I bought a 66 and a 629 this year

The 629 has the classic smooth as butter trigger you hear about with Smiths. Its honestly even better than my 586 custom shop they tuned up.

The 66 had a much heavier and a bit of resistance build up right towards the end of the pull. It was smoothish but nothing to write home about.

I finally decided to bust open the 66 and do a little tuning. I just barely put a little roll into the mainspring to try and smooth out that last little bit of resistance towards the end of a DA pull.

Its now as smooth as the 629. Breaks at about 8.5# double action and a little over 3# single action(measured at the very bottom of the trigger). Went and popped a primer in the garage. Loaded up some heavy 38s with winchester primers and then a batch of  heavy 357s with CCI magnum primers. All went off without a hitch.

I cant help but wonder where the floor limit for DA pulls should be. I feel I have to be flirting with it a little bit but it is still popping primers no issue.

What say you?

As long as you're popping primers you're good. I don't mess with springs but I do stone the sides of everything inside my revolvers.

Yeah I was a little hesitant

A little goes a LONG ways on that mainspring

I never touched my 586 springs and one day it just straight stopped popping primers. I remember I pulled it out with my carry load and got like 5 clicks and only 2 bangs. I tried a wilson spring kit after that on it and it would still occasionally get light strikes. Ive had a hard time trusting that gun ever since to be honest. I suppose it could be as simple as the pro shop or whatever maybe took too much off a strain screw when tuning it too but it didnt crop its head for several years of ownership.

I think thats why Im also a little curious if there are any spec floors out there for the trigger pull. Easy to pop a gauge on it every few months to ensure the above doesnt happen to me again.

I was shooting for 9# but landed at the 8.5#. Ive also seen the weight can vary greatly by where you 'pull' the trigger on the gauge so Im assuming most everyone measures from the bottom of the trigger.

It is pretty easy to see which surfaces inside a S&W revolver would benefit from being polished.

I don't like the ideas of cutting springs, changing the angle of the sear, or reducing sear engagement, but polishing is easy to do, and makes a huge difference.   Auto parts stores usually stock 400, 600, 1000, 1200, 1500 and 2000 grit abrasive paper.  When cut into smaller pieces, a sheet of each grit will last a long time.  

I have heard of people using toothpaste as an alternative to abrasive paper, but I have never tried it.

ETA:  While I haven't seen any proof of the idea, I have heard that some folks test firing pin power by holding a penny over the firing pin hole, and if the firing pin puts a dent in Lincoln's head, there is sufficient power in the hammer strike.  Another idea I haven't tested myself though, but it seems interesting.

Back when PPC was popular with police competitors some crazy light DA pulls in the five pound range were possible but then the caveats of only use federal primers etc.
I would say you are pretty close to as low as you should go.

A quick trick to check that 586 ( or any strain screw equipped gun) that misfires is to take a spent small pistol primer pop out the anvil and sandwich it between the tip of the strain screw and mainspring sort of like a cap on the tip of the screw. If misfires go away, you have two choices- leave it that way or get a longer strain screw.
I have had a bunch of S&W’s over the years that I shot with that primer cup strain screw cap

Thanks I think Ill give that a shot. Got a whole lotta dead primers so that should be pretty easy to test.

That's what I do too.

A lot of folks go right at the springs, but getting everything that rubs on anything else nice and smooth reduces a lot of resistance and effectively makes your springs feel lighter. I actually polish the surfaces with Flitz.

Good lubrication helps too.

Guns I carry do not go under 8 pounds and can fire off any primer every time (to date).

My competition guns range from 6 to 8 pounds and are very reliable with Federal primers.

NEVER mess with the mainspring or the strain screw. Clip about 1 (one) loop off of the trigger return spring. That's how I was taught. Sure, you can loosen the strain screw, but don't start grinding on it.

Thanks!

Ill throw a gauge on it here and there to see if it loses tension over time

I polished the bearing surfaces of moving parts (except the sears) in the manner described in the Kuhnhausen manual and show on YouTube. I also installed lighter springs. I have a lighter main spring, and installed the lightest return spring that would work reliably. I think I got the Wilson spring kit.

My double action pull measured around 8 pounds, and my single action pull measured 2.5 pounds. The double action pull is VERY smooth.

These are what Nelson Ford has come up with for factory ammo. The weights are measured by pulling back on the hammer, with the scale, rather than the trigger. He says these will definitely pop hard primers, but you could potentially go a little lighter.

Attached File

Neat

Ill give that a measure and see where mine are stacking up

I appreciate the info as that really helps to give me a baseline

NP. Give Mr. Ford a call if you have questions. He's a well of info.

I wonder why Ford's chart differentiates pre-96 and post-96?

I asummed hammer weight/ design change

Is that when they changed the hammers from the oldschool ones with the nose that was replaceable to the new design with a hammer and a sprung firing pin

Yeah, the newer frame mounted firing pins need a firmer smack. Additional friction, maybe the basic mechanics of hitting a floating object against a fixed object? I'm not sure exactly.