AR Trigger & Firing Pin

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I will let you know when ive grown a pare.

[AR15]

If you use both Hammer and Trigger springs (Yellow JP) then you will most probably get light strikes. Swap the original Hammer spring back in so that the hammer goes off with full force. You can run the lighter yellow trigger spring fine with this setup. Add some molly grease to the primary sear too (the one at the front). You should get your pull weight down to about 5.6 or 6.3 from 7.3 if you do this. It will depend on the trigger make though.

You could also try bending the legs of the yellow Hammer spring down to create more force too. Check that the hammer spring is installed correctly.

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Tried all the yellow springs in the trigger and it was a nightmare, tried firing 5 shots and not a single shot, so put my original hammer spring in and left the others and its working fine, just a bit gutted it wouldn't work with the yellow hammer spring in, it was nice & smooth and a lot lighter with that in, but at the end of the day, its no good if it doesn't shoot.

[DanTheMan]

The CMC drop in triggers work well with .22LR, just put one in my V22 last week and am very impressed with it, they are only $168 so work out very cheap if you get someone to pick one up in the US for you.

[Mattnall]

JP light springs (yellow ones IIRC) aren't really for 22LR.

Where does it say that?

My post above.

But looking at the responses here, my previous experience (and even the comments in your own post to putting the original hammer spring back in), would seem to justify the statement.

[John MH]

JP light springs (yellow ones IIRC) aren't really for 22LR.

Where does it say that?

My post above.

But looking at the responses here, my previous experience (and even the comments in your own post) to putting the original hammer spring back in, would seem to justify the statement.

But remember not all ARs are the same, some work ok some don't. JP do not comment on suitability in .22LR ARS, everybody is entitled to their opinion though. A JP Spring Kit is a cheap option that if it works then great, if not then the next step up to a replacement trigger and hammer is considerably more expensive.

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Im getting a bit confused now, I put those springs in and it gave me a very nice trigger, but it worked when it felt like working, if I put a new trigger in with softer springs like the jp yellow, isn't the same thing going to happen, it working when it feels like working ?

[John MH]

A new trigger is a whole different proposition. The aftermarket triggers are generally better made and the engagement surfaces honed to make them smooth and crisp so that even with a heavier spring they feel lighter. They vary in price as well from anything around £100 to £300+, in some respects you get what you pay for.

[AR15]

The problem is that a standard single stage AR trigger has a primary sear setup that is manufactured in such a way that it has to move the hammer back slightly before it can disconnect and let said hammer go forward. Its excessive positive engagement for safety.
You can see the geometry set up and what happens very easily by taking your upper away and looking carefully at the cocked hammer in the lower, if you look from the side and carefully pull the trigger (don't let the hammer fly forward and hit your lower btw) you will see the hammer dip down slightly before it is released.
That movement is the creep you feel before the break. Its the primary sear on the end of the trigger pushing the notch in the hammer out of the way before it lets go. The hammer is being forced forward by the hammer spring so the more powerful the spring, the more resistance you will feel, it has quite a lot of force to move before the hammer can release.
If the sear surfaces are not completely smooth then you will feel rough creep before the break too.

Custom single stage triggers have the sear geometry set up in a more neutral or less aggressive positive engagement so that there is more of a slide before the break and the hammer does not have to be forced to rotate that much or at all before the sear disconnects.
The surfaces are polished by hand or wire edm cut for a smoother feel too.
They may also have reduced length sears so that the length of creep/slide is much reduced and the trigger break feels crisp.

So with the JP Hammer spring installed there is much less resistance against the primary sear and thus the creep and break feels better, but there is also not enough power to accelerate the hammer to make the rimfire ammunition go bang reliably.

If you fancy you can play about with a standard trigger spring to see if you can lighten it (the JP Hammer Spring will never work reliably, if at all in a rimfire with a standard Hammer), I would suggest buying a few for your experiment.
Cut one leg off a standard Hammer spring and try that (make sure you keep the one that engages with the notch on the trigger pin or your pin will walk out).
Or get a JP red spring.
Or get the JP low mass Hammer (it may work), avoid if it has a notched face.

If it was me I would cut the hook of the back of your existing standard hammer to reduce the mass (bobbing its called), that may then speed it up enough to use the Yellow JP Hammer spring. A bobbed hammer is also slightly easier for the bolt to cock on its way back and can help short stroke problems in rimfire and centerfire rifles.
Google ''bobbed ar15 hammer'' to see how to cut it. If you mess up then just IM me and I can send you a new standard one.

If you feel brave then you can change the sear angles and make a crappy standard trigger into a very nice single stage, but it takes a bit of work.
Worth buying the parts and having a go though as you would learn a lot :)

Hope that helps you.

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Cheers mate you have explained it great, even I could follow your instructions, it doesn't seem to daunting the way you've explained it, and I will have a go at it next week when im of and let you know how I get on, thanks again mate.