Disclaimer: I am not a gunsmith and do not recommend you modify the internals of your pistol without at least having some knowledge of the mechanics. If you have none, then take your gun to a gunsmith to perform this mod.
So i picked up a 709 earlier this spring. The thumb safety and 2nd strike capable were two of the biggest selling points for me. Coming from a Bodyguard 380, I was already accustom to those and happy to have them in the 709. Only gripe about this piece was the long trigger travel in SA mode. Just didn't care for it. So I took the plunge and pulled the SA sear/spring/pin out of the sear block. This mod was very easy to do. I started by drifting out the two rear pins holding the sear block in place.
You have to gently pry the block out with a small flat head screwdriver. Once it raises a touch, you can pull it out by your fingers. There was '1' pin towards the rear that holds the SA sear and spring in place. Its not a press fit or roll pin, it just literally slides out. Can use something small, screwdriver, toothpick to push the pin out. And when done, your left with the three pieces that make up the SA mode
Here is what the pieces look like put together. Sorry its upside down, but you get the idea.
When removed, there is a empty channel where the SA resided
Next steps was to replace the striker spring. After researching this mod on this website, I came across a post by BigAl512. Problem was his pictures were missing, back when Photobucket screwed everyone over, breaking their links. So I reached out and we chatted a little bit about this mod. He said for his conversion he used a Honor Guard HG9sc striker spring. He spoke to the owner of the company and got a few of them to test. So he passed the info along and I contacted Honor Defense. I spoke to the owner Gary Rammey and told him what I was trying to do. He openly admitted that when they were developing the HG pistol/s, they initially used Glock striker springs for the testing. They now manufacture their own, but said the dimensions were identical to a Glock stock 5lb striker spring.
I decided to try a Glock Xtra power 6lb striker spring from Wolf. Not sure why, but I also bought a Reduced power 4lb just in case I didn't like the results.
Following BigAl512's post [https://www.taurusarmed.net/forums/700-s/394057-709-hg9-striker-springs-trigger-set-screw.html]
, i figured if the HG spring is a match for Glock's stock weight of 5lbs, and if I'm using Xtra pwr 6lbs, maybe I should do 4 coils vs 3 he cut off the HG spring. Took it to the range and immediately noticed I had a problem. About 1 out of every 3 rds were light strikes. As you can see, the top row are the light strike rds. Next row went off without an issue, and bottom row were 2nd strikes.
Taking things apart, I lined up my oem spring vs the 6lb. I realized that I probably took off 1-to-many coils. So I decided to try the 4lb spring and to my surprise, even though the 4lb spring was considerably longer than the oem spring, it fit without any trimming. I had full trigger travel under DA. Confident the 4lb would still be too light for use, I know knew that I needed another 6lb spring. And DON'T cut any coils this time. So before I re-ordered from Wolf again, I asked myself, can I go heavier?
For S&G I searched for a heavier spring and came across the 'Glock Blue 31 Newton Extra Power spring' for $10 at RockYourGlock. The '31 Newton' equates to 7lbs of force. They also had a Red 28 Newton '6.29lb' spring, but for some reason it was $15. So I went with the 7lb. Here it is compared to the oem spring
Again, like the 4lb, this 7lb spring dropped right in the captured striker assembly without any fitting or trimming. I still retained full trigger travel without any stacking. So I took it to the range again, and shot 50rds. This time was 100% reliable. No more light strikes on the same ammo. For reference, I was using 115gr Blazer brass fmj for both tests. So by eliminating the SA mode, I have gotten rid of the trigger slack issue. And with the increased the pull weight, its results in solid ignition each shot. To me, this makes the gun near perfect for me. I hung up my 380 and now carry this daily.
I like to thank BigAl512 on here for providing me the information on how he achieved this mod on his 709. I'd also like to thank Gary Rammey at Honor Defense for sharing his knowledge. Its not every day you can talk to the president of a firearm company, tell them your interested in one of their parts to modify a competitor product, and they still give you that level of attention and detail. I thought that was very cool on their part.