating with his responses and customer service care. Maybe I just got a lemon. I expect to hear back from him tomorrow with the time difference between us and South Africa. My only complaint, and I use complaint very casually, is he had me do quite a bit of fine tuning and modifications on the new valve for minimal increases. When you're 100 FPE off the potential mark (per his estimated numbers via the video link) it seems redundant to fine tune without addressing the elephant in the room. I'll be back tomorrow with an update. Thanks to all of the AGN family for your feedback.
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