14 replies to this topic

[JeffCSR]

In an AR15 with lightened springs, namely JP 3.5 or 4.5 , how much weight would you take off the hammer to keep reliable ignition? I ask here becuz this seems like the right forum to ask it in, my apologies if it's the wrong spot.

[dshooter3]

Use the JP low mass hammer and you will be fine

[StealthyBlagga]

The photo below shows how much I removed from my standard AR15 hammer. This rifle has a JP trigger with yellow springs. I don't recall EVER having a light strike or other ignition problem. HTH.

[JeffCSR]

Use the JP low mass hammer and you will be fine

Thanks, I'll consider them when I replace the O.E. ignition parts which suck, very creepy and very heavy/inconsistant trigger pull. Wanted to try lighter springs (keep it cheap) for the moment.

The photo below shows how much I removed from my standard AR15 hammer. This rifle has a JP trigger with yellow springs. I don't recall EVER having a light strike or other ignition problem. HTH.

That's what I was looking for, Thanks

[EkuJustice]

For cheap send it off to bill springfield. You will be very impressed with the work he does. He cleans the stock parts up a ton and makes it a pretty darn good trigger. I use the JARD in my competition guns but one of his in the SBR and stuff

[StealthyBlagga]

Rather than sending it off to a gunsmith (which is spendy and teaches you nothing except how to open your wallet), I would advise you install the JP trigger yourself in conjunction with a lightened GI hammer... that's what I run in the picture above and it's about as good a trigger as you will find in any 3-gun rifle. The biggest improvement comes from the JP trigger upgrade - while a JP lightened hammer is nice, it's not really significantly better than the lightened GI hammer IMHO. If you are on a really tight budget, the JP yellow springs will reduce the pull weight without compromising reliability.

Edited by StealthyBlagga, 03 September 2009 - 08:12 AM.

[chp5]

The photo below shows how much I removed from my standard AR15 hammer. This rifle has a JP trigger with yellow springs. I don't recall EVER having a light strike or other ignition problem. HTH.

That's it! That's what I do to all my ARs that don't have aftermarker trigger. An excellent $10 trigger job.

[Middle Man]

Yep, I have a Cav Arms lower that I bought from a fellow forum member that had a GI hammer lightened in the same fashion by Mr. Benny Hill. It's all polished and neat where the hook was removed. It has run flawlessly every month since March.

[MemphisMechanic]

Here's what I did to the rifle I just built. Works great so far. The trigger feels like a nice, crisp 4 pounder to me.

Spend the money. It's worth it.

http://pirate4x4.com...ad.php?t=817298

[wsimpso1]

I bobbed two hammers like the one at the top over ten years ago, and they have never failed to fire, except when ammo was not present...

Billski

[tk4]

Does the bobbed hammer improve ignition and decrease the trigger pull weight, or do you use the jp springs to decrease the trigger pull weight and then bob the hammer for better ignition with the reduced springs? Someone please help me understand this before I start monkeying with my triggers.

[HRider]

The lighter springs decrease pull weight. The lighter hammer spring probably doesn't accellerate the stock (uncut) hammer as fast as the bobbed hammer. I don't know if striking force is affected (heavy and slow as compared to light and fast). I have rifles with JP springs and uncut hammers and some rifles with JP springs and bobbed hammers. Even when using surplus ammo, I have not had a failure to ignite (in 5.56/.223 rifles) with many thousands of rounds fired. The primer strikes look the same between the two. The bobbed hammer feels a little better on the trigger pull due to there is less mass to overcome as you pull the trigger (if you open the gun and dryfire it you will see that the hammer is pushed back a little before it falls).
These are just observations of mine, I am definately not a gunsmith.
Hurley

[TMC]

Does the bobbed hammer improve ignition and decrease the trigger pull weight, or do you use the jp springs to decrease the trigger pull weight and then bob the hammer for better ignition with the reduced springs? Someone please help me understand this before I start monkeying with my triggers.

The ligher hammer spring makes for a ligher trigger because there is less force on the engagement surfaces. With a floating firing pin hammer speed is everything for reliable ignition. A lighter hammer spring cannot accelerate a heavy hammer as well so you need a lighter hammer to compensate. With that said I shot a mil-spec. trigger group with JP springs for years and never had any ignition problems with commerical or reloaded ammo however some military surplus would not fire.

[EkuJustice]

http://www.triggerwork.net/

Send your trigger group and 50 bucks shipping included and it comes back in about a week , with a bobbed hammer, JP springs and feels MUCH better than the factory trigger. I have tried just the springs in the past and it dosen't feel near as nice as when he gets done with one. Had one put in my SBR and am very impressed with it.

[AlamoShooter]

ON the Bobbed hammer thing I don't know nothing, but The lighter hammer in some games is used to cut down on "lock time" the Time it takes the hammer to break and fall and hit the firring pin.
If you are holding for a long range shot a good shooter can see the sights move calling the shot difference in when the trigger was pulled as to ware the sights were when the gun fired.

Lock time diff in firring an off hand shot with a bolt gun compared to an off hand shot with an AR is - Big!-

it could be argued that 90% of shots 3gun have )0( lock time factor.

Edited by AlamoShooter, 13 December 2009 - 10:05 PM.