Other Truth behind Macavity Arms Prototype Airgun

Rvaughn, great post, and spot on, nice job with the pictures too. I will be following this post, as I just started working on mine.

Having been shooting a Brocock with a 17" barrel and a reg @ 150b for 875fps w/18.13gr, and then shooting this with an 18" barrel and the reg @ 110b same pellet 865fps; I can say that this gun is too loud. The numbers may look great, but it is definitely wasting air. I am going to try a higher pressure and keep the speed about the same and see if I can change the dynamic. Hopefully I can do this without a spring change. I will work on groups only after I get it to shut up. Seems like some are shooting better than others, but for me, they have to be quiet first, or I''m just out shooting a rimfire.
 
Rvaughn, great post, and spot on, nice job with the pictures too. I will be following this post, as I just started working on mine.

Having been shooting a Brocock with a 17" barrel and a reg @ 150b for 875fps w/18.13gr, and then shooting this with an 18" barrel and the reg @ 110b same pellet 865fps; I can say that this gun is too loud. The numbers may look great, but it is definitely wasting air. I am going to try a higher pressure and keep the speed about the same and see if I can change the dynamic. Hopefully I can do this without a spring change. I will work on groups only after I get it to shut up. Seems like some are shooting better than others, but for me, they have to be quiet first, or I''m just out shooting a rimfire.

I will have to definitely give the jsb 18s a solid try in this rifle since according to the manufacturer that’s what it’s supposed to shoot.. just don’t have any on hand at the moment.

Yesterday I pulled the reg out and made a quarter turn counter clockwise from factory setting.. I have no idea as to what the pressure is at now but it’s supposed to be 1600psi according to MA’s website, so maybe 2000psi 🤷🏻‍♂️ I can’t say for certain but I wouldn’t imagine it cranked up too much..
Anywho… I turned the hammer spring in about half of its adjustable range and was slinging a 25.4 JSB at 830fps for almost 39fpe!!
With only a 17” barrel to boot!
This little thing appears it may turn out to be a powerhouse if needed 😎

Couldn’t do any accuracy testing though since I only had 2 pellets left but I’ll have to get some ordered up give em a fighting chance before too long.

I’ll be looking forward to seeing your results once you get done as well sir!
 
I will have to definitely give the jsb 18s a solid try in this rifle since according to the manufacturer that’s what it’s supposed to shoot.. just don’t have any on hand at the moment.

Yesterday I pulled the reg out and made a quarter turn counter clockwise from factory setting.. I have no idea as to what the pressure is at now but it’s supposed to be 1600psi according to MA’s website, so maybe 2000psi 🤷🏻‍♂️ I can’t say for certain but I wouldn’t imagine it cranked up too much..
Anywho… I turned the hammer spring in about half of its adjustable range and was slinging a 25.4 JSB at 830fps for almost 39fpe!!
With only a 17” barrel to boot!
This little thing appears it may turn out to be a powerhouse if needed 😎

Couldn’t do any accuracy testing though since I only had 2 pellets left but I’ll have to get some ordered up give em a fighting chance before too long.

I’ll be looking forward to seeing your results once you get done as well sir!
I shot mine down, and would say that the reg was at 1600psi and by the shots I got using 500psi of air, it was on track to get 60 shots. It's still to loud though. I am looking to make a SSS for it, take the trigger group apart and replace that first stage (Lawyer) spring, and turn up the reg. The only thing that concerns me is the barrel retention system. There is no way you can run this gun without that front barrel band in place for any length of time. I wouldn't attempt it at all, having just taken it apart. Iam shocked that you managed the groups that you did. A real project piece.
 
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I shot mine down, and would say that the reg was at 1600psi and by the shots I got using 500psi of air, it was on track to get 60 shots. It's still to loud though. I am looking to make a SSS for it, take the trigger group apart and replace that first stage (Lawyer) spring, and turn up the reg. The only thing that concerns me is the barrel retention system. There is no way you can run this gun without that front barrel band in place for any length of time. I wouldn't attempt it at all, having just taken it apart. Iam shocked that you managed the groups that you did. A real project piece.

To your point on the barrel retention system, I believe I know what caused your concern because the first time I had mine apart and was re-threading the barrel in by hand I got it snugged up as far as I could by hand and noticed there was a huge amount of slop up and down with the barrel.
That had me concerned as well!
But after I thought about for a sec I figured out the correct method for reinstalling the barrel.
So 1st thread the barrel in til its snug and with the grub screw removed, peer thru the hole for grub and line up divot for grub screw.. then install grub and tighten it.
Next … take the threaded end piece that tensions the shroud and install it on muzzle of barrel til it bottoms out on threads.
Now you can use an adjustable wrench on the tension nut to snug the barrel up the rest of the way in the breech
You will then notice that all play has been removed and barrel is plenty secure enough to run un-shrouded or un-banded.. whichever you prefer.
Hope this helps!
 
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Yeah, I understand it just fine. I am still leary of it. Before tightening up the shroud, just the barrel in the threads moves quite a bit. That's asking alot of the shroud to me. I know the grub is just holding the spin and the threads are doing the work, but still. We shall see. The tension is going to have an effect on accuracy, how big, we'll see. It will be interesting to see what happens in the hot sun with thermal expansion. I am use to the beautifully over-built AAA barrel system, everything else seems (is) less, but for the money, I am super impressed with the build of this gun; especially considering it is a first attempt.

The barrel is certainly stiff enough, no soda straw, that's for sure. This gun is no SPA either, everything was tight and in place, my P15 receiver block and trigger were nicely machined too, it's just that the gun was assembled loose. I decided against changing springs in the trigger. I adjusted out the play, it is at 24oz so what's the point. It feels lighter than it actually is. The SPA trigger in my P15 is far superior to this setup and that gun is very close in price.

You turned your reg up a quarter turn (3 hours on the clock) I turned mine 4 hours. The actual starting length was 2.048" doing 1600psi, and I changed it to 2.060". I have yet to figure out the change in setting. I will say, that unlike everybody else, I wish they had put the pressure guage on the end and used a probe. That way adjusting the reg would have been super easy to do with just undoing the grub screws on the barrel band and unscrewing the tube. Of course, they didn't care because they always planned for the final version to be externally adjustable anyway.

The one feature that I am sure that I absolutely hate is the o-ring in the barrel, and it's deep, like 3/16" in, and tiny. It will be a real pain to replace I'm sure. They should have put the o-ring on the probe.

I am waiting on a scope and different stock and grip to show up, and then I will get to accuracy testing. I did fire off some shots to check the speed and set it to 880fps. It isn't any louder, might even be a little quieter.

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My regulator adjustment, which I thought was pretty big, didn't seem to do much. Shooting it down, it looked like it is now at 1700-1750psi, about a 10bar difference, and the psi used per shot is still 33.3. That still works out to about 60 shots per fill, so no efficency was lost. I am running twin springs on the hammer so I don't know if that's helping these efficiencies, or if just upping the pressure didn't effect them. I am going to take my magazines apart and plug the first hole with JB Weld so that I know when I am empty, and stop shooting on an empty chamber.
 
A couple more points I have found along the way. On spring loaded magazines, like the Marauder, there is three holes for you to choose the right tension, or to re-tension, your magazine; this magazine only has one hole in the body. I was hoping to back off the tension a small amount, but no dice. I also don't think that I can plug the first chamber with JB Weld in a reliable enough fasion that I would trust doing so. The chambers are very open and thin and I would think that it would have to be designed in, maybe CARM will drop a round and do that when he he makes magazines for this gun.

I had not originally noticed but the hole in the stock, beneath the magazine on both sides, is a window to view if your gun is cocked and the hammer back, or not. Clever, but i will probably get some plugs to keep debris out.

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I agree. JTS are also. I'm here for it. Just like my Taipan and Evol. Much better than slip fit and grub screws
It is not the same in the rigidity department has the Taipan or the Evol. It relies a lot on it's very thick shroud and the extremely thick barrel band to complete the ensemble. The Taipan needs nothing else, and the Evol is so good that Dana Webb threw it off a cliff, put a significant dent in the shroud, and it still shot well. They, of course, are 3-5x more expensive and you get what you pay for. However, the MA2 all together, does seem to be extremely solid, and clever design,but only time will tell how it holds up. I don't want, or mean, to detract from how impressive it is, at its price point, but people shouldn't be comparing this gun to top tier designs. Compared to the other sub-$750 airguns out there, the design choices and compromises that Macavity took does make it a different choice, and a solid one. People wanting to use their AR furniture are going to love it! To that point, I will mention something else that I haven't seen mentioned. When you buy an Ergo grip it comes with a standard screw, the MA2 doesn't use that size, it uses a much smaller 10-32. Just something to be aware of.
 
It is not the same in the rigidity department has the Taipan or the Evol. It relies a lot on it's very thick shroud and the extremely thick barrel band to complete the ensemble. The Taipan needs nothing else, and the Evol is so good that Dana Webb threw it off a cliff, put a significant dent in the shroud, and it still shot well. They, of course, are 3-5x more expensive and you get what you pay for. However, the MA2 all together, does seem to be extremely solid, and clever design,but only time will tell how it holds up. I don't want, or mean, to detract from how impressive it is, at its price point, but people shouldn't be comparing this gun to top tier designs. Compared to the other sub-$750 airguns out there, the design choices and compromises that Macavity took does make it a different choice, and a solid one. People wanting to use their AR furniture are going to love it! To that point, I will mention something else that I haven't seen mentioned. When you buy an Ergo grip it comes with a standard screw, the MA2 doesn't use that size, it uses a much smaller 10-32. Just something to be aware of.

I disagree with your analysis about the barrel simply because that is not what I’ve experienced with my gun.
I attempted to explain to you in an earlier thread that if the barrel isn’t snugged up with a wrench before the shroud goes on and isn’t installed using the correct process it will not be secure and like you said it would have to rely on the shroud and band..
So either it’s like I said and you didn’t “understand it just fine” or your rifle is defective and should be replaced..

Mine has zero play where it threads into the breach once tightened completely..
I can and have shot mine without the shroud or barrel band and the barrel by itself is rock solid.

I just like to give credit where credit is due & with this rifle I think the company went the extra mile to thread the barrel in the receiver and they executed it well imo.

I will say that I’m struggling to get the accuracy out of the gun that I expected, but I’m not certain at this point if it’s the barrel or some other part of the equation like the scope I put on it.
 
The gun and your barrel is designed so that you can not screw the barrel in tight. It has ports and a set screw dimple on both sides because you have to screw it in to the point that it will acceptably retain your magazine and either back off, or turn in more to get to the dimple for the set screw that fits best. If you are not in the right one you either won't be able to put in your magazine, or it won't be held in tightly at all. If you got lucky and it just ended up being snug, than good for you, but I had to choose. There is no way I can run this gun reliably without the barrel band, it's too long of a moment arm for the shroud system to deal with without it. That being said, with the barrel band in place, it is indeed strong enough.
 
The gun and your barrel is designed so that you can not screw the barrel in tight. It has ports and a set screw dimple on both sides because you have to screw it in to the point that it will acceptably retain your magazine and either back off, or turn in more to get to the dimple for the set screw that fits best. If you are not in the right one you either won't be able to put in your magazine, or it won't be held in tightly at all. If you got lucky and it just ended up being snug, than good for you, but I had to choose. There is no way I can run this gun reliably without the barrel band, it's too long of a moment arm for the shroud system to deal with without it. That being said, with the barrel band in place, it is indeed strong enough.

I understand how you see it that way but it is not.. because the barrel and the thimble
“ if you will” are two separate pieces..
The set screw goes in the dimple as you say and retains the “ thimble with the transfer port “ in it precise location then the barrel which is a completely separate piece threads into the receiver and also the thimble… so when you “snug” it up you will not be moving the thimble and mis-aligning the ports or affecting mag fitment.
Of course that’s only if you don’t overtighten it.

Call it luck if you want, somehow I must’ve gotten lucky all 3 times I’ve removed and reinstalled the barrel so far.
 
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I understand how you see it that way but it is not.. because the barrel and the thimble
“ if you will” are two separate pieces..
The set screw goes in the dimple as you say and retains the “ thimble with the transfer port “ in it precise location then the barrel which is a completely separate piece threads into the receiver and also the thimble… so when you “snug” it up you will not be moving the thimble and mis-aligning the ports or affecting mag fitment.
Of course that’s only if you don’t overtighten it.

Call it luck if you want, somehow I must’ve gotten lucky all 3 times I’ve removed and reinstalled the barrel so far.
Thankyou! Now I am learning something that I never would have guessed. My assembly feels like one part to me. I don't know what's holding it together but it seems solid. Now I completely get what you are saying. Maybe, some prototypes are solid, others are not. The picture on their website shows it as one piece too, so I didn't think it could come apart. I wish Macavity would chime in on this thread. I am not going to check if I can get it apart until after I accuracy check it this weekend. If it shoots great, then I'm certainly not going to touch it! Thanks for the info.
 
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I'm new to airguns. I lucked out and managed to purchase one of the Genesis .25 long barrel. I do not have any experience dismantling a gun like this and really since I've enjoyed shooting this one with decent groups at 40 yards in my backyard, I am not ready to experiment with it just yet. I do have a simple problem that involves the magazines. I am having a pretty consistent issue with 1 or 2 pellets in a magazine going into the breech at an angle causing them to not load. Since I really don't have any friends into air rifles to turn to, I am wondering if anyone might be able to give some advice. Asked Macavity a week ago and no response yet. I do love seeing the pictures and reading what you are doing to the rifle and in the future might try some of the adjustments.
 
I wrote above in post #28 about trying to turn down the spring tension a small amount and they just didn't design in extra hole positions for adjusting spring tension. These guns are the prototypes so maybe it will have adjustment features later on. If not, once CARM starts making mags for this gun, get those, I will be.

I mounted a 1-moa red dot on my gun tonight to just start trying it before my scope shows up and man, I do love this thing! My observations in this post are meant as constructive criticism not blatant criticism. That was why they put out a prototype, to get feedback. Not to get a pat on the back for trying. The problem with most reviews are they don't take the gun apart so they have no clue about what's going on inside. Some reviewers state that they test them just like they arrive and how you will get them, yeah OK, so what? How does that help me make a decision? That just means that I will be in the same boat as you when I get my gun, clueless. The truth is that I want a review that shows me what I am going to be dealing with down the road and how the gun is actually built. (Sub12airgunners.com does excellent teardown reviews, unfortunately he didn't do one for this gun yet.) The breech o-ring should be on the probe, the magazine should have extra holes to adjust tension, the screw to hold in the grip isn't the standard one, the buffer tube is mil-spec 1.148," I don't know if my thimble is supposed to be solid to the barrel or not, as Rvaughn's is separate, these are all things that I found out myself that weren't in the reviews that I saw. This is the kind of stuff that I want to know about and what I want Macavity to know about. Some are just fact points, some are questions, my only real complaint that I wish they would change is the breech o-ring placement to the probe. I think the gun is actually quite awesome and am very happy with my purchase. I put on a vertical grip and an MFT buttstock and it is excellent for offhand shooting. I sighted it in standing against a garage at 13y and put the data in Strelok, inputted the distance to my spinners, 83y, got my dope, and first shot, standing freehand, hit, nice. It holds very steady, it is light but has its weight in the right place and very solid feeling. I am happy with not having the extra parts of an extra guage I don't need, or on the fly adjustability that I don't want, so this prototype suits me better than what they will be releasing. They really did do a good job with it.
 
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First groups from 53 yards shooting JSB 18.13gr @892fps using a Bushnell Red dot. The dot covered most of these targets, and my eyes are going down hill, so I thought that this was actually very good. The black is three inches across. The actual group size was way smaller than the dot, and I didn't know what I shot until after because of the no magnification sight. All shots were fired with the factory moderator on, and I was moving zero between the bottom groups. I can work with this, can't wait for what this will do with a scope.
 
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View attachment 463641View attachment 463642

First groups from 53 yards shooting JSB 18.13gr @892fps using a Bushnell Red dot. The dot covered most of these targets, and my eyes are going down hill, so I thought that this was actually very good. The black is three inches across. The actual group size was way smaller than the dot, and I didn't know what I shot until after because of the no magnification sight. All shots were fired with the factory moderator on, and I was moving zero between the bottom groups. I can work with this, can't wait for what this will do with a scope.
That’ ain’t bad at all.
 
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