The Simrell FMJ (Full Metal Jacket) Review An amazing & inexpensive way to upgrade your DynaVap experience.


Hey guys, it’s Sneaky Pete here, and today I’m going to review on the new Simrell Full Metal Jacket (FMJ). This is one of the simplest and most effective performance enhancers that I’ve ever seen, it will totally change how your DynaVap works and what it can do, for only $10USD. It goes to show, that even the cap we know and love has room for improvement, and it’s remarkable how much this tiny little addition will make your DynaVap feel like a brand-new device.

The FMJ is made by The Simrell Collection, and I did a live interview with him where he goes over everything in detail. I will post a link to that right here so you can also hear it directly from the creator which I would really recommend. The FMJ is a thin sleeve that fits around your DynaVap cap, and it’s made from 99.9% pure copper. It has a slit directly opposite the logo, and a slight oval shape so that it better fits on your cap. The FMJ or Full Metal Jacket will work on any captive cap, so if you have a very old non-captive, it will not work on that. It’s also not made to work in an induction heater, this is designed specifically to work with a torch, and I would recommend using only a single flame torch to get the very best results.

The FMJ is easy to install, and just as easy to remove. To install it on any captive cap, hold the Digger Outer between your thumb and forefinger, orient the FMJ so that the logo is upside down, and then slide it over the top of the cap, with the logo ending up right above your thumb. An easy way to know if you have it oriented correctly is that when a cap is sitting flat on your table, the Simrell logo will be oriented in the proper direction. I like to rotate my FMJ a bit as you will find it is tighter over a certain part of your cap so find that sweet spot. If you want to take it off, simply slide it back over the top of your cap, essentially reverse the process of when you put it on, and off it comes.

Copper is not a new concept in vaporizers, the Vapman has been using a gold-plated copper oven since its inception and it has been out for over 20 years, and then the Anvil came out last year and showed everyone what copper can add to the equation when utilized in a different way. Copper has remarkable thermal properties, there are very few materials that do a better job transferring and distributing heat than copper, and most of those materials are extremely expensive. However, copper does a very similar job, and it is infinitely more affordable.

For reference’s sake, a DynaVap captive weighs about 0.78g, and the new Simrell Full Metal Jacket weighs about 3.26 g. So, what is the impact of changing your 0.78g stainless steel cap, into a 4g stainless steel and copper cap? When I describe it, you will understand how this is going to have a huge impact, and that most of those changes are positive.


Advantages & Drawbacks || How Does The FMJ Impact Usage?


The first change, and this can’t be understated, is that you no longer are required to spin your DynaVap when you heat it with a torch. This is probably the biggest sticking point when it comes to new users struggling with their DynaVaps and adding this $10 accessory will eliminate the need to spin. As copper is so good at conducting heat, it will efficiently distribute the heat all throughout the cap, rather than you needing to spin it so that your torch doesn’t create a hotspot. This makes your DynaVap so much easier to use as the spinning technique we have all acquired to get a good hit is no longer required in anyway. For me this is worth the price of admission alone, but there are numerous other advantages with the FMJ.

Not only is the 3g of copper going to distribute the heat, it is also going to add a dramatic amount of heat retention to your DynaVap cap. Keep in mind you can use this in one of two ways, to add more power, or to not add more power, and the heat retention will benefit you regardless of which option that you are aiming for, and we’ll go over how to perform both methods shortly.

If you are looking to increase your power, the additional thermal mass is going to add completely new heating capabilities to your DynaVap experience. This increases the mass by around four times, giving you substantial additional heat capacity to get a bigger hit.

Material can only absorb so much heat, so as soon as you start inhaling through a DynaVap tip and cap, it is going to start pulling heat away from your DynaVap tip. Adding on an FMJ is like adding on a big warm overcoat over your cap, it’s going to retain that heat substantially better to keep the cap warmer over time.

If you don’t want to add more power, the additional thermal mass helps to act as a buffer, meaning you have a significantly increased amount of time to complete your DynaVap hit. 

Everyone is familiar with the mad scramble of putting down your lighter and situating your DynaVap in your water piece while it is still good and hot, but the increased thermal mass adds a heat insulating layer which gives you ample time to get everything in place and complete your hit.

If you are looking to get the most possible vapour possible from your tip, aiming for a single hit full extraction to get the darkest sort of ABV possible, I think the FMJ is the easiest way to accomplish that with a DynaVap. I use this in a tip with one of our Sneaky Pete half bowl converters, and you can get an insane amount of vapour from that tiny little half bowl when you utilize the FMJ. For all the people looking to maximize the value from their material, adding this $10 accessory is a no-brainer.

The last benefit of the FMJ is the click buffer that it adds on. In general, with a DynaVap you want to respect the click, as if you heat it much after it clicks, you are going to end up scorching your material. With the FMJ on your tip however, I have heated my cap five seconds after it clicks, with no scorching whatsoever, just maximum vaporized ABV.

This buffer not only is the key to adding more power, but it also again serves to make your DynaVap experience easier. If you struggle with the click, this gives you a little elasticity to the process, meaning you have a few extra seconds of reaction time to stop your heating.

As much as I love this $10 enhancement, it’s not without its drawbacks, and the first thing is that it makes your DynaVap retain heat way longer. One thing people complain about with the anvil is how long it stays hot for, and this additional copper is going to stay hotter way longer then with a regular DynaVap setup. With the way that it fits on your cap, you more twist and lift your cap to get it off rather than just straight pull it off, and you simply can’t do that while the copper is hot, so you’re left waiting for it to cool down or using some sort of tool to remove it. If you like to do back-to-back bowls, I recommend going between two different caps, or using something like our metal DynaVap rest which will help to drink up the heat much faster than it just sitting out in the open.

After a lot of use, the copper seems to need an adjustment. As it is quite a malleable material, you can simply squeeze it when it’s on your cap to get a nice tight fit, but you do want to check this periodically to ensure it stays where you want it.

Finally, the FMJ loses that beautiful shiny finish very quickly. Anytime you are blasting something with strong heat from a butane torch, it is going to modify that material. After using the FMJ for a dozen or so hits, the metal is dull and no longer shiny. It doesn’t have an impact on how it functions, it’s just not as pretty.


How To Use The FMJ || Get The Best Results The Easy Way


Once you have it on your cap, using the FMJ is incredibly simple. Place your cap on a tip like normal, then you are going to take your single flame torch, and you are going to treat the S logo as a target for your flame. The flame of your torch should be about the same length as the FMJ, so adjust your torch height accordingly, and then apply your flame to the logo.

As we are not spinning it and rather keeping the flame in place, after a few seconds of heating you are going to notice a change in colour on the section where your flame is pointed at. If you move your torch closer to the FMJ, the spot becomes larger, and if you move your torch further away, the spot becomes smaller.

What you are trying to do is to aim your torch, so it is pointed directly at the logo, and then also adjust the distance so that the size of the colour change is the exact size of the logo.

This was a clever way to teach people how to use it properly, because when you point your torch to do that perfect logo change, you’ll get the optimal results. The results are quite similar between hits, but the primary factor is going to be how quickly you optimize your flame position, and it may be a little tough at first. If you don’t really utilize the logo and the colour change to aim it properly, you will more guess by the click, and that can work just fine as well, though I would keep the torch pointed at the lower segment rather than the upper tip section.

If you want to use the FMJ simply to remove the need to spin and not to affect its performance, I will stop my torch as soon as you hear the click, just like normal. This will make it hit in a much more similar (though not identical) manner as to using it without the added copper. If you want to use the FMJ as a single hit extraction supercharger, find that optimal flame position as soon as you can, hold it as good as you can, and go multiple seconds after the click.

When you are calibrating it with your torch, first I would stop at the click so you can assess that but feel comfortable going even three seconds after the click with most torches. I have pushed mine to five to get a maximum dark sort of extraction, but I wouldn’t go any further than that.

Overall, the Simrell Full Metal Jacket is an excellent DynaVap accessory that comes in at a remarkably low price. If you are a DynaVap aficionado, you owe it to yourself to at least try one of these. The price of admission is so low that I really don’t think it has to enhance the experience all that much to be worthwhile, but in this case, it enhances it a tremendous amount, making the value insane.

It will take some adjustment with your normal process, it stays hot way longer and I don’t really think it enhances the cap on tip experience, however all the beneficial attributes far outweigh any negative aspects of the accessory, and kudos to Austyn for releasing such a low-priced accessory that adds so much to the experience.

Find the Simrell FMJ at or and as always,