Length: 25mm (~1″)
Diameter: 94mm (~3.7″)
Battery type: 18350 to 18650 (telescopic, max battery length 76mm)
Battery Connection: 510
APV Type: Mechanical
What’s in the box:
- (1) All brass telescoping V3 MOD
- Self adjusting positive pin (spring loaded).
- All brass construction; low voltage drop.
- Accommodates multiple battery sizes.
- Clean cut and well formed threads.
- Reverse threaded locking ring.
- All brass construction; tarnishes easily
- Chinese clone.
- Spotty availability.
- Threads loosen rather easily.
- Locking ring threads can become “locked” when engaged and the switch is loose.
- Switch loosens with regular use (see errata section below for fix).
The Bottom firing switch on this mod comes unscrewed with normal use. This can lead to unintended firing (in theory), but mostly leads to the locking ring not engaging or disengaging properly. Once stuck, the easy solution is to spin the firing button counter clockwise a bit to allow the locking ring to spin all the way around on the internal threads and re-engage.
This is due to the way the firing button and the negative pin are connected. The simple fix is to disassemble the switch, and wrap the threads on the firing button post with Teflon tape (the thin white stuff sold at hardware stores, it’s super cheap). I’ve seen people use locktite, but that will preclude ever taking the switch apart without damaging it, and if the switch gets dirty or gritty feeling, there is no way to fix that without disassembly.
The entire mod can be disassembled without any tools, which makes cleaning convenient. The picture above shows it mostly disassembled, the top cap also screws off, and can be fully disassembled (as can the switch).
You cannot see it from any of the pictures online, but the ribbing on the body of the mod is actually square cut. This makes the mod quite grippy, and I like it. I only note this because I was under the impression that the ribbing on these was rounded, and didn’t realize it was actually square cut until I handled one at a local B&M.
You have a choice to make with an all brass mod; do I polish it or not?
Brass tarnishes fast, especially when you handle it. The ribs that make this mod so nicely “grippy” are also going to add enormous pain to any polishing effort. Personally I like the look of tarnished brass. If you’re going to polish it, you can use any suitable brass polish (such as Brasso or Mothers Billet Metal Polish).
Actual cleaning can be done with a cotton swab and some high alcohol content isopropyl alcohol.
If you are concerned about conductivity, you can take a brass wire brush to the threads once a month or so if desired. I usually use an old (clean) toothbrush to clean out the threads, wipe the 510 connection with a cotton swab dipped in isopropyl alcohol, and then wipe the whole thing down with a clean microfiber cloth.
Brass has very good conductivity, but if you are really worried about getting the absolute best connection possible, you can apply a tiny bit of NO-OX-ID A-Special (Noalox doesn’t work great on brass) to the threads (not the 510 threads, just the other threads on the mod), but I don’t think it’s necessary at all.
I picked this up at a local B&M on a visit to replace a misplaced beater K101 (which I’m fairly certain is somewhere chillin in the Sierra Nevada Mountains where I frequently go shooting). I paid about double what you could order this from Fasttech for (which is ok because it is supporting a local vendor, and I feel it is worth every dime). I’ve been very happy with the performance of this mod, and would definitely recommend it to anyone looking for an inexpensive mech.
I feel conflicted about buying a clone, but not terribly so as I would never spend Sentinel money on a beater mod.