Last night I tore what I think is the detent spring and had to cut about four to five coils of it. I did not fire the weapon, just did a function check on it. The function check went fine. No problems. I am referring to the spring that does on the back side of the end plate. The one that is held in place by the end plate and castle nut. My question is will the four to five coils make a this weapon on safe to shoot? Must i replace it, or can it wait? Further more I really could not figure out the purpose of this spring either if some could explain that it would greatly appreciated?
That spring provides pressure on the detent for the take-down pin. As long as there is sufficent pressure to keep it in place you should be fine. Make sure that its not “too” easy to push the take-down pin out. If it is I’d get a new spring.
I would replace it. It is conceivable that the difference in length will result in less tension on the detent pin and it may not be secure. IMO it’s not worth it.
yeah, that is what I figured. I just hate that shipping will probably cost more than the spring. I know no one local will have one.
Lesson learned I will have to order two to three of them.
I know what you mean. Might be worth your while to just get a LPK minus the FCG. That way you have spares for the other small parts too. IIRC, grant has those for a little over $60.
There is an outfit in AZ called Citizen’s Armory.
They sell small parts and ship them in a stamped envelope.
I can’t tell you who’s parts they sell.
I know they sell some Spikes stuff and Glock parts.
PM sent
Send me an email and I will send you couple of them 
We bought 1000 of these selector/rear take down pin detent springs, we mostly give them to repeat customers as SWAG 
I seem to recall hearing that you can ratfuck an AR detent spring out of a bic lighter.
Might be worth $1 and a trip to the local convenience store to find out…
I heard that too, I’m not sure if the springs are the same though. The detent spring’s cross section is flat, not round.
I’m sure in a pinch it’d work, but I’d get it swapped out with a proper one as soon as I get a chance if I ever used a BIC lighter spring lol :sarcastic:
Can’t beat Duffy’s offer. Having spare parts around is a good idea too.
Is this a combo pack?
The selector spring is the same as the ejector spring. The pivot and takedown pin detent springs are the same.
My mistake, it’s just the selector detent spring:jester:
From L to R
Selector/ ejector
Takedown / pivot pin
Bic lighter
Diameter looks right, gage is thinner, coil count and length are short. No reason it wouldn’t work in a pinch. Not really a part exposed to a lot of stress and repetition or in need of exact rebound.
A lighter’s spring may be expected to perform 1000 times before the whole thing is discarded, whereas the detent spring usually lasts decades and tens of thousands of operations before replacement. In a pinch it’ll work, provided you have a BIC lighter that can be cannibalized for its spring, but if I were in the situation, I’d replace it with a proper spring asap
Why not do the captured detent spring mod on your lower? You have to cut about 4-5 coils off the spring to do it anyways.
Forgive my ignorance, but what in the hell is the captured detent spring mod?
Beat me to it.