Posted: 11/18/2021 5:39:41 PM EST
Home from work sick today so I'm going to take a stab at this. Hopefully the cold medicine doesn't effect the the content too much. This is by default going to essentially be a review of what I run since I don't see a practical way to include all the different options out there. Mine is a pretty basic setup so it should act as a decent baseline. It would be nice to have a compatibility chart at some point but that's beyond the scope of this thread and probably outside of my organizational abilities.
We'll start with shrouds. This is the bracket that allows your helmet mount to be attached to your helmet. Mine are Wilcox and I'm assuming will accept any Wilcox mount and work with the Norotos Rhino2s that I run. Not sure if the other Norotos mounts work. I have 4 Wilcox shrouds and 3 Rhino2s and they all snap in easily and have very little play once connected.
This an example of a Willcox 3 hole.
This is a Wilcox insert shroud in a bump helmet
The notch in the top hooks into the shroud and the spring loaded button holds it in
Once installed pushing the button releases it.
This will also serve as the 1st lesson in having your devices tied off. You'll notice as we go along that there's lots of buttons that can dump your expensive gear on the ground. The buttons are out of the way but if you use your stuff a lot it's inevitable that one will get pushed or you'll fail to snap something all the way in and it's a lot better to have your device swinging on a lanyard vrs hitting the ground.
Moving on to the basic functions this is the mount deployed and flipped up when you want your devices out of the way.
This knob is a friction lock which allows the mount to slide on the rails above in the vertical axis. This allows you to set the height of your device in relation to your eye.
Looking at the bottom of the mount this knob is a friction lock which allows the socket to slide forward and back on rails to bring your devices closer or further away from your eyes on a horizontal axis.
This last knob controls the angle at which you're looking through your device. Think of it like looking through a scope and getting scope shadow and adjusting your head position to get that nice clean circle through the eyepiece.
Side to side adjustments or ipd is controlled on your device or by the arm that connects your device to the above mount and I'll cover that in later posts.
This couldn't have been posted at a better time. I needed this lesson in writing as I am putting my helmet together this week and have no clue what I am doing.
Next we'll do the sockets on the end of the helmet mount. This is where paths will split and I went down the individual device path. I will be getting into j-arms and bridges which won't apply if you have chosen a device that covers both eyes like a pvs7, pvs15, pvs31 etc. You will simply need to figure out what kind of socket your device has and you will be done.
This picture shows a stock Norotos Rhino2 on the right with the plastic j-arm that most people will receive with their pvs14. On the left is a Rhino2 that has been converted to a pvs15 dovetail socket along with a Mod Armory dovetail j-arm.
Next is looking at the bottom of the mounts as well as the relevant sockets seperate from the mount. I've indicated the roll pin that needs to be removed to get the socket off. There is a similar one at the front. If you're careful you can reuse the pin and if not one of the roll pins from an ar15 lpk cut in half will work. The second post of this thread has info as well as a video on how to perform the conversion.
Excellent write up
There are a few reasons for converting to the dovetail 1st among them being that more devices and mounts are available with the dovetail. The dovetail also in my experience has a better lock up and a satisfying click when properly engaged. To be fair my only experience with the stock setup (usually called a bayonet)is the shitty plastic arm (SPA for future reference) so I'm sure the machined metal versions are better.
Another factor is the bayonet version of a given mount will be taller which can cause you to run out of up travel on your helmet mount before your device is level with your eyes. A couple members here have reported this being an issue with the bayonet version of the Mod Armory d14 bridge and it could be an issue with other mounts as well. These pictures from Mod Armory's site illustrate what I'm talking about.
Long story short I'd only recommend the bayonet interface for use with the SPA and when you buy your dedicated mounts to get the dovetail version and a conversion socket or if your not going to run a Rhino2 to get your chosen helmet mount in a dovetail from the start. We ran the bayonet and SPA for awhile while we waited for our dovetail bridges and arms and it's functional but not ideal. It will however get you up and running if you're waiting for out of stock items which is often the case these days. Tnvc usually has the pvs15 socket in stock for around 75$ so you can have one on hand when your dovetail stuff shows up.
Next I'll do a public service announcement for anyone running the SPA and bayonet mount and this will hopefully reinforce why you always want to have your devices tied off. Both of the SPA we received had an out of spec bayonet and many others have reported the same thing. It would seat and even make a click but the latch would not full engage. It was necessary to file it down like this to get it to latch.
Apparently I didn't file enough because even though it is capable of latching I sometimes would have to hook my finger under the latch and pull up to get it to fully engage. I learned this the hard way on one of my 1st trips out when I thought it was engaged but after walking around a bit it popped out and swung down on it's lanyard and whacked me in the face Did I mention to always have your devices tied off?
Moving along to ways to connect your devices to your helmet mount we'll do options for a single device 1st since that's where most people start.
1st up is the classic j-arm. I'll use the SPA and Mod Armory that I showed previously. These operate in a similar fashion and there are other companies that make their own version. In both cases the screw that sticks through the end of the arm opposite the dovetail/bayonet threads into the mounting boss on the pvs14.
Finger tight is good enough and I haven't had one come loose. You don't want to strip the threads and besides your device is tied off right?
The dovetail/bayonet snaps into your helmet mount and the arm will swing back and fourth on the center pivot to line up in front of either eye. This is also how you adjust side to side. Between the arc of the swinging arm and the vertical adjustment on your helmet mount you can get it fine tuned exactly where you want it.
Next I'll cover a couple less conventional ways of mounting a single device. These add an additional element in that they can be rolled upward out of your line of sight without flipping your whole mount up.
On the left is a Mod Armory d14 bridge with the socket and screw removed from one side. This weighs about 1oz more than the j-arm. My wife has vision issues in her left eye so this is her preferred mount since she can wear her pvs14 over her right eye and roll it up with one hand while placing a thermal up to her eye with the other. She's gotten quite fast at this with practice and does it all in one motion.
On the right is the new noisefighters j-arm that has an additional joint in addition to the main pivot. This allows it to be rolled up similarly to the d14. I've been using this recently and it has the additional benefit that the double joints allow me to max out the vertical on my helmet mount while still keeping my pvs14 centered over my left eye. This leaves enough open space over my right eye that it's relatively easy to shoulder a rifle with a thermal without moving my pvs14. It's not great but better than anything else I've tried.
The noisefighters j-arm and the d14 mini arm attach the same as the other arms.
The mini arm snaps into the bridge...
Mounted over the right eye.
Very nice tutorial. Solid info on options out there.
On the USGI J-arm. The pivot lever is the weak point of the issue system, IMHO. So once you have bayo fully inserted(!), then you can run a single bungee, from one rail, to under the pivot lever, to the other rail. I used to put an extra pull tab on the bungee, which would nestle in right under the lever, so that if anything bumps the lever, it's mechanically locked in place and can't release (well I guess if you really tried, you could get it to, but whatever).
On the USGI Rhino II mount. I think this is a very good entry-level mount. With the -15 dovetail adapter, it's actually a pretty solid deal.
On shrouds. I would advise staying away from 1-hole jobs and going with an OpsCore or Wilcox 3-hole unit.
So, a basic set up might look like this: OpsCore shroud, Rhino II mount, USGI J-arm. This set up served me well for many years.
Then, an upgrade might be: Wilcox shroud, Rhino II w/ dovetail, (aftermarket) J-arm w/dovetail. This removes the weakest point of the GI set up, again IMHO.
And finally you might like: Wilcox shroud, Wilcox G24 mount, Wilcox J-arm. This could arguably be called the industry std.
Thanks. I was going to get into bridges also but my snot fountain is subsiding and I've got a lot to get done before Monday so it will have to wait. On reflection I'm thinking this thread is best left as a mount and jarm tutorial so if anyone can do reviews of alternative choices especially mounts and hopefully a Norotos dda that would be appreciated.
Solid job brother especially 1/2 tits up here. Yeah all we need is someone to chime in with Norotos goodness to illustrate that option.
This is solid info that you see questions on every week.
Then someone could maybe chime in with compatibility. I know I've read those threads but just can't remember all the details.
Very cool to have a broken out sub-forum for this stuff and thanks for the thread. I had a lot of these same questions when I got started about a year ago and had to hop all over the internet to figure out why my SPA sucked and gather the info to do the ModArmory dovetail / PVS15 mod. I'll be following along because I'm sure most of you have forgotten more than what I think I've learned so far.
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