homemade trigger pull tester

davem · February 23, 2014, 01:39 PM

Gunsmiths use a nice, especially made spring powered device to test the trigger pull on a firearm. Can I get a reliable result using a bent coat hanger and known weights attached?

James K · February 23, 2014, 02:00 PM

Sure. I have even seen a five pound sack of sugar used to test a trigger pull; a bit awkward, but it worked.

But if you do many tests, I suggest buying a trigger pull gauge and use the sugar to make cookies.

Jim

Dixie Gunsmithing · February 23, 2014, 02:17 PM

The cheaper pull scales are not that good, as most do not have a way of recording the weight. The better ones have a recording device, but the best is a gauge set with different weights, or a good digital that can accurately record when the sear gives way.

Bob Dunlap used an expensive, recording, torque meter on his videos, but it would make an excellent gauge. It simply had an arm attached to the shaft, and when enough weight was applied, it held the reading on the dial. These are very expensive, though.

dbc3 · February 23, 2014, 02:21 PM

I was thinking of making one out of a fish scale. Just hook to trigger and pull gradually untill trigger breaks.

davem · February 23, 2014, 02:44 PM

Well I was thinking of bending a metal coat hanger and attach small barbell plates, 1 1/4 lb, 2 1/2 lb (both- 3.75 pound) to get a general idea. The reason I asked was an issue of momentum. If you hold the rifle steady and start pulling on a spring powered scale it will increase pound by pound until the trigger fires whereas if you do it my way, you set the thing up with a set weight and then hold the rifle- muzzle up and slowly let go of the weight, if the trigger doesn't fire with 2 1/2 pounds- the pull is heavier whereas if it fires at 3.75 pounds- then the pull is lighter, and then I would add smaller known weights to get a precise measure but the thing is, all the weight is present and slowly let go while the spring has an ever increasing force (momentum?) and I was wondering if the two different methods would produce different results? I'm pretty sure either is okay but just thought I better ask.

**Unclenick** · February 23, 2014, 03:16 PM

Davem,

You can get different results because of muscle shake and spring bounce. Also, the spring types usually have an indicator they drag along to indicate final weight, but dragging it adds to the result. Peak reading electronic scales can be fooled by inertia.

All trigger measuring at matches is done with trigger weights rather than spring scales, though here, again, a shaky lift of the gun can cause a false low reading. Here's what I did: I made my own trigger weight rod from a 3' piece of 3/16" music wire as is sold in hobby shops for making model airplane landing gear struts. I put it in a vice and heated it with a torch and used a hammer to make the bends. I formed a hook on the bottom, a dogleg to dodge around rifle stocks up above it, and a right angle on top to insert into the trigger guard. I trimmed it with a Dremel tool until that top segment balanced horizontally about three quarters of an inch in from the end. I used a 1" by 3/16" bore Nylon spacer from Lowe's over that last part as a roller and a press nut from that same source over the end to keep the roller from slipping off. I have a lathe, so I grooved the roller for triggers, but that's not required.

To use it, I hook the handle of a gallon milk jug with the bottom and find what level of water doesn't quite pull the trigger when I lift the rifle against it. I then set the tip of the butt stock on the edge of a bench, to take the hand shaking out, and use a narrow spout watering can to add water slowly until the trigger just breaks. I weigh the jug and other parts of the apparatus. I then try to lift that weight with the cocked rifle the way a match official does it to see whether I can get away with it or not. Often the normal small muscle tremors trip it, so I add water, about 2% of the previous weight at a time until I can lift it. Then I weigh it again. That tells me about what a match official is going to pass and what he won't. A gallon of water weighs about 8.3 lbs, so it's usually enough.

The apparatus with empty milk jug weighs 14.5 ounces, so that puts it out of the running for benchrest and free pistol triggers, but it does just fine above that.

Sierra280 · February 23, 2014, 03:23 PM

Wow, everyone is way overthinking this one. I made a trigger pull gauge FAR more accurate than anything that has a spring. I suppose I will share my secret.

Mount rifle securely, muzzle straight up at very edge of bench or counter (I used a sticking out corner of my bookshelf). Got medium size lightweight plastic food container (the one I usually pack lunch in) and a piece of plastic baling twine (strong/lightweight) nylon rope would also work. Weighed them both on the kitchen scale-recorded the weight. Cocked the rifle, Looped the twine around the trigger, then started adding water from a graduated measuring cup. 1 fluid ounce of water weighs 1 ounce!!! Added water 1 ounce at a time until the trigger went click. Tada!! Exact trigger pull weight found. Far more accurate than anything else I've found.

**Unclenick** · February 23, 2014, 03:30 PM

Sierra280,

A fluid ounce of water does not weight one ounce until it is just coming to the boiling point. At room temperature it weighs 1.043 ounces because the cooler water is more dense.

The reason for the wire systems that avoid contact with the stock is to avoid string friction with the sides of the stock that causes the result to be a little light and that can influence the angle of the pull on the trigger. The trigger is a lever arm, so the pull varies with how far out on that lever you contact it. If contact isn't allowing the pull to be straight down as the range officer will measure it, you won't get the same result.

Sierra280 · February 23, 2014, 04:07 PM

I forgot to add I used a thin slice of a notecard across the trigger to keep the string from contacting the guard. I suppose I will have to account for that extra .043, although figured that was the point of using a volumetric water measurement. So if I measure 2.5lbs I suppose my margin of error would be about 1.72s? (.043x40). Also, what are we calling room temp? As boiling is a function of pressure (not temperature) shouldn't there be a standard atmospheric pressure that's used to define when 1fl oz of water weighs 1 oz? Near boiling doesn't cut it for me (I can grab my vacuum pump and boil water at 50 degrees Fahrenheit).

**Unclenick** · February 24, 2014, 10:11 AM

Well, I remembered a digit incorrectly. At 72°F a fluid ounce would be 1.041 ounces by weight. So you would have:

16 × 2.5 × 1.041 = 41.64 ounces or about 2.6025 lbs.

That's an extra 1.64 ounces. It's not the kind of difference you can feel with your finger, even though it can be measured. Human nerve endings have logarithmic sensitivity and a 10% change is about the smallest change in pressure they can notice. You can try this on scales. Hold down about 9 ounces on a postal or a kitchen scale, then increase it to 10 ounces and you'll see you can just barely tell the difference. Same with going from 9 lbs to 10 lbs on a bathroom scale.

The issue isn't with practical feel or we wouldn't use weights to check triggers, but just go by feel. The measurements come into play either when the there is a known lower limit for a particular trigger mechanism, or when you go to a match with a minimum trigger pull rule or have a legal requirement of some kind to meet. In those instances you really want to measure the trigger the same way as the person who is going to check your trigger's compliance will, or you may get a different result.

As to water, we all learned in school that a cubic centimeter of pure, outgassed water weighs a gram. As standards have gone from physical references to defined characteristics (with mass defined by the force required to achieve a certain rate of acceleration, for example), and our ability to measure tiny quantities has improved, the old values have sometimes changed by small amounts. The density of water is one of them. Water is at its highest density at 3.985°C. Above that it expands gradually and below that temperature it starts the expansion that will increase more abruptly as it turns to ice.

At 39.17°F (39.85°C) water is at its maximum density of 0.999975 grams/cc. At that temperature a fluid oz weighs 1.04315 ounces. At 72°F the density drops to 0.9977228 gm/cc, giving a weight of 1.04080 ounces/fluid ounce. At 211.38°F, it is 0.9586110 gm/cc, giving 1.0000 ounces/fluid ounce.

There is a good water density v. temperature calculator, here.

1 fl_oz=29.573531 cc's

Dixie Gunsmithing · February 24, 2014, 10:27 AM

I wanted to show the below force gauges, so one would know the difference between a good force gauge, and the cheaper trigger pull gauges, manual and digital. The digital can be had push/pull, or side pressure. These gauges, though, are generally metric, but some my have an imperial setting for pounds and ounces. These gauges would be the most precise, with logging/recording.

FG3 by matneyw, on Flickr

FG2 by matneyw, on Flickr

FG1 by matneyw, on Flickr

**Unclenick** · February 24, 2014, 10:49 AM

At a law enforcement equipment show one time I saw the TriggerScan demonstrated. It uses a stepper motor to draw the trigger back, eliminating human muscle tremor influence on the final result. Because muscles don't fire perfectly smoothly, small tremors lurch the scale force by small amounts, causing a high bias on readings of any hand operated instrument. The machine eliminates that and provides an analytical tool for diagnosing trigger pull (the resulting plot).

James K · February 24, 2014, 02:57 PM

Everybody needs a million bucks worth of high tech laboratory equipment to measure a trigger pull. Or not.

Jim

davem · February 24, 2014, 06:02 PM

Okay everybody, I never thought about user error on a spring. The bent coat hanger- the way I figured it, if I used a string the string would contact/rub against/be supported by- the trigger guard and might give a false reading so the coat hanger is bent so as to contact only the trigger and "hang free". The way I do it is attach a weight, stand the rifle up and slowly let go of the weight and see if the weight trips the trigger. If not, I take off the coat hanger and add a little more wieght and try again.
Sounds like my method is actually better than a spring pull. I asked because I wasn't sure.

Garycw · February 24, 2014, 08:51 PM

I use a little simpler home device that's always worked for me. It works so well I will most likely continue using it for ever. It's my trigger finger. It works like this ... If it feels heavy to me I lighten it. Too light... I adjust it a little heavier. Works every time very well.

Dixie Gunsmithing · February 24, 2014, 10:15 PM

I actually don't think you need them that precise, but some folks do. I just stick with my weight set. Though, if you do want one, a good used version can be had from eBay, still in calibration, and for a good price. Just do a search for Force Gauge, or Dynamometer.

One would be surprised at how particular on preciseness some target shooters can get. Way beyond what I consider it, to be sure.

Dixie Gunsmithing · February 24, 2014, 10:38 PM

davem,

There is a set of shop drawings, from Uncle Sam, on building a good set of weights and how to make a matching rod for a military set used in armorers shops, but I can not think of which field manual they are in, but maybe others here may remember? Maybe it is in the 1911 field manual, or the one with all the shop tooling in it?

**Unclenick** · February 25, 2014, 10:17 AM

Again, for practical purposes, I think you just want to approximate whatever method might be used to check your gun at a match or for compliance with the rules or compliance with regulations. Read the rules or regulations to learn what that is.

I can see how a gun designer or manufacturer or perhaps even a police department armorer, for liability reasons, might want something like the computer gadget linked to in my last post. But if you measure something on that and then go to a match where an R.O. uses the NRA approved standard trigger weight set, he will likely get a slightly lower reading due to inertia from the weights during lifting and to small muscle tremors.

If your purposes are just personal curiosity, then most any method you come up with that produces a fairly consistent result is probably fine. When I first started learning to turn 1911's into target pistols, I just nailed two scrap 2×4's at a right angle to sit upright like an L about eight inches tall, and at the inside top of the L drilled a hole for a half inch dowel rod to serve as the trigger finger. I'd set this on the bathroom scale, zero the scale, slip the pistol trigger guard over the dowel and push down slowly, watching the scale to see what it read when the hammer fell. Crude, but after several careful passes, averaging the results probably resolves a quarter pound pretty well.

Dixie Gunsmithing · February 27, 2014, 05:15 PM

I ran across this in the M1 Garand field manual.

TPW by matneyw, on Flickr

tobnpr · February 27, 2014, 09:41 PM

I have a bunch of 4 oz., and 8 oz., egg sinkers for bottom fishing the Gulf...

Take 4 of the 8 oz. sinkers, loop them on a piece of thin fishing leader wire (natch), hang the loop on the trigger, adjust until sear releases. Voila...2 lb. trigger. Adjust weights as needed. 'Course, if you want a 5 lb trigger, a barbell weight would be more convenient

Clark · February 28, 2014, 11:52 AM

I have force gauges now, but for a long time I would tie a coffee can to a string that pulled down on a gun pointing up. I would add more nuts and bolts until the trigger tripped. I would weigh the can of nuts and bolts.

I have video about trigger mods for the Mosin Nagant.
I use force gauges 2:55 into the video.
http://www.youtube.com/watch?v=DPn8IdNJ_SE

davem · February 28, 2014, 01:13 PM

Well, I was going to do it in reverse. I want a 3 1/2 pound pull. It is a Remington 700 and you are not supposed to go below 3 lb on the pull. So...I was going to take a 3 1/2 lb weight, take it to the PO to have them weigh on their scales to be sure, then adjust the triger until it just fired with that amount of weight.

Dixie Gunsmithing · February 28, 2014, 01:25 PM

Clark,

I notice you did that correctly in obtaining two readings, though I generally use three, and figure the mean value, or average (somewhere in between the readings). However, a good force gauge is generally repeatable, or very close each time, so the readings are not off by very much at all.

I don't use one much, like I said earlier, just use a weight set on a trigger, but to do what you were doing, a force gauge is much better.

For those reading, who want to know how to calculate the mean, just add all the readings together, and divide by the number of readings you took.

2.1 lb + 2.2 lb + 2.3 lb = 6.6 lb., then 6.6/3 = 2.2 lb.

guncheese · March 1, 2014, 07:02 PM

a gallon jug
a cut up plastic coat hanger
and a harbor freight 11 pound digital scale (got it for $14)

add water till the hammer drops
back off the water till it doesnt
creep back up till it drops
weigh the jug
pour out the water
weigh the jug
subtract 2nd weight from the first
bingo pull weight!!!!

243winxb · March 2, 2014, 08:03 PM

Homemade trigger pull tester. Coat hanger-light weight tin lid-4-1lb Lyman bars-1 box 240gr bullets=Trigger Weight Tester. The coat hanger must rest on the trigger at the same area each time, or reading will be different. Get close with the 1 lb Lyman bars, then add 240gr bullet, till hammer drops. I have measure as low as 9 oz on a free pistol already.

February 23, 2014, 01:39 PM	#1
davem Junior member Join Date: October 4, 2004 Posts: 458	homemade trigger pull tester Gunsmiths use a nice, especially made spring powered device to test the trigger pull on a firearm. Can I get a reliable result using a bent coat hanger and known weights attached?

February 23, 2014, 03:16 PM	#6
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Davem, You can get different results because of muscle shake and spring bounce. Also, the spring types usually have an indicator they drag along to indicate final weight, but dragging it adds to the result. Peak reading electronic scales can be fooled by inertia. All trigger measuring at matches is done with trigger weights rather than spring scales, though here, again, a shaky lift of the gun can cause a false low reading. Here's what I did: I made my own trigger weight rod from a 3' piece of 3/16" music wire as is sold in hobby shops for making model airplane landing gear struts. I put it in a vice and heated it with a torch and used a hammer to make the bends. I formed a hook on the bottom, a dogleg to dodge around rifle stocks up above it, and a right angle on top to insert into the trigger guard. I trimmed it with a Dremel tool until that top segment balanced horizontally about three quarters of an inch in from the end. I used a 1" by 3/16" bore Nylon spacer from Lowe's over that last part as a roller and a press nut from that same source over the end to keep the roller from slipping off. I have a lathe, so I grooved the roller for triggers, but that's not required. To use it, I hook the handle of a gallon milk jug with the bottom and find what level of water doesn't quite pull the trigger when I lift the rifle against it. I then set the tip of the butt stock on the edge of a bench, to take the hand shaking out, and use a narrow spout watering can to add water slowly until the trigger just breaks. I weigh the jug and other parts of the apparatus. I then try to lift that weight with the cocked rifle the way a match official does it to see whether I can get away with it or not. Often the normal small muscle tremors trip it, so I add water, about 2% of the previous weight at a time until I can lift it. Then I weigh it again. That tells me about what a match official is going to pass and what he won't. A gallon of water weighs about 8.3 lbs, so it's usually enough. The apparatus with empty milk jug weighs 14.5 ounces, so that puts it out of the running for benchrest and free pistol triggers, but it does just fine above that. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 23, 2014, 03:30 PM	#8
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Sierra280, A fluid ounce of water does not weight one ounce until it is just coming to the boiling point. At room temperature it weighs 1.043 ounces because the cooler water is more dense. The reason for the wire systems that avoid contact with the stock is to avoid string friction with the sides of the stock that causes the result to be a little light and that can influence the angle of the pull on the trigger. The trigger is a lever arm, so the pull varies with how far out on that lever you contact it. If contact isn't allowing the pull to be straight down as the range officer will measure it, you won't get the same result. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 24, 2014, 10:11 AM	#10
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Well, I remembered a digit incorrectly. At 72°F a fluid ounce would be 1.041 ounces by weight. So you would have: 16 × 2.5 × 1.041 = 41.64 ounces or about 2.6025 lbs. That's an extra 1.64 ounces. It's not the kind of difference you can feel with your finger, even though it can be measured. Human nerve endings have logarithmic sensitivity and a 10% change is about the smallest change in pressure they can notice. You can try this on scales. Hold down about 9 ounces on a postal or a kitchen scale, then increase it to 10 ounces and you'll see you can just barely tell the difference. Same with going from 9 lbs to 10 lbs on a bathroom scale. The issue isn't with practical feel or we wouldn't use weights to check triggers, but just go by feel. The measurements come into play either when the there is a known lower limit for a particular trigger mechanism, or when you go to a match with a minimum trigger pull rule or have a legal requirement of some kind to meet. In those instances you really want to measure the trigger the same way as the person who is going to check your trigger's compliance will, or you may get a different result. As to water, we all learned in school that a cubic centimeter of pure, outgassed water weighs a gram. As standards have gone from physical references to defined characteristics (with mass defined by the force required to achieve a certain rate of acceleration, for example), and our ability to measure tiny quantities has improved, the old values have sometimes changed by small amounts. The density of water is one of them. Water is at its highest density at 3.985°C. Above that it expands gradually and below that temperature it starts the expansion that will increase more abruptly as it turns to ice. At 39.17°F (39.85°C) water is at its maximum density of 0.999975 grams/cc. At that temperature a fluid oz weighs 1.04315 ounces. At 72°F the density drops to 0.9977228 gm/cc, giving a weight of 1.04080 ounces/fluid ounce. At 211.38°F, it is 0.9586110 gm/cc, giving 1.0000 ounces/fluid ounce. There is a good water density v. temperature calculator, here. 1 fl_oz=29.573531 cc's __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 24, 2014, 10:49 AM	#12
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	At a law enforcement equipment show one time I saw the TriggerScan demonstrated. It uses a stepper motor to draw the trigger back, eliminating human muscle tremor influence on the final result. Because muscles don't fire perfectly smoothly, small tremors lurch the scale force by small amounts, causing a high bias on readings of any hand operated instrument. The machine eliminates that and provides an analytical tool for diagnosing trigger pull (the resulting plot). __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 23, 2014, 02:00 PM	#2
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Sure. I have even seen a five pound sack of sugar used to test a trigger pull; a bit awkward, but it worked. But if you do many tests, I suggest buying a trigger pull gauge and use the sugar to make cookies. Jim

February 23, 2014, 02:17 PM	#3
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	The cheaper pull scales are not that good, as most do not have a way of recording the weight. The better ones have a recording device, but the best is a gauge set with different weights, or a good digital that can accurately record when the sear gives way. Bob Dunlap used an expensive, recording, torque meter on his videos, but it would make an excellent gauge. It simply had an arm attached to the shaft, and when enough weight was applied, it held the reading on the dial. These are very expensive, though.

February 23, 2014, 02:21 PM	#4
dbc3 Member Join Date: December 16, 2013 Location: New Hampshire Posts: 46	I was thinking of making one out of a fish scale. Just hook to trigger and pull gradually untill trigger breaks.

February 23, 2014, 02:44 PM	#5
davem Junior member Join Date: October 4, 2004 Posts: 458	Well I was thinking of bending a metal coat hanger and attach small barbell plates, 1 1/4 lb, 2 1/2 lb (both- 3.75 pound) to get a general idea. The reason I asked was an issue of momentum. If you hold the rifle steady and start pulling on a spring powered scale it will increase pound by pound until the trigger fires whereas if you do it my way, you set the thing up with a set weight and then hold the rifle- muzzle up and slowly let go of the weight, if the trigger doesn't fire with 2 1/2 pounds- the pull is heavier whereas if it fires at 3.75 pounds- then the pull is lighter, and then I would add smaller known weights to get a precise measure but the thing is, all the weight is present and slowly let go while the spring has an ever increasing force (momentum?) and I was wondering if the two different methods would produce different results? I'm pretty sure either is okay but just thought I better ask.

February 23, 2014, 03:23 PM	#7
Sierra280 Junior member Join Date: July 29, 2013 Location: Gardnerville, NV Posts: 569	Wow, everyone is way overthinking this one. I made a trigger pull gauge FAR more accurate than anything that has a spring. I suppose I will share my secret. Mount rifle securely, muzzle straight up at very edge of bench or counter (I used a sticking out corner of my bookshelf). Got medium size lightweight plastic food container (the one I usually pack lunch in) and a piece of plastic baling twine (strong/lightweight) nylon rope would also work. Weighed them both on the kitchen scale-recorded the weight. Cocked the rifle, Looped the twine around the trigger, then started adding water from a graduated measuring cup. 1 fluid ounce of water weighs 1 ounce!!! Added water 1 ounce at a time until the trigger went click. Tada!! Exact trigger pull weight found. Far more accurate than anything else I've found.

February 23, 2014, 04:07 PM	#9
Sierra280 Junior member Join Date: July 29, 2013 Location: Gardnerville, NV Posts: 569	I forgot to add I used a thin slice of a notecard across the trigger to keep the string from contacting the guard. I suppose I will have to account for that extra .043, although figured that was the point of using a volumetric water measurement. So if I measure 2.5lbs I suppose my margin of error would be about 1.72s? (.043x40). Also, what are we calling room temp? As boiling is a function of pressure (not temperature) shouldn't there be a standard atmospheric pressure that's used to define when 1fl oz of water weighs 1 oz? Near boiling doesn't cut it for me (I can grab my vacuum pump and boil water at 50 degrees Fahrenheit).

February 24, 2014, 10:27 AM	#11
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	I wanted to show the below force gauges, so one would know the difference between a good force gauge, and the cheaper trigger pull gauges, manual and digital. The digital can be had push/pull, or side pressure. These gauges, though, are generally metric, but some my have an imperial setting for pounds and ounces. These gauges would be the most precise, with logging/recording. FG3 by matneyw, on Flickr FG2 by matneyw, on Flickr FG1 by matneyw, on Flickr

February 24, 2014, 02:57 PM	#13
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Everybody needs a million bucks worth of high tech laboratory equipment to measure a trigger pull. Or not. Jim

February 24, 2014, 06:02 PM	#14
davem Junior member Join Date: October 4, 2004 Posts: 458	Okay everybody, I never thought about user error on a spring. The bent coat hanger- the way I figured it, if I used a string the string would contact/rub against/be supported by- the trigger guard and might give a false reading so the coat hanger is bent so as to contact only the trigger and "hang free". The way I do it is attach a weight, stand the rifle up and slowly let go of the weight and see if the weight trips the trigger. If not, I take off the coat hanger and add a little more wieght and try again. Sounds like my method is actually better than a spring pull. I asked because I wasn't sure.

February 24, 2014, 08:51 PM	#15
Garycw Senior Member Join Date: May 27, 2011 Location: Ohio-Kentucky - florida Posts: 1,221	I use a little simpler home device that's always worked for me. It works so well I will most likely continue using it for ever. It's my trigger finger. It works like this ... If it feels heavy to me I lighten it. Too light... I adjust it a little heavier. Works every time very well.

February 24, 2014, 10:15 PM	#16
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	I actually don't think you need them that precise, but some folks do. I just stick with my weight set. Though, if you do want one, a good used version can be had from eBay, still in calibration, and for a good price. Just do a search for Force Gauge, or Dynamometer. One would be surprised at how particular on preciseness some target shooters can get. Way beyond what I consider it, to be sure.

February 24, 2014, 10:38 PM	#17
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	davem, There is a set of shop drawings, from Uncle Sam, on building a good set of weights and how to make a matching rod for a military set used in armorers shops, but I can not think of which field manual they are in, but maybe others here may remember? Maybe it is in the 1911 field manual, or the one with all the shop tooling in it?

February 25, 2014, 10:17 AM	#18
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Again, for practical purposes, I think you just want to approximate whatever method might be used to check your gun at a match or for compliance with the rules or compliance with regulations. Read the rules or regulations to learn what that is. I can see how a gun designer or manufacturer or perhaps even a police department armorer, for liability reasons, might want something like the computer gadget linked to in my last post. But if you measure something on that and then go to a match where an R.O. uses the NRA approved standard trigger weight set, he will likely get a slightly lower reading due to inertia from the weights during lifting and to small muscle tremors. If your purposes are just personal curiosity, then most any method you come up with that produces a fairly consistent result is probably fine. When I first started learning to turn 1911's into target pistols, I just nailed two scrap 2×4's at a right angle to sit upright like an L about eight inches tall, and at the inside top of the L drilled a hole for a half inch dowel rod to serve as the trigger finger. I'd set this on the bathroom scale, zero the scale, slip the pistol trigger guard over the dowel and push down slowly, watching the scale to see what it read when the hammer fell. Crude, but after several careful passes, averaging the results probably resolves a quarter pound pretty well. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 27, 2014, 05:15 PM	#19
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	I ran across this in the M1 Garand field manual. TPW by matneyw, on Flickr

February 27, 2014, 09:41 PM	#20
tobnpr Senior Member Join Date: August 1, 2010 Location: Tampa Bay Posts: 4,556	I have a bunch of 4 oz., and 8 oz., egg sinkers for bottom fishing the Gulf... Take 4 of the 8 oz. sinkers, loop them on a piece of thin fishing leader wire (natch), hang the loop on the trigger, adjust until sear releases. Voila...2 lb. trigger. Adjust weights as needed. 'Course, if you want a 5 lb trigger, a barbell weight would be more convenient __________________ Remington 700/Savage Rebarreling /Action Blueprinting 07 FFL /Mosin-Nagant Custom Shop/Bent Bolts Genuine Cerakote Applicator www.biggorillagunworks.com

February 28, 2014, 11:52 AM	#21
Clark Senior Member Join Date: December 4, 1999 Location: WA, the ever blue state Posts: 4,678	I have force gauges now, but for a long time I would tie a coffee can to a string that pulled down on a gun pointing up. I would add more nuts and bolts until the trigger tripped. I would weigh the can of nuts and bolts. I have video about trigger mods for the Mosin Nagant. I use force gauges 2:55 into the video. http://www.youtube.com/watch?v=DPn8IdNJ_SE __________________ The word 'forum" does not mean "not criticizing books." "Ad hominem fallacy" is not the same as point by point criticism of books. If you bought the book, and believe it all, it may FEEL like an ad hominem attack, but you might strive to accept other points of view may exist. Are we a nation of competing ideas, or a nation of forced conformity of thought?

February 28, 2014, 01:13 PM	#22
davem Junior member Join Date: October 4, 2004 Posts: 458	Well, I was going to do it in reverse. I want a 3 1/2 pound pull. It is a Remington 700 and you are not supposed to go below 3 lb on the pull. So...I was going to take a 3 1/2 lb weight, take it to the PO to have them weigh on their scales to be sure, then adjust the triger until it just fired with that amount of weight.

February 28, 2014, 01:25 PM	#23
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	Clark, I notice you did that correctly in obtaining two readings, though I generally use three, and figure the mean value, or average (somewhere in between the readings). However, a good force gauge is generally repeatable, or very close each time, so the readings are not off by very much at all. I don't use one much, like I said earlier, just use a weight set on a trigger, but to do what you were doing, a force gauge is much better. For those reading, who want to know how to calculate the mean, just add all the readings together, and divide by the number of readings you took. 2.1 lb + 2.2 lb + 2.3 lb = 6.6 lb., then 6.6/3 = 2.2 lb.

March 1, 2014, 07:02 PM	#24
guncheese Senior Member Join Date: January 13, 2013 Posts: 128	a gallon jug a cut up plastic coat hanger and a harbor freight 11 pound digital scale (got it for $14) add water till the hammer drops back off the water till it doesnt creep back up till it drops weigh the jug pour out the water weigh the jug subtract 2nd weight from the first bingo pull weight!!!!

March 2, 2014, 08:03 PM	#25
243winxb Senior Member Join Date: July 26, 2011 Location: USA Posts: 1,730	My Homemade Homemade trigger pull tester. Coat hanger-light weight tin lid-4-1lb Lyman bars-1 box 240gr bullets=Trigger Weight Tester. The coat hanger must rest on the trigger at the same area each time, or reading will be different. Get close with the 1 lb Lyman bars, then add 240gr bullet, till hammer drops. I have measure as low as 9 oz on a free pistol already.