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shooterx10
11-15-2006, 9:07 AM
I picked up Derrick Martin's book, The Complete Guide to AR-15 Accuracy. There's a gunsmithing section in there that talks about lightening the hammer by cutting off the hooked portion to shave weight and decrease lock time.

Has anyone tried it? What kind of Dremel tools did you use and which wheels did you use?

Off topic: What is a good price for Rock River Arms' National Match (NM) trigger?

ocabj
11-15-2006, 9:27 AM
You can get the RRA 2-stage tuned by White Oak for $120.

Adco sells a tuned RRA 2-stage for $100. Not sure who modified it.

C.G.
11-15-2006, 10:04 AM
I picked up Derrick Martin's book, The Complete Guide to AR-15 Accuracy. There's a gunsmithing section in there that talks about lightening the hammer by cutting off the hooked portion to shave weight and decrease lock time.

Has anyone tried it? What kind of Dremel tools did you use and which wheels did you use?

Off topic: What is a good price for Rock River Arms' National Match (NM) trigger?

I've also read some horror stories about people lightning their triggers to the point of unreliability, either no function or almost auto function.

50 Freak
11-15-2006, 10:22 AM
A gentlemen I knew did it to my AR along with a couple of other things. Said it helped him in 3 gun. Not sure how that .00001 mili-second helps, but whatever.

But my trigger pull is very nice for a military trigger group. Have no problems with rounds with tough primers. Wolf works fine.

Only problem is when I put in a Colt 22 conversion kit, the hammer is too light to set of the 22lr. Probably because of the heavier firing pin involved.

ocabj
11-15-2006, 10:24 AM
I've also read some horror stories about people lightning their triggers to the point of unreliability, either no function or almost auto function.

Lightening the weight of the hammer doesn't affect trigger pull weight. All you are attempting to do by doing so is decrease the time it takes the hammer to fall after the sear is tripped when the trigger is pulled to the time it strikes the firing pin.

That said, I personally never tried it. I don't think you'll see much benefit from it. If you're hold is good and trigger pull is proper, then that gain in locktime from a lightening the hammer on a match trigger kit won't mean anything. If the lock time gain is measured in a tenth or hundredths of a second, then maybe. But I think the lighter hammer will result in a gain measured in nano or even pico seconds, which is just too small to make a difference. If anything, the hammer has already been lightened.

Bob Hostetter
11-15-2006, 1:10 PM
Decreasing the hammer weight will decrease the lock time which is the time it takes the hammer to fall and strike the firing pin. If you decide to lighten the hammer make sure you don't go to far or you will get light hits on the primers.

JPglee1
11-15-2006, 1:24 PM
Decreasing the hammer weight will decrease the lock time which is the time it takes the hammer to fall and strike the firing pin. If you decide to lighten the hammer make sure you don't go to far or you will get light hits on the primers.

Or, add a stiffer hammer spring.

Cut the tail of the hammer off with a hacksaw or a sanding disk on a grinder. You can also drill holes in it, or whatever.

I personally want to know its gonna work 100% of the time so I dont mess with defensive weapons, but on a race gun, why not :)

Also, for those who dont know, faster lock time is desirable because it gives less time for you to move (and upset the intended point of impact by moving the point of aim slightly) between the time the trigger is pulled and the time the bullet leaves the barrel...


J

brando
11-15-2006, 2:22 PM
Don't mess with the guts of your AR unless all you're doing is replacing them or polishing contact points (even that should be done with caution). If you want a better trigger pull, get a drop in McCormack setup or replace parts with a decent 2-stage setup.

-hanko
11-15-2006, 3:29 PM
You can get the RRA 2-stage tuned by White Oak for $120.

Adco sells a tuned RRA 2-stage for $100. Not sure who modified it.
THE trigger is White Oak's modified by John Holliger. Period.

If you shoot or are saving NATO ammo for hard times, I'd be wary of any trigger change that lightens the hammer fall...whether it's reducing hammer mass or hammer spring force as NATO ammo uses harder primers. You do want her to go 'bang' every time;)

-hanko

randy
11-29-2006, 4:49 AM
I have a Accuracy Speaks lightened trigger assy. and lightened disconnector spring along with a lightened trigger return spring, on one lower for over 3 years. Never a problem with anything. I've used the McCormik drop in it didn't do it for me to much $$ for what you got even though it was cheaper than my AS. I've used RRA's two stage $75.00 and felt it was a good buy.

Satex
11-29-2006, 7:52 AM
A gentlemen I knew did it to my AR along with a couple of other things. Said it helped him in 3 gun. Not sure how that .00001 mili-second helps, but whatever.


It's just like when you wash your car and all the sudden it feels like a hot-rod!
;)

C9X19
11-29-2006, 8:07 AM
I cut the hammer tail off with no ill effects. The reason I did it was I purchased the JP trigger-group SPRINGS (not a drop in kit, just springs). The power of the springs are reduced-power so I didn't want to have too heavy of a hammer. Despite the fact I haven't put a whole lot of rounds through it (about 500-600), the gun has run just fine. :cool:

TMC
11-29-2006, 9:18 AM
It will decrease lock time but only by a few miliseconds. The AR will never have the lock time of say a Remington 700. IIRC the AR has a lock time of 125 +/- milliseconds and the 700 is 4. Thats a long way to go. That's why most long range shooters do not use an AR type system.

If it makes you feel better then by all means do it. The JP hammer is very small and light and so are his springs. You will not have any problem lighting commercial ammo. Some folks do have trouble with JP's trigger system lighting mil-surplus ammo but I do not.

bu-bye
11-29-2006, 10:31 AM
I cut the hammer tail off with no ill effects. The reason I did it was I purchased the JP trigger-group SPRINGS (not a drop in kit, just springs). The power of the springs are reduced-power so I didn't want to have too heavy of a hammer. Despite the fact I haven't put a whole lot of rounds through it (about 500-600), the gun has run just fine. :cool:


I cut mine as per the JP instructions. Kit came with springs, disconnect and sear but no hammer. I had to mod mine a little. I have had no issues since.

C9X19
11-29-2006, 4:51 PM
I cut mine as per the JP instructions. Kit came with springs, disconnect and sear but no hammer. I had to mod mine a little. I have had no issues since.

Yep. And I've been running Wolf (mix of laquer/poly) just about exclusively through it.