Home Forums Hunting & Shooting Ask The Gunwriters How high for the safe trigger "Drop test"

I like light trigger pull weights on my rifles, as long as they are safe. I have read a lot about this but nothing appears to be standardized as far as height of drop, surfaced dropped on to (wood floor, tile floor, concrete etc.) and what kind of, if any padding is used. I believe for this safety test to be valid, there should be some kind of guide lines to go by. Maybe trigger manufacturers have standards for this. I have not found anything yet. Thanks, RJ

I would like to add that on my "drop tests", which were non standard.the Pre-2008 Winchester M70, adjusted to a 2 pound pull weight, consistently failed when the rifle was dropped at a height of 12" on a tile floor with a 1/4" rug. Doing the same test under the same conditions with my Ruger M77 and 2 tikka T3's with 2 pound pull weights, these triggers will pass. I am sure this is because the M70 trigger is a very heavy lever, pivoting from the top of the lever and inertia wins out. The other rifles have trigger levers that pivot from the middle, so you have about as much inertia keeping the sear engagement in tact as the inertia trying to disengage the sear and therefor they pass this particular drop test.
I am just wondering if my drop test is too high or should it be higher? Also, is the padding material on the floor what I should be using and is it thick enough? RJ

May I recommend the Savage Accu-Trigger? Failsafe design rather...

Thanks for your recommendation but that does not address the question in my original post. RJ

That is true. I have reservations about inertia testing triggers the way you describe, because it might take other components (rifle stock, scope, mounts...) our of their performance envelope.

Yet rifles do get dropped and with no control over from what height nor onto what surface.

I have no idea on standards. But, any bump test that will cause a trigger to fail on a hunting rifle suggests it is to light. Murphy's Law comes to mind.

There is a SAAMI standard drop test:

https://saami.org/wp-content/uploads/2019/01/SAAMI-Z299.5-Abusive-Mishandling-Approved-3-14-2016.pdf

4' drop onto a rubber matt with the rifle in a "safe carrying condition ". To me this means the safety is "on" if so equipped.

Also states this test does not apply to any rifle designed to have a trigger pull of less than three pounds.

I've tried a similar test and found my bolt rifles pass with the safety on and few pass with the safety off unless the trigger pull is set to over 5 lbs.

Sorry, telling you what we want to say instead of what you asked for is standard Internet operating procedure.

There should be a certain amount of functional ruggedness to things like firearms, but this is like saying that guys leave their guns sitting on top of their cars, so guns should get tested by dropping them onto asphalt at 60 mph.

I hunted deer and antelope as a youngster with my father's guns. He let me carry them with the caveat that I didn't bang them up. I figured out pretty quick how not to drop a rifle, and how to put my body between the ground and the rifle if I tripped and fell. Several decades later, I've still never dropped a gun. I came off the back of an ATV a few years ago, fell about 10 feet, and still found a way to get the rifle off my shoulder and in my hands before I hit the rocks. Pretty cool how well a simple intention works.

That's some funny stuff right there, I don't care who you are!

Section 7 of the above SAAMI report contains their protocol for a "Jar Off" test:


7. Jar-OffTest
7.1. Applies to: Rifles, Shotguns and Handguns
7.1.1. This test simulates the abusive impacting (bumping) of the firearm against a hard surface with the firearm in a condition of maximum readiness.
7.1.2. With the firearm cocked and in the ready-to-fire condition (Safety "Off") the firearm shall be capable of passing a jar-off shock equivalent to being dropped from a height of twelve (12) inches (0.305 m) onto a 85±5 Durometer (Shore A) rubber mat, one (1) inch (2.54 cm) thick, backed by concrete. The mat and concrete shall be large enough so that when the gun is dropped it will fall completely within the perimeter of the mat. The drop height shall be measured from the surface of the rubber mat to the lowest point on the firearm. The gun shall be caught after its first bounce from the mat so that it strikes the mat only one time. The firearm shall be re-cocked and reset in the ready-to-fire condition after each drop or a separate firearm may be used for each drop. As an alternative to free dropping, other methods may be substituted if they provide equivalent impact characteristics.
7.2. Criterion - The firearm shall not fire a chambered empty primed case of its designated cartridge when tested in accordance with this procedure. In the case of a multi-chambered gun, the primed case(s) shall be in the chamber(s) directly in front of the firing pin(s). Parts breakage or other damage resulting from drop testing does not constitute failure as long as the empty primed case does not fire and the firearm can be unloaded safely after each drop.
7.3. Test Procedure - The firearm or firearms shall be dropped in such a way as to cause them to strike the rubber mat surface one time only in each of the following attitudes:
a) Barrel vertical, muzzle down.
b) Barrel vertical, muzzle up.
c) Barrel horizontal, bottom up.
d) Barrel horizontal, bottom down.
e) Barrel horizontal, left side up.
f) Barrel horizontal, right side up.
4
7.3.1. The test shall be conducted with the trigger pull force set at the minimum force specified by the manufacturer.
7.3.2. The test shall be conducted with the magazine, clip or remaining revolver cylinder chambers fully loaded with dummy cartridges and locked in place.
7.3.3. The test shall be conducted with firearms of minimum and maximum weight configurations of a given model, including weight variations introduced by accessories cataloged by the manufacturer.

That's good stuff there 405wcf. Thanks for posting it.
I know you should never drop a rifle or fall with it banging against whatever, if at all possible. But believe me if you hunt enough in the mountains in mud, ice and snow conditions that I do, you WILL go down and very possibly be separated from that rifle. and when you are separated from that rifle, you will have no control of how it impacts the surroundings.
Thanks for everyones input. RJ

My test is to put two gloves on my right hand for extra padding, close the bolt, then lift it up just short of uncocking, and slap the handle back down.

I do that a minimum of ten times w/o "going off", before I feel confident in the adjustments.

If the FP falls before 10, adjust the trigger, and do it again.

I'll also flip the safety on & off several times during the test as well.

Works for be, and beats throwing my guns around.....

My check is somewhat similar to aalf with slapping the bolt down hard.

I rapidly operate the bolt by pulling it all the way back, rapidly running it forward and slamming it down when closing it. I do this for 10 times, if the bolt overrides the trigger without catching it I readjust the trigger. If it catches the trigger for all 10 times then it is good to go.

drover

There's more to setting a trigger for safety than the drop test. Sear engagement and spring pressure - you may have a trigger that is safe when it is clean and in the shop. But dust/dirt/grit gets on the sear and if the spring pressure isn't set hard enough to overcome the dirt, you have a unsafe trigger.

I bang the butt of the stock on the floor (concrete covered by a 1 inch padded rubber mat) pretty stoutly about 10 times. I don't drop the rifle. I also slam the bolt home hard a number of times. I've never found a problem. I don't adjust the triggers on my big game rifles much below 3 lbs so I don't really expect any slam fires. The rimfire triggers are lighter but I use the same tests.

I like to really give them a drop so they bounce even. The one offending trigger a Remington would not pass even a soft 12" drop. This one I screwed up and the screws stripped when extracted and the trigger seemed like pot metal, not at all like the other walker triggers I had adjusted successfully before. Even my talented gunsmith could not fix this one, fine with me and an excuse to get a Jewell.

This is a bizarre thread.

Is the OP's overall goal to determine a "safe" trigger pull weight specifically for when slamming the bolt home (say if you jump a deer unexpectedly) or from accidentally dropping a rifle, (say when out hunting and you slip on the ice)? If the latter, which I suspect it is based on post 15765085, it'll fall from a hell of a lot higher than 12" and likely not hit a padded surface. That, and there are so many variables at play especially with sticks and brush grabbing everything (including the trigger) that I see no valid comparison. If the point is to keep a round from going off when slamming a bolt home, "testing" the trigger pull by dropping the rifle 12" makes no sense to me. I don't think there is any standardization of parameters in either scenario, but I guess I have never looked into it.


I am a 100% cold chamber kind of person, but that is a different discussion.

Want to know if the safety is good or there won't be a negligent discharge? Hold that rifle two feet up and SLAM that sucker on its butt on concrete. Now if you don't want to do that, keep the chamber clear until it is time to shoot.