FX .30 Panthera H/C build advice

Hi Guys, I recently purchased an FX Panthera HC in .30. Got the 10 for 10 from Pyramyd & upon reading it they ended up using 44 grain jsbs & got about an average of 67 FPE of energy. (They had the reg set @ 100 bar)..Since then I decided to turn up the regulator to around 140 then 150 & am now getting around 85-90 FPE with 50 gr's sligs hitting @ around 880-900fps... The gun seems to like slugs better than it does pellets even though it does have a small barrel I've added an impulse 1350 moderator with an extra cone insert as well as the non tapered extension piece so it lines up directly with the barrel flush from A of A. Getting about a clip to a clip and a half with the regulator @ 150.. have a couple questions about using a bigger bottle on the front. I don't want to make the gun too heavy but I would like some more air on hand while using the foldable stock option that I use. Any suggestions would help me as to a 480cc, 580cc or even 700cc bottle? Also I know that it says that 250bar is max on these guns.. but I've heard of people going up to 300bar with the new FX bottles.. (just don't know how safe that is!) also would like to know if I NEED the tungsten hammer and heavier spring kit to get the velocities/power that were advertised for this particular gun which the energy report from FX is 107 FPE. So I'm looking for another 20 or so FPE... Also I've never have installed such item/s and then wondering how hot it would be to install. I'll post a couple pictures and having a hard time downloading my chronograph measurements to my phone for some reason but I can come up with the shot string as well hopefully. Basically what I'm looking for is obviously high as shot count and highest power for this will be used for dispatching coyotes. I currently have just a Trijcon Mro Red Dot the top of it but will be soon running a ffp Vortex 3-15X50 on it with high rings. Then we'll be using a 90° angle Weaver picatinny for the Red Dot just in case something is closer. All/most hunting that will be done will be (150 yards max)...Any questions comments and concerns I greatly appreciated. Goal is to get This rifle gets rather long really quick once adding a moderator in folding out the stock all the way goes from 26 inches I believe folded without moderator to 42 or so inches completely folded out all the way out and with moderator on. But I will tell you this this particular moderator is stupid quiet! I also like it because it's made in the USA unlike some other companies. Thanks, Surefire!

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I bought the same gun earlier this year. Build out was simple. I went with a Sonus moderator. I have a couple IA moderators and the Sonus just work better for me. I changed the 300cc bottle out for a 480cc.
I topped it off with an Element Helix 4 x 16 IR scope.
I am shooting JSB Hades at 905 fps and the gun is pretty much tapped out at that level. Still shooting just under 80 fpe but very accurate. I tried pushing a bit more and the gun got a little harsh sounding and the shot cycle was not pleasant.
I am contemplating a short pattern bottom rail extension but am not too sure I want to add weight to the gun. I shoot it off shooting sticks when I am out in the field.
I love the gun. It packs a good punch and is pretty easy for carrying in the field.

My humble opinion is that even with the tungsten hammer and different springs that short barrel will prevent you from getting anymore out of it than you are. I called Utah Air guns and they told me 900 fps was aabout ax with the 44.75 gr pellets. You add that hammer and springs and you are just inviting a gun that is not near as pleasant to shoot and you will be hammering the system pretty hard.
I shot a fairly large badger with mine earlier this year. Little over 60 yards with a Hades pellet. Shot him through the shoulder and he took two maybe three steps and was dead. In my experience badgers are every bit as tough as a coyote. I am happy with my power where it is for coyotes out to 75 yards
 
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I bought the same gun earlier this year. Build out was simple. I went with a Sonus moderator. I have a couple IA moderators and the Sonus just work better for me. I changed the 300cc bottle out for a 480cc.
I topped it off with an Element Helix 4 x 16 IR scope.
I am shooting JSB Hades at 905 fps and the gun is pretty much tapped out at that level. Still shooting just under 80 fpe but very accurate. I tried pushing a bit more and the gun got a little harsh sounding and the shot cycle was not pleasant.
I am contemplating a short pattern bottom rail extension but am not too sure I want to add weight to the gun. I shoot it off shooting sticks when I am out in the field.
I love the gun. It packs a good punch and is pretty easy for carrying in the field.

My humble opinion is that even with the tungsten hammer and different springs that short barrel will prevent you from getting anymore out of it than you are. I called Utah Air guns and they told me 900 fps was aabout ax with the 44.75 gr pellets. You add that hammer and springs and you are just inviting a gun that is not near as pleasant to shoot and you will be hammering the system pretty hard.
I shot a fairly large badger with mine earlier this year. Little over 60 yards with a Hades pellet. Shot him through the shoulder and he took two maybe three steps and was dead. In my experience badgers are every bit as tough as a coyote. I am happy with my power where it is for coyotes out to 75 yards
Thank you for your response! Was shooting jsb 50.15gn knockouts at about 885 FPS yesterday after I put this post up. According to Pyramyd's ballistic calculator the FPE was 87.24. that was the top charter most were in the 875+FPS realm..(13 shots in the clip). Even @150bar on the regulator I believe I could have got another perhaps full clip out of it. So I guess I am pretty much maxed out. Gun was shooting excellent! Did not feel any kind of crazy recoil or any kind of extra air hiss... That being said., you told me you went up to a 480cc bottle correct? Wondering if it's worth it for me to get that particular one or perhaps even a 580 CC.. I would honestly be happy if I could get four full clips. Not sure if that's asking too much with the 480. Perhaps the 580 would be significant enough of volume to achieve that goal... Also in my question referring to the 300 bar FX tanks. Will our guns take 300 Bar without damaging anything? (In the bottle not the regulator). After reading that you took out what you took out running around 10 FPE less than I. That makes me feel confident enough to be able to take out coyotes with a nice clean headshot especially within 150 yards. What are your thoughts on my question about shot count? For I would love to just go out in the field with one bottle connected without tethering or carrying along on another 300cc bottle that I already have. (Time to disconnect old and connect new bottle & minimalistic carrying). I obviously don't want to run the twin bottle setup unless there was a way that I could put two 300s in the front. For I like the feel of the rifle that it being heavier in the front in the little lighter in the back ..reminiscent of what I'm used to (AR-10 w/16in barrel). I also have a saber tactical top rail. (Not shown in the pictures)Yet even opening up the six bottom screws I'm still only able to put on a 300cc bottle. I believe with a little modification i.e; cutting / drilling out the rest of it where Clarence will not be an issue by putting a bigger bottle, it will allow me to also have the top rail for I was going to put my IR laser a top it... The Saber Tactical top rail is made out of aluminum of course so the cutting should not be that difficult. (Currently running side adapter twin picatinny rails right underneath the barrel). Set-up is ok for now.. but I would rather have the top rail connected instead of what I'm running now. But I do not have a full on Machinist tool set ie; bridgeport, lathe and other machines that would make things a lot easier for me. But I do have other things such as a nice laser-guided drill press as well as a couple different sets of end Mill bits as well as other tools that I could use to make this particular top rail work in case I wanted to use it with a bigger bottle. So I guess you pretty much answered my question as far as what penetration in FPE it would take to ethically kill a coyote. As far as power combo meaning the heavier hammer spring and tungsten hammer weight etc.. you're telling me it's not a good idea or worth messing with that? Also was thinking about a superior slug liner ... Not sure if that will give me proper twist rate for all shooting of different pellets/lugs. For I don't want it to be a slug only gun unless I am reaching powers up to at least 100-115FPE+ Plus! I thank you for your time & input. Sincerely Surefire!

I also did a shot string with the FX 44.8gn pellets and got about 83 or so FPE, which is only 4 FPE less than the 50gn Knockout's that we're @ 87FPE... Which isn't a spectacular jump and power but was a little more power. (Plus they're slugs) I'll be experimenting with more different kinds of ammo to see what will be proper result in me choosing of course after installing the scope. Come to find out it's actually a 3-16X44 instead of the 3-15x50 that I stated in my original post. I'll post a couple more pictures to show you the setup. Please feel free to help me out in regards to what bottle to go with next and as far as the 300 bar question that I had as well. Before I do not want to build something around parameters that I either cannot use or will be damaging too my gun. Thanks again, Happy holidays & Hunting!
-SF ....hope I didn't go to high up with the rings, thinking now I might have gotten away with mediums 😂 ... Also I ended up going with the Panthera Hunter compact version of the bottom rail. I'm wondering if I could have put in a larger bottom rail on that normally fits the regular Panthera, I just didn't want to order the wrong part at the time. But if the screws line up I definitely would like to go with a longer bottom real as well so I don't have to get a Saber Tactical 60 mm bottle clamp just to attach a nice Troy industries ranger style vertical foregrip. I also went with a Wilson combat sports rare buttstock which sits beautifully in combination with what that I have! But like I said I would love the extra real space as well as the bigger bottle. Thanks again! Oh one more thing I forgot to mention. I ended up loading some Hunter's choice 80 grain slugs.. got low to mid 700's in FPE.. they chambered very hard and was definitely too heavy of a slug to use but I just wanted to experiment a bit. This gun is definitely not set up for heavy slugs at the moment and even with the heavy slug barrel liner, I don't see me getting much extra power out of that particular setup but who knows as you said it's a short barrel to begin with and even with those modifications I don't expect to be shooting those particular slugs that fast.. even though if we look at the specs from FX they state that they were using a 68. something grain slug to achieve the 117 FPE. Perhaps they forgot to mention that they also put a heavy slug barrel liner in as well as a heavier spring and tungsten hammer & valve setup... Perhaps they should have prior to selling this gun. Because perhaps if they did I might have went with something else. But I ended up picking this thing up for around $1,400 bucks brand new! & So far am impressed with the way it shoots Feels and handles! Just wished the power that they advertised was what I was getting right out of the box! Even if I had to mess with the regulated settings it's still would not have been a problem. But when I first got it the right was set to around 100ish and the shot string came back at 67 FPE Max on the 10 for 10! In my head I was like that's exactly what the 25 Cal stated for power! And if that was the case I would have went with the 25 caliber for it's a bit shorter and still has the bigger 120cc plenum. I've still yet to see any caliber change kits as well ... Not sure if you have at all?

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My gun is set up for coyotes hunting and as my current truck gun. So my priorities are in order; accuracy, power, light weight and easy to carry.
The gun is unquestionably accurate with either JSB Hades or the FX 44.whatever pellets and the RMR (Hybrid slugs). The power is enough to take out a coyote and I have no delusions of shooting one in the head at any distance. I am calling them and when they come in they are on alert already. chance of that head moving are too high to risk it. Also I shoot off shooting sticks because I don’t want to carry around a tripod or any other such heavy and awkward support.
Therefore, it is going to be a pellet through the lungs and or heart. I am trying to keep the weight and bulk of the gun as low as possible because hiking the hills around here are part of the process. Last year I tried the 357 Rattler and it was just too big and heavy for hiking around.
 
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My gun is set up for coyotes hunting and as my current truck gun. So my priorities are in order; accuracy, power, light weight and easy to carry.
The gun is unquestionably accurate with either JSB Hades or the FX 44.whatever pellets and the RMR (Hybrid slugs). The power is enough to take out a coyote and I have no delusions of shooting one in the head at any distance. I am calling them and when they come in they are on alert already. chance of that head moving are too high to risk it. Also I shoot off shooting sticks because I don’t want to carry around a tripod or any other such heavy and awkward support.
Therefore, it is going to be a pellet through the lungs and or heart. I am trying to keep the weight and bulk of the gun as low as possible because hiking the hills around here are part of the process. Last year I tried the 357 Rattler and it was just too big and heavy for hiking around.
Oh wow that's crazy because I actually have a LCS sk19 in 30 and although it's great in every way like you said it is rather bulky for being a truck on and or a walk-in hunt! How many clips are you getting out of your 480 bottle? For I'm looking into something bigger than my 300cc. Would like four clips as I said prior but is that asking too much out of a 480? Perhaps a 580 would be best for that.. and then there's a 700 CC of course but that would make the gun a bit more heavier. Even though it should match right up nice with the air impulse 1350 with an added insert to reduce muzzle report even more. As well as the bore match instead of the taper connection that it came with. I'm getting 78 decibels after including the extra insert as well as the flush adapter to the barrel. Without it it was registering around 150 but again I'm using an app so numbers can't be verified as 100% accurate. As far as getting a FX heavy slug liner with a 1-16 twist I haven't been able to find one for our 395in barrel... I know you said before that doing the hammer spring/tungsten him away and pin probe would be kind of maxing out our system. But I also see that the gun is only supposed to take 250 Bar max as far as fill up and bottles are concerned. This may be a stupid question but if I were to remove my 300cc 250 bar and replace it with a 300cc, 480cc, or 580 CC bottle that's capable of 300 bar would I be able to fill it up to 300 bar without any issues? Or would that put too much pressure and ruin the guns and internals? Just figured I'd ask seeing how you already told me that messing around with the heavier hammer spring/weight and whatnot would be putting extra pressure that is not needed.. but with a 300 bar bottle and filled to 300 bar am I inviting the same kind of issues as you stated with the kit that I mentioned? Thanks again - Surefire
 
I can get 2 1/2 mags comfortably. When I go coyotes hunting or am in my truck it is not a high volume shot situation. Shot count past the point I am at is not a consideration.
Sounds like the 480cc bottle will be a perfect set-up for me as well than. If u don't mind me asking what company did u get you're 480 from? FX or a generic Amazon or eBay company? (I have Tusing or whatever 480cc on my LCS-SK19) and hasn't had no problems whatsoever with it for a long time, (knock on wood). In obviously would have to get an ethics adapter though if I run one of those bottles.. my only concern would be clearance height and length i.e; depth and diameter of course. But other than that I'm definitely up for saving a couple pennies if I can. Oh and have you ever tried one of the other nor mags for our particular gun? I think they have a squarish one perhaps made by John and also a single shot loader I saw on eBay.. I think it would be a nice addition especially for the single shot loader. Also what do you think about my 300 box question? Will that put too much pressure on the internals? Or am I already answering my own question.. thanks again - SF