New Trigger Spring = New Trigger Pull?

[ghettoblaster]

I know the above is like a big "duh" statement, but being new to the AR building hobby I figured I'd verify before I screwed something up or made something worse.

I just completed a build using an NFA multi caliber lower receiver and a S&W upper chambered in 5.45x39. However, the NFA lower, not unlike the Plum Crazies, has a plastic fire control group which, although not bad, feels cheap and I don't like the trigger pull. The plan from the beginning was to replace it with a steel trigger, either an ALG or a New Jard. The ALG is the nicer of the two but the trigger pull comes in at 6+lbs. The New Jard seems like a nice one too but the trigger pull is around 4.5-5 lbs. Either way, I want one around 3-5. Sure, I could do a drop in FCG with adjustables for around $150-$250 but the 5.45 upper has a designated hammer spring that I don't want to mess with (I figure they wanted me to use that one for a reason...). This leaves me with just the standards FCGs that I have to put in one piece at a time.

I believe someone mentioned on here previously that you can adjust the trigger pull by ordering a new trigger spring from some place like Brownells.com. If that's the case then it doesn't really matter which FCG I get, whether it be DPMS, CMMG, ALG, or that New Jard configuration, because I could just swap out the trigger spring.

Can someone confirm this?

btw yeah I know I should have included pictures. I'll get them out here soon if anyone cares to see them, but it's really nothing special yet.

[cofi]

Your best bet if your doing that would be to buy the spring then take the whole unit over to Bert at Hp tactical to polish....the spring will give you a lighter pull but the trigger will still be gritty and creep

[cofi]

Bp tactical.....stupid autocorrect

[Kaiser.Shooter]

If you go with Jard non-adjustable, you can get a different trigger pull springs from midwayusa, this is not the hammer spring this one located under the trigger.
Jard Trigger Spring Application Chart:
http://media.midwayusa.com/charts/Jard_Trigger_Spring_application_chart.htm

Jard Trigger Spring 1012- http://www.midwayusa.com/product/213565/jard-trigger-spring-1012

Jard Trigger Spring 1014- http://www.midwayusa.com/product/753879/jard-trigger-spring-1014

Jard Trigger Spring 1013- http://www.midwayusa.com/product/862343/jard-trigger-spring-1013

[BPTactical]

Try a JP reduced trigger spring and see how you like it. But also understand that you have the hammer spring working against you as well. There is the reduced power hammer spring as well but that may come at a cost of reduced reliability, especially if you get some hard primered ammo.

[68Charger]

Try a JP reduced trigger spring and see how you like it. But also understand that you have the hammer spring working against you as well. There is the reduced power hammer spring as well but that may come at a cost of reduced reliability, especially if you get some hard primered ammo.

since he mentioned 5.45x39 upper, he's dealing with hard primers- with the AK74, the Russians spec hard primers so they don't have to put in firing pin springs.

[Great-Kazoo]

since he mentioned 5.45x39 upper, he's dealing with hard primers- with the AK74, the Russians spec hard primers so they don't have to put in firing pin springs.


Why not run a stock (usgi) setup and see what works and what doesn't before you bring variables in to the picture.
FWIW: I have a JP set up in my rig went to a different commercial ammo and experienced light strikes. went back to the stock hammer, keeping the lighter trigger spring and no issues.
Shoot first, spend later.

[68Charger]

Why not run a stock (usgi) setup and see what works and what doesn't before you bring variables in to the picture.
FWIW: I have a JP set up in my rig went to a different commercial ammo and experienced light strikes. went back to the stock hammer, keeping the lighter trigger spring and no issues.
Shoot first, spend later.

I don't disagree, was just pointing out that he's dealing with harder primers than 5.56 normally has. A USGI spring may work, especially with polished pins and well lubed, but I would bet against any reduced power hammer spring working reliably on 5.45x39.

And while I don't think the OP is necessarily concerned about this, another factor to consider is lighter hammer springs lead to longer lock time.

[ghettoblaster]

I don't disagree, was just pointing out that he's dealing with harder primers than 5.56 normally has. A USGI spring may work, especially with polished pins and well lubed, but I would bet against any reduced power hammer spring working reliably on 5.45x39.

And while I don't think the OP is necessarily concerned about this, another factor to consider is lighter hammer springs lead to longer lock time.

Yeah I've got the right hammer spring for 5.45 - just mostly curious how to get the trigger pull down where I want it. Replacing the hammer is a must too since the stock one is composite polymer same as the rest of the lower. It may work just fine but if I'm replacing the trigger then I don't want it to be steel on plastic. Rather just replace the whole FCG.

What kinda treatment does that BP tactical do on triggers to make them so smooth and what does that generally cost?

[SideShow Bob]

What kinda treatment does that BP tactical do on triggers to make them so smooth and what does that generally cost?

After a trigger job from Bert, your finger will think it just had SEX......:)
Finger Bang City !!!!!!!

Save your self tinkering about, go to Bert first....

[ghettoblaster]

Finally order the ALG trigger from Brownells. $50 out the door with shipping and handling..... I'll see how it handles then decide whether to install a new trigger spring.

http://www.brownells.com/.aspx/pid=53928/avs|Manufacturer_1=ALG%20DEFENSE/Product/AR-15-M16-ALG-TRIGGERS (http://www.brownells.com/.aspx/pid=53928/avs%7CManufacturer_1=ALG%20DEFENSE/Product/AR-15-M16-ALG-TRIGGERS)