Home Forums Hunting & Shooting Hunting Optics My method for measuring eye relief:

Never cared for this flashlight through the lense, piece of paper bllsht. It's as worthless as paper specs.

My method of measuring "eye relief":

Eye relief is unique to each individual shooter. If you're going to get an injury from the riflescope, itll be from the top surface of the ocular housing. It's gonna hit your eyebrow, bridge of your nose, or slightly above your eye brow, low on the forehead.


So the physical distance that the top surface of the ocular housing is from my face, reigns supreme.


On the leupold 2.5x ultralight, on my rifle, where I get a full field of view in the scope, the ocular housing is 4" away from my eyebrow. This measurement is the only one that matters. No biggie to have somebody take this measurement for yah, as you shoulder the rifle.

On hard recoiling lightweight rifles, like my 416 ruger it's reassuring.

I manage to forget correct eye relief when shooting steep uphill shots from contorted positions. The blood in your eye makes follow up shot challenging.[grin[


mike r

Mike, I've only ever had a scope love-touch my face once. It was a leupold 1.5-5. The little rubber ocular protector was torn, but wasn't enough force to hurt me.

Just as you said: some weird, seated field position on a steep hill, trying to get a steady shot at a bull moose about 500 yds away.

This rifle was light, a cz 550 kevlar carbine in 9.3x62 shooting a feisty handload of 300 grain swift a-frames over 64 grains of MR 2000.

It's these bizarre field positions that we must do, in a split second, to seal the deal.

Since then, I've always been curious about how far a scope is from my face on these light-weight, heavy-recoiling rifles we Alaskans tend to shoot.

I measure from the scope body that will thump you. Look forward to what you find. I guarantee it won't be near 4" at any power.

The older scopes, without a rubber ring on the ocular are the killer. My wife and I took another couple to camp for the weekend and the wife had a .243

One morning she jumped out of the truck to shoot a jackrabbit and was awkwardly using the open door as a rest. Recoil filleted a perfect half moon on her brow, that the local clinic stitched up. What was funny, was it was a small town and everywhere we went, every female would look at her, while pointing at her brow, they'd utter a one word question. "Scope?"

Geeze, poor gal. Did it heal up ok?

The ol' Magnum Eyebrow. I've experienced it a couple times, mostly weird angles. I shot a bear in Canada one year with my vanilla 280 Rem. Ackward angle at the shot. I didn't feel it hit me but as I walked up to the bear, I noticed my neck was warm. I wiped it and my hand came back bloody. Got wacked pretty good. I went back to camp as is. When I walked in the door the look on everyone's face was priceless. I told them I shot a bear and when I got up to it it jumped up and took a swipe at me. Of course it took 5 secs for people to realize is was scope bite. We still laugh at that.

My late uncle’s deer gun was a 20” Ithaca Deerslayer with a K4 (dot reticle) in Weaver Pivot mounts. Scopes on shotguns were a radical idea in those days and lots of people wanted to try it out. As his son says, that scope has a lot of DNA on it….

I’ve been hit, but so far never cut.

You could take 1 shot with the scope against your brow and measure the depth of the cut.

Bwinters: Never heard "it" referred to as "magnum eyebrow" (although that may be appropriate?) I always heard it referred to as "Weatherby eyebrow".
I have only suffered that indignity twice over my 60+ year long stint of centerfire Rifle shooting.
Had to pick a "Weatherby eyebrow" blood icicle off of my cheek one wintry/blizzardly day in Wyoming - got some powder snow between the buttplate of my pre-64 Model 70 Winchester (30/06) and my shoulder. Firing from the prone position, that one nearly knocked me out!
Lessons learned - I hope.
Hold into the wind
VarmintGuy

She did. We got it stitched up on our way to Fredericksburg TX for the day and returned to the blind in the evening. We still chuckle about it, but it was a good gash for sure.

Here's a quote from the guy who helped developed the flashlight method, but was not the first to use it, published a number of years ago:

"Switch on a small flashlight, and gently place the front end against the objective lens of the scope. Hold some flat object about three inches behind the eyepiece. A dot of light will be 'projected' on the object. This is the exit pupil of the scope. Move the object until the dot's as small and sharp as possible, and the distance from the rear of the scope to the object is the eye relief."

Please note that the author said "the rear of the scope," not the rear lens. Which obviously means the eyepiece.

The advantages of this method are that it can measure the "eyebrow distance" without anybody else's help--and it also precisely measures eye relief when a variable scope is set on various magnifications. This often differs somewhat, even in scopes advertised as having "constant eye relief."

Bingo. Just measured a Trijicon 3-9X Huron a couple of hours ago. Pretty close to their specs. Probably doesn't work in Alaska...

John, give me a fkn break. Where a scope renders a clear field of view to a shooter's eye, in relation to the the physical distance from a given shooter's eyebrow, is different for every shooter.

EDM, calm yer fkn hormones bud.

Pure comedy. Write what you measure...

I don't understand what would be so funny about knowing how far away a scope is from your eyebrow, on a heavy recoiling rifle?

I can guarantee you, it's more exact, than this paper/flashlight bllsht. Obviously the naked eye, and the eyebrow aren't at the same depth.

Try it out.......

One way to get a measurement...


- Wrap the rear scope lens housing with a tube of paper or manilla folder about 5+ inches long
- Cut a narrow long "window" into the tube (~1/8 -1/4" wide x 1-2" long with the middle of the window at 3" from the end of the scope.
- Wrap it with a rubber band to loosely secure the tube's position Put your eye brow bone on the end of the tube and move it in or out under you get a full image in the rear lens.
- Measure the distance from the end of the tube, to the end of the scope (through the "window".)
- Get measurements in normal offhand position, and " off the bench" position. It will reveal how much you crawl into the scope with your head/neck.



We would call the brow cut, "scope eye."

This is a nice thread. Very helpful, thanks for sharing.

Col Jeff Cooper's name for being hit by scope: Kaibab eye

No problem. Taking blows to the face from a boxer is nothing. We army gorrillas knocked the sht out of each other in boxing matches, to resolve arguments, so we wouldn't end up in Leavenworth (military prison).

BUT, you take a metal riflescope to a critical spot on your face, from a hard recoiling rifle, not good.

I have taken a blow to that area of my face, in a fall off a roof when a sniper took a pop shot at me. It wasn't graceful. I caught the bridge of my nose off the sharp edge of an air conditioning unit at ground level.

Theres a little flap of membrane behind bridge of your nose that holds back your spinal/brain fluid that cushions your brain. All that fluid came gushing out of my fkn nose.

3 Shoemakers and 1 washed up, frost-bitten prick, can't be wrong about the joys of 2.5x ultralight on a hard recoiling lightweight rifle..........