AEA Possible problem with a Megalodon

What’s up air gun experts? I recently purchased an AEA Megalodon, I have enjoyed the rifle very much. I had no plans to do anything with it but use it as a long distance hole punch. After shooting it a lot I discovered it produces ample power to use it for deer hunting. Even without a moderator and even being a 50 cal the reduced noise when shooting the rifle makes it appealing to me over a powder burner for hunting and possibly even home defense. You wouldn’t go instantly deaf if you had to discharge it inside and so far it holds its air charge reliably. If I fill the tanks on my Megalodon to the max which is 4500 psi, consistently the first time I shoot it produces something like a half power shot. The slug or pellet will hit 6 to 8 inches low and you can just tell by the noise from discharging as well as the sound of the slug impacting being less tells me it’s around half the power it normally produces. My guess currently is the hammer is not striking the valve hard enough to overcome the air pressure enough to allow enough air to produce a full power shot. Assuming that is not incorrect what could be done? As far as I know there is no way to adjust the hammer spring, I would check the manual but it is an AEA product and they apparently don’t want to waste any paper or ink on anything like an instruction manual. Nothing like buying something you know very little about in general , then it arrives and you think they forgot to include the manual, then you start looking and find out they just don’t even bother with any manual. That fact may have caused me to choose a different brand for my first pcp. I didn’t know though and now I own it so I’ve had to ask a lot of questions to get going with it. This is the reason I referred to everyone as air gun experts at the start of this thread. I have found the answer to all my questions so far here on this site. I appreciate all the info so far and would also appreciate any info anyone might be able to share concerning the half power first shot from maxed out air tanks. If I stop filling the rifle at 4100 to 4200 psi I then get a full power shot without fail, so that is what I have been doing. I guess my question is do I need to even worry about it or just stick to 4200 psi ? I’m concerned the issue may become worse over time and I will regret not trying to deal with it now while there is a warranty, assuming they honor it of course. Thanks for reading all that if you made it to the end. Thanks in advance for any advice also.

Jim

p.s.- I’m not filling it inside and then taking it outside where the temp increases causing the air pressure to rise and exceed 4500 psi, I was warned about that happening before I filled it the first time. Just in case someone thinks that might be what’s causing the issue.
 
I shot my .51 Challenger with 4100-4300 fill, it was a sweet starting spot. Didn't notice significant power increase going over that pressure. The most precise and consistent shots were number 2-5 out of 6 slug mag. And it took basically forever for my pump to go over that pressure.

Going to the max pressure still makes sense if you mod your gun with a regulator.
 
I shot my .51 Challenger with 4100-4300 fill, it was a sweet starting spot. Didn't notice significant power increase going over that pressure. The most precise and consistent shots were number 2-5 out of 6 slug mag. And it took basically forever for my pump to go over that pressure.

Going to the max pressure still makes sense if you mod your gun with a regulator.
I didn’t know you could mod a regulator on to a gun that didn’t have one. What you said about shots 2 thur 5 being the best shots, my mags are 8 and 3 thur 6 nearly keyhole consistently from from a lead sled on a table. I can shoot 16 times with the pressure dropping to about 2000 psi, this surprised me, never thought at 50 cal I could squeeze 16 easily lethal shots from those tanks on board the rifle. There is drop , but after you shoot two mags from filled tanks a few times you know how much to hold over for the 2nd mag. All that aside that megalodon would be super sweet if it was regulated probably. I was thinking of getting a regulated rifle in 25 or 30 caliber.
Consistency is always nice when shooting. There are 2 versions of the Meg, a 15 inch barrel and 22 inch barrel. I went with the long one as I didn’t buy it for home defense or a truck gun. I’m going to hunt with it. That’s why that whole valve lock thing was so concerning. I didn’t realize until I got it that the long version has 100 cc’s more air storage with 300cc tanks instead of 250 cc tanks the 15 inch version has got. I really jumped into all this fairly blindly, I looked at that challenger and that single shot Element that can be customized to add a back tank rather than a foldable stock. The guy I was getting it from kept telling me I would be better off with the megalodon. I normally won’t buy something so recently released, I wait for about a year until people find all the flaws and address them. I took a chance because he kept saying the Meg was the best unregulated rifle AEA had released at that time. I don’t know if it is or he is just a decent salesman , either way I ended up with a Megalodon. I have had so much fun figuring it out I don’t think I would change it if I could go do it over. Thank you for replying , you guys on here are the greatest. I appreciate the information very much. Sorry to go on and on , thanks again.

Jim
 
I didn’t know you could mod a regulator on to a gun that didn’t have one. What you said about shots 2 thur 5 being the best shots, my mags are 8 and 3 thur 6 nearly keyhole consistently from from a lead sled on a table. I can shoot 16 times with the pressure dropping to about 2000 psi, this surprised me, never thought at 50 cal I could squeeze 16 easily lethal shots from those tanks on board the rifle. There is drop , but after you shoot two mags from filled tanks a few times you know how much to hold over for the 2nd mag. All that aside that megalodon would be super sweet if it was regulated probably. I was thinking of getting a regulated rifle in 25 or 30 caliber.
Consistency is always nice when shooting. There are 2 versions of the Meg, a 15 inch barrel and 22 inch barrel. I went with the long one as I didn’t buy it for home defense or a truck gun. I’m going to hunt with it. That’s why that whole valve lock thing was so concerning. I didn’t realize until I got it that the long version has 100 cc’s more air storage with 300cc tanks instead of 250 cc tanks the 15 inch version has got. I really jumped into all this fairly blindly, I looked at that challenger and that single shot Element that can be customized to add a back tank rather than a foldable stock. The guy I was getting it from kept telling me I would be better off with the megalodon. I normally won’t buy something so recently released, I wait for about a year until people find all the flaws and address them. I took a chance because he kept saying the Meg was the best unregulated rifle AEA had released at that time. I don’t know if it is or he is just a decent salesman , either way I ended up with a Megalodon. I have had so much fun figuring it out I don’t think I would change it if I could go do it over. Thank you for replying , you guys on here are the greatest. I appreciate the information very much. Sorry to go on and on , thanks again.

Jim
It's a gun. Any gun can be tweaked :)

Yeah, I usually shot two 6 slug mags before going for refill. 500 cc is plenty of air.

Huma-air released a regulator for big bore Challengers. If your bottle is similar to Challenger, you may try it. https://huma-air.com/aea-challenger-big-bore-bullpup-regulator-and-tube-extension-set-by-huma-air/