I have used several TechT products but nothing similar to the hair pin trigger kit.
A-5 with an Apex barrel.
Spider Pilot with progressive barrel.
Reduces trigger pull. Decreases reset time slightly.
Can damage your hammer and sear if you use the wrong sear stop pin.
I played around a lot with the different pins following the instructions given on Tippmannparts.com. I had to play around for a while to get a combination of pins that worked well and also provided the trigger pull I wanted. After I was done I found a combo that worked well for my tastes and worked very efficiently.
Some of the problems I ran into while trying to get my gun to work were 1) the gun going full auto, 2) the sear not releasing the hammer, and 3) not being able to get my safety back into the trigger assembly.
1) If too large of a bottom sear pin is used the gun will go into an artificial full auto because the sear will not catch the hammer. The hammer, therefore, will not reset and will start another cycle. Putting a large bottom sear pin will also create extra stress on the sear and the hammer because it cannot go up far enough to catch on the hammer. I would recommend not going anything over a 3 from the set.
2) When I used the 4 from the hair pin trigger and the 1 for the trigger stop I had a problem with the hammer not releasing at all. The trigger could not make enough contact with the sear and so the hammer would not release every time I pulled the trigger. Like I said, this problem is fixed by using a slightly smaller bottom sear pin.
3) When the trigger stop pin is put in place (either 0 or 1 depending on preference) there was a slight problem with the little piece of the trigger that normally fits perfectly around the safety. Since the trigger does not go all the way forward compared to its normal place the small piece of plastic juts out just slightly. Unfortunately it sticks out just enough not to be able to get the safety back into its proper place. This can be easily solved by taking a file to the small piece of plastic and making it shorter. Doing this will not affect the function of the trigger and is solved in less than 10 seconds using a coarse file or sandpaper.
After finding the proper pins to use and my preference for trigger pull I was very pleased with the hair pin trigger. for those interested I use the 1 for the trigger stop and a 3 for the bottom sear pin.
The hair pin trigger does exactly what it says it will. Since every gun is slightly different some people may be able to get away with using different pins and get different results with each. This upgrade does require a bit of work but I was able to test many different configurations of pins with many different results giving a broad range able to suit many individual preferences.
I do not regret buying this upgrade at all. It was worth the $20 I spent for it. I have to lower the rating only slightly to a 9 because it requires some tinkering to get it to work properly.
Boo Yaah eLCD Frame
14" Smart Parts Progressive Barrel
Fasta 18v LCD
Very limited instructions
Takes some tweaking and possibly some modification to your trigger assembly
I purchased the TechT Hairpin trigger kit for about $20 from TechT's eBay store.
This product actually works by shortening the travel of the trigger and/or sear. This leads to faster rates of fire and faster hammer resets.
After a little bit of tweaking and some modification to the safety "knob" this thing works great!
I had to slightly file down the safety "knob" in order to allow smooth movement of the trigger. This was required since the pins I selected caused the trigger to rest slightly higher - interfering with the safety. Safety is still fully functional and works great.
I have the double trigger on the semi-auto frame. The double trigger allows for even faster rates of fire when coupled with this Hairpin kit from TechT.
I'll describe the stock trigger and then the modified trigger (with the hairpin kit and double trigger kit)
Long, 'mushy', extra unwanted 'overpul' (after the marker fires the trigger can still move backwards), slightly wobbly.
Double Trigger with TechT Hairpin Kit:
Very Short, snappy, solid, precise, no extra 'overpull', little side-to-side play.
I would recommend this product to anyone who wants an affordable trigger upgrade (around $40 for trigger and hairpin kit) who doesn't want to spend $100+ on the e-grip or who doesn't like the 'throwing action' of the response trigger. Definately a worthwhile investment.
Tippmann 98 Custom Basic
Flatline Barrel w/ Tactical Rails
GTA Expansion Chamber
TechT Hair Pin Trigger Kit
Cyclone Feed System (Votex Mod, Lightning Rod, Squishy Paddles, QEPH)
Low Profile Hopper
Red Hot Power Tube w/ Derlin Bolt
TechT Zero Kick Hammer
Adjustable M16 Sight Rail
Tippmann Bravo One
Cyclone Feed System
Aluminum Power Tube w/ Derlin Bolt
Remote Line Adapter
TechT Low Pressure Spring Kit
Reduces Trigger Pull
Works Well with RS
Can cause damage
I didn't like the look of the upgrade at first, it comes with 5 different pin sizes and you are basically instructed that pins 0 and 1 are for the trigger and 2-4 are for the sear. Other then that you are given very little direction on where to go. Basically, you are to find a combination best suited for your marker to decrease your trigger pull and not have any resulting problems.
It is without a doubt that this mod definitely increased my RoF. Again, with the RS and Double Trigger, you have the perfect full auto pneumatic solution. I was easily getting 15-18 bps with these mentioned upgrades plus the cyclone feed system. If I understand this upgrade correctly, the trigger pull is not necessarily reduced, but more so the reset when you let go of the trigger is reduced. You pretty much don't have to full let the trigger go to reset it. Just thought I'd throw that out there. And again, with the Response Trigger, this is an awesome upgrade. Because the Response Trigger more or less forces the trigger back to the ready position, it now has about only 1/4 of the work to do to reset the trigger and therefore makes your RoF much higher.
The installation process was a bit of a pain. You need to mix and match pin sizes to get the perfect combination for your marker. Its all different depending on your internal upgrades. I have the Zero Kick Hammer, Double Trigger and Response Trigger to account for and I found pins 1 and 3 worked the best. These are clearly marked by how many grooves they have. I tried using 0 and 2 in my Bravo One with E-Grip and the sear wouldn't catch the hammer so it was basically full auto with no way to stop it. You really need to keep an eye on your sear when you are using this upgrade and firing a high RoF. Check it periodically for damage. So far mine is doing good but I know they can cause some havoc.
If you have the Response Trigger I strongly suggest looking into this mod. Otherwise you won't get much of an advantage from it. It will help you, but it works best with the RS I find.
I give the hair pin trigger kit an 8. It does what it says it will do, but its up to you to find out the best way for it to do that. It doesn't take a lot of testing. Really there are only 6 combinations of pins, its just a pain. Plus it has the potential to cause some damage if you are not careful.