The Lyman Products catalogue offers a plethora of useful accessories to shooters, gunsmiths and professionals of gun care alike − including reloading instruments, shooting aids and maintenance tools.
Amongst all others, what would seem to be a "niche" product is actually essential in many sports shooting disciplines, as it enables shooters to accurately measure the trigger pull and weight on their guns.
Since the trigger pull and weight are an extremely important factor in accurate shooting, knowing the exact level of resistance that the transfer bar opposes to the trigger pull will enable shooters to adjust the trigger if possible, to modify parts of the trigger group, or to replace it outright.
Lyman's electronic Trigger Pull Weight provides accurate measuring with a maximum error margin of two to 10 grams, depending from the trigger weight; it can be used on triggers whose weight ranges from 2,8 grams (1oz.) to 5,4 kilograms (12lbs.).
The Lyman Trigger Pull Gauge is powered through a 9V commercial battery (not included) and is issued with a user's manual, a practical and resistant cordura Nylon pouch and the notched L-shaped metal bar that attaches to the trigger to measure. The user's manual is in English language only.
The Lyman Trigger Pull Gauge chassis is ergonomically shaped, and the "finger grooves" in its body provide an excellent grip in all circumstances; the display is large enough to remain easy to read in most light conditions.
The device features four orange rubberized buttons: the READY button turns the device off, the CLR button clears the memory from all data, the LBS/GM automatically converts the measurings data from Grams to Pounds and vice-versa, while the AVG button provides an average of the latest 10 measurings.
The device comes with a 15-centimetres long L-shaped metal bar with a threaded end; the shorter extremity is 5-centimetres long and comes with a synthetic black notch that allows the device to interact with the trigger of the gun that's being tested, thus eliminating any interference due to the force applied during the testing.
The threaded end of the metal bar comes with a securing notch, and is meant to be attached to the device through the conic extremity on top of it.
The securing nut allows the direction of the metal bar to be adjusted according to the gun that's to be tested.
Once the metal bar is in place, the user will have to push the READY button to activate the device.
Upon a second pressure of the same button, the Lyman Trigger Group Gauge will let out a sound: it is now ready to be used.
If left inactive, Lyman's Trigger Pull Gauge will automatically switch off after three minutes. The "LO" letters will appear on the display when the battery is low: while it may still provide enough power for the device to activate, low-power operation will not provide accurate measuring.
The Lyman Trigger Pull Gauge is conceived to be used on empty guns (dry-firing); this doesn't mean that users may disregard all basic gun safety rules. Before using the Lyman Trigger Pull Gauge on your gun, double-check that it is empty.
In order to obtain an accurate reading, the Lyman Trigger Pull Gauge's L-shaped measuring bar should be as parallel as possible to the bore axis of the gun being tested. The trigger should be pulled gently, as when dry-firing the gun for familiarization.
The device is extremely sensitive, so any unnecessary pressure will be recorded and provide an incorrect reading.
Special attention should be paid to the trigger overtravel − that being, the short distance that in some guns the trigger will still travel rearward after the gun fired − as it could result in incorrect measurings and readings.
Shooters who are less than familiar with shooting techniques may find this device difficult to use. The manufacturing company also warns that any weight over 5,4 kilograms (12 pounds) may damage the device, so special attention should be paid to the technical peculiarities of tested guns, and the device should be used accordingly: so to speak, in the case of a 1911 pistol, the device should be used only after the grip safety has been deactivated, either by holding it with a proper grip that wouldn't hamper the use of the device itself or with some tape.
When testing guns with a trigger safety ("à la Glock"), the measuring bar should engage the trigger safety itself, or alternatively a few tape should once again be placed on the trigger to deactivate it.
When using the Lyman Trigger Pull Gauge with a double-action revolver, the hand holding the gun should be positioned so that it won't intervere with the revolving cylinder − and be cause of incorrect readings.
Competition shooters know all too well that using the right gun for the right discipline, and with the right trigger pull, may make the difference between loosing and winning a match. An instrument that lets you master the trigger pull and weight averages on your gun can really be the ace up the shooter's sleeve.
So to speak, Lyman's electronic digital Trigger Pull Gauge is so accurate that we actually managed to measure the average trigger pull weight of a TOZ-35 pistol, which is around 158 grams. This device is truly a must-have for professionals of gun care and maintenance and for any serious sports shooter.