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Discussion Starter #1
Power Custom supplies 3 different reduced power hammer springs with the Hammer & Trigger kit. Power Custom says the 17lb. spring gives the optimum ignition.
The factory spring is 23lbs. Why go to a reduced power hammer spring when it will increase the lock time? I know it will reduce trigger pull, but going to a lighter trigger spring will also lighten trigger pull. Do you think it is better to stay with the factory hammer spring?
 

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I have read that if you replace your mainspring with one that is no more than 2 lbs. lighter than the factory spring you will not experience any problems with the operation of your Ruger Single-Action revolver. I replaced the mainspring on my Blackhawk with a Wolff 21 lb. spring. I also replaced the trigger spring with a Wolff 30 oz. spring. I really saw an improvement in accuracy compared to what I was able to achieve with the factory springs. The timing of the revolver doesn't seem to be affected and the trigger is not a hair-trigger that can accidently discharge the firearm at the slightest touch. I know that most people say to hone surfaces on the trigger, hammer and sear instead of changing springs. But I don't know enough to do the honing without doing something wrong. Changing the springs was relatively easy and I can always change them back if I need to. Even just a 2 lb. drop in the mainspring made a noticable difference in ease of cocking for my arthritic thumb. I definitely recommend replacing your mainspring with a lighter spring, but a 17 lb. spring may be too light.
 

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Guns-N-Rugers, You just hit on a couple of my favorite subjects .... lock time and trigger pull, as they relate to accuracy. Everyone understands trigger pull and want their triggers to have a light smooth pull. Very few shooters understand "lock time" and don't realize it's detrimental effects.

Let's start with the sear. The sear is actually made up of two parts ... the notch in the hammer and the extension on the trigger. If you look at the hammer notch and trigger extension under a microscope, you will see machine marks that are lines in the metal running across the mating surfaces, which is opposite the direction of movement. When you pull the trigger on a cocked gun, these two surfaces create considerable friction which you can feel and the lighter the trigger pull, the more you feel sear movement (called creep). If the machine marks were cut in the direction of movement, you would barely notice creep. Herein lies the first obstacle to a smooth trigger pull.

The trigger extension tip can be stoned in the direction of movement and buffed to a high polish. This will pretty much eliminate machine marks and minimize the feeling of movement. The hammer notch is a different story. It is a shallow notch that is very hard to access. The surface is so shallow that you can't smooth it in the direction of movement so about your only choice is to use a fine "stone" and reduce the machine marks as much as possible. This can result in disaster if you change the sear angle or take off too much metal. Because the hammer-to-trigger position is very critical, you may find the hammer reaches full cock well before the cylinder latches. Additionally, if the sear angle is changed, you can get "push off" where the hammer can be pushed forward or jarred to unlatch the sear without touching the trigger. Both conditions can be very dangerous. I would highly recommend the hammer notch work be left to a professional with the right tools.

The actual trigger pull weight is a product of three things ... sear smoothness (covered above), trigger spring tension, and hammer spring tension. Ruger uses a very strong trigger spring so you can replace it with a Wolff or Power Custom light spring without compromising function. You can also lift one leg of the factory trigger spring off the stud and reduce trigger tension considerably (called "poor boy trigger job"), however this is not recommended because it can create other problems.

Now for the hammer spring and some "lock time" stuff. Single action revolvers are the most difficult of all handguns to master marksmanship. The gun itself is quite accurate but it's the "human factor" related to lock time (also called post trigger pull) that contributes to inaccuracy. Lock time is the amount of time it takes for the hammer to fall and hit the firing pin once the sear is released by pulling the trigger. Here's some comparisons: a typical bolt action rifle has a lock time of 10-15 milliseconds (.010 to .015 seconds), S&W K-frame revolvers take about 39 milliseconds, a Ruger SA revolver takes a whopping 75 milliseconds. That's because the Ruger SA hammers are very heavy and have a long distance to travel. Weight delays hammer movement and the long throw takes more time to travel. During that 75 ms, your hand can move the muzzle well off the target without even knowing it. Palming the grip (shooting high), anticipating recoil (pulling the muzzle down and shooting low), or poor trigger finger placement (pulling the muzzle to the side), are all things that happen during lock time. The longer the lock time, the more opportunity you have to pull the muzzle off target.

Reducing the hammer spring tension is one of the worst things you can do for overall accuracy. Yes, it does reduce trigger pull but you pay dearly for it in lock time. The ratios are pretty close ... if you reduce the hammer spring tension from 23 lbs to 20 lbs, that would be a 13% reduction ... hardly noticeable in actual trigger pull but here's what it does to lock time. A 13% increase in lock time would make the already long 75 ms about 85 ms. A reduction from 23 to 17 lbs (26%) will increase lock time to almost 95 ms. In my opinion, the hammer spring is the worst place to reduce trigger pull.

You can see first hand the effects of lock time by a technique called skip loading (also called ball-and-dummy). Have a friend load your revolver with a mix of live rounds and spent cases. When you shoot a live round, it's nearly impossible for those lock time bad habits to show up. However, when you get a click on a dud chamber, the muzzle will likely do a swan dive and/or pull to the side. It's very typical for a right handed shooter to pull low left. That's because of poor trigger finger placement, grips that don't fit you, and anticipating recoil.

Grips are very important to accuracy. The standard factory "plow handle" grips seldom fit anyone very well. Buy a set of grips where you can dry fire with minimal muzzle movement. There's nothing wrong with using one set of grips to shoot with and another set for "show-and-tell.

So, there are three conditions to satisfy before you can expect good accuracy ... pre-trigger pull where you hold the gun steady and align the sights. Trigger pull where a crisp pull will prevent you from jerking, and post trigger pull where you need to hold the gun very still to keep it on target. Of the three, a light trigger pull has the least effect on actual accuracy. Creep can drive you nuts because you expect the gun to go bang instead of feeling raspy movement or false sear release. Proper fitting grips help you stay on target while your finger is pulling the trigger and during post trigger pull.

So in conclusion, if you want to optimize accuracy with your SA revolver, here's some tips: replace the trigger spring with a lighter one. Stone and buff the trigger extension half of the sear but don't mess with the hammer notch. Use the factory hammer spring. Get some grips that fit you so you can pull the trigger without moving the muzzle. Practice dry firing until you find the "sweet spot" for your trigger finger ... usually in the middle of your "finger print". Try skip loading and watch your muzzle for movement. Don't dwell on a light trigger pull but strive for a "crisp" pull.
 

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Discussion Starter #4
Thank you, Iowegan. Great info and tips here. I had a feeling that it would make sense not to change to a lighter hammer spring and stay with the factory spring. I will use the PC trigger spring and lightly polish the trigger sear (extension half).
It may be that the ugly black plastic grips that are on the gun now fit my hand the best, even though I do not like the looks of them. I may have Cary C make a nice set for me.
 

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I've been doing what you suggest, skip loading. It sure shows my flinch, the nose drops, no doubt about it. So each shot I have to breathe out to the end of the breath, squeeze the trigger, and forget about recoil. I'm getting better but I'm not there yet...
 

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Guns-N-Rugers, Here's a set of grips I bought for my 45 Colt Vaquero. They also fit my Blackhawks so I put them on before shooting any one of the guns. These are oversized with finger grooves and really fit my hand. My marksmanship is way better with these because I can pull the trigger without the slightest muzzle movement. Besides, they have a larger contact surface with my hand so recoil feels very tame.

 

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Very useful information! Some folks actually install a stronger hammer spring (from the Old Army) in an attempt to decrease lock time and to insure a positive primer strike.
 

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For a five minute no-cost action job, just unhook one side of the trigger return spring. You can either cut it off or just leave it. Then cycle the action and add just a little pressure to the hammer with your thumb as you dry fire the pistol. That's all there is to it.

Try it, you'll be amazed.
 

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............................................ You can also lift one leg of the factory trigger spring off the stud and reduce trigger tension considerably (called "poor boy trigger job"), however this is not recommended because it can create other problems..........................................
Just curious, what other problems could result?
 

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Iowegan,

Excellent !!

I performed your overhaul on my SP101 and I am very happy. I always shoot with at least one empty cartridge to see how I react. Some days it is unbelievable how jump I am. Other days I hardly move .

It is kind of like my golf game.

With my GP100 I was relatively pleased with the trigger and only put in a lighter spring. After about 500 rounds it has smoothed out considerably and I will leave well enough alone.

JRB
 

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rivraton, The unlatched leg of the trigger spring usually drags on the hammer spring. In some cases, it causes the hammer to gag when you cock it. More importantly, the trigger spring will not provide even sear tension. One time you may get a 3 lb pull ... the next time you may get a 4 lb pull. After repeated use, the sear will get worn on one side while the other side is still sharp. This can allow push-off ... where the hammer can release by jarring or being pushed forward. That said .... sometimes the "poor boy trigger job" works just fine and doesn't cause any problems at all.

As a gunsmith, I would never do the PBTJ to a customer's gun. Sooner or later, the customer will see the leg off the stud and get really pissed for paying me to do a "professional" trigger job.
 

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I kinda thought it would be a side thrust issue, as you describe. The hammer interference never occurred to me.
 

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Iowegan
Try skip loading and watch your muzzle for movement.
I have been trying to cure myself of anticipating recoil and twitching. I load all six and then every time I fire a shot I open the loading gate and give the cylinder a turn or two. When you get down to one round remaining to be fired and you get four clicks the anticipation factor goes way up.
Marty
 

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Something else to try/consider is talking to yourself. It sounds stupid, but it works. In basic firearms training they tell you if you anticipate the trigger pull, talk to your self out loud. It works really well for beginners. They recommend saying "Front sight, Front sight, Trigger Squeeze." It helps you to stay focused on the front sight and also keeps your mind off of the recoil/trigger anticipation. It worked with my wife on my P220. Just be aware, folks at the range may look at you a little on the strange side while your talking to yourself.:D
 

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Guesswho, I talk to myself when I'm shooting too but the words are not suitable for this forum. I guess that's why I don't go to public ranges.
 

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Thats Funny. I have them days too.

I try to get in to the "Zone" when shooting. At least for qualifications and such. It makes things so much easier.

I've seen my wife go from missing a tagret at 10 yards to hitting center mass shots consistantly after she "talked to herself". It really helps out beginners or the less expierenced shooter who have issues with jerking the gun around from anticipation.
 

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I am going to experiment by skeletonizing the extremely heavy hammer on my Single Six. I've got a mill and drill press plus time on my hands. It might wind up looking like a hollowed out Bisley hammer. By reducing the hammer mass and maintaining spring loading, its velocity as it travels through its arc should increase and thus reduce lock time. That's just good old high school physics. If that works, the next step is to reduce the hammer spring power until misfires occur and then go back to the power that is still reliable. Last is (GASP) to thin out the transfer bar just a teeny weeny bit to reduce the at rest inertia that the hammer blow must overcome to actually strike the firing pin. The goals are to reduce lock time, reduce hammer spring power commensurate with reliable ignition, and achieve a smoother, lighter trigger pull. Of course all of the contact surfaces will be polished and shims installed on the hammer and trigger pins. It it doesn't work, hammers and transfer bars are are not that expensive.
 

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jcarr, I hate to shoot holes in your concepts but I think you may be off base. First, drilling holes in the hammer will indeed lighten the weight and shorten lock time but it takes velocity plus hammer weight to develop the energy needed to pop a primer. Increasing hammer velocity should counter the weight difference but have a spare hammer available in case it doesn't .... plus holes in a hammer are just plane ugly. Next, break out your diamond drill bits because Ruger hammers are harder than woodpecker lips. You won't do much more than scratch the surface with conventional bits.

I don't think you understand how Ruger's transfer bar design works. Hammers with factory 23 lb springs develop way more striking energy than needed so rather than reduce the hammer's spring tension and increase lock time, Ruger designed the revolver with a heavy hammer spring to reduce lock time. This involves the top step of the hammer striking the frame to dissipate most of the energy, yet still leaving barely enough energy to detonate primers. If you thin the transfer bar, it will cause more energy to be dissipated by the frame and will result in light primer strikes .... plus the trigger won't reset properly. This is a lose, lose, lose, lose situation because trigger pull doesn't change, lock time doesn't change, the trigger won't reset, and you risk light primer strikes. Using a reduce power hammer spring defeats the very purpose of reducing lock time. If you do a before & after, you will find lock time has more influence on accuracy than a light trigger pull. That said, most people prefer a light and smooth trigger pull, even if it doesn't improve accuracy.

If you really want to improve trigger pull .... less creep with less pull weight, There are a few things you can do. The simplest is to replace the heavy factory trigger spring with a Wolf 30 oz reduced power spring. This will cut the factory trigger pull in about half and the only downside is .... you will still feel notable creep. Buffing the sear notch and the trigger extension with a muslin buffing wheel and 500 grit compound will reduce creep notably. Here's a link: WOLFF REDUCED POWER TRIGGER SPRINGS | Brownells

I do not normally recommend this procedure but If you have the tools and mechanical skills, you can use your existing gun as a "test fixture" to refine the sear angle and polish both the trigger extension and the hammer's sear notch. Using the fixture in the below photo with a rubber band connecting the hammer spur to the front of the frame for hammer tension .... pay very close attention to the hammer spur tip as the trigger is pulled ever so slowly. In nearly all Ruger SAs, the hammer cams back slightly as the trigger is pulled. This means you are actually fighting unnecessary hammer spring tension. By changing the sear angle to a point where the hammer neither moves forward or backwards as the trigger is pulled, you can easily reduce pull weight to 3 lbs with virtually no creep, using the factory trigger spring or less than 2 lbs with a Wolf reduce power trigger spring, which is dangerously light. As I noted in an earlier post in this thread, creep (the feeling of sear movement) comes from the rough mating surfaces when hammer spring tension is applied. By "squaring" the sear as noted above, nearly all the creep magically goes away. This will result in a "best case scenario" .... a light, smooth creep free trigger pull without extending lock time. It's also called a professional trigger job and is not ugly.



BTW, the hammer pivot pin is secured by the longer trigger guard screw. The trigger pivot pin is installed backwards so the loading gate spring will secure it. This technique works equally well with Single-Sixes, Blackhawks, Vaqueros, and Super Blackhawks.
 

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Another 11 year old thread resurrection! But WTH, I'm game. Listen to Iowegan, he's Iowan and knows his stuff. In place of lighter springs the factory trigger spring can be bent slightly to reduce weight, and the bend can be adjusted to the desired weight. This is of course in addition to smoothing any surfaces that rub together as Iowegan mentions.
 
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