Buckhorn sight vs recoil

[Reese-Mo]

Hey... I didn't create inertia. What the hell.... try it why doncha?

[Archer]

All of mine are big end forward including the Winchester 1894s and 1895s. Didn't dig out the 1886 or the Marlins.
Most of them, outside of the Rossi aren't flat for the steps however so the 'notches' may lock into the sight body rendering inertia moot.

The gun is going to try to go backwards and with the big end forward the blade will try to stay put but given the light weight of the blade the inertia force will be small.

IF you turn the blade big end aft the rear sight will be shoving against a vertical step locking the sight and elevator together until the gun stops moving to the rear at that point will the inertia of the elevator keep moving it from under the sight?

Give that the deceleration of the gun is probably gradual compared to the recoil impulse it might be more likely to stay in place bassackwards...

[Sarge]

The whole object of having the elevator's tall end forward is to keep it from getting lost in normal use. I sorta thought this was common knowledge, what with Winchester and Marlin sending them out from the factory like that for 100+ years.

[rjsetford]

Thanks for all these replies, folks. Looks like I've got a bit of experimenting to do over the coming weeks.

I'm tempted to make a few copies of the existing elevator so as not to ruin the original one.

I'll let you know how I get on.

Cheers,

Rich

[Reese-Mo]

Lost in use? If they are slippin forward under recoil they'll get lost for sure!

While inertia may be the catalyst, the culprit is either a sight with no springiness to its arm, or a really poorly formed elevator. The "real" correction is with those.

[HarryAlonzo]

Lost in use? If they are slippin forward under recoil they'll get lost for sure!

Not so. With the tall end forward, the elevator is blocked when it reaches the end of the slot. The sight must be lifted to remove the elevator.

[dlidster]

These photos illustrate what I consider the correct and incorrect way to design the elevator on an open sight and how to help -- if not fully correct -- the one that's not right.

The first photo is of the rear sight on a Browning-92. The elevator is pulled all the way to the rear so all of the "teeth" are visible. Note that the sight has to "climb" over a tooth, then settle back into a lower position as adjustments are made. This sight does not slip out of its settling no matter how severe the recoil.

The second photo is of the elevator as it comes from Rossi and a similar elevator that I've altered. With a sharp triagular file I cut the flat-top steps downward at a 30° angle toward the front. It's not a good as the Browning, but it works.

A note on attention to detail: On the Browning the lower surface of the elevator that contacts the barrel bows slightly inward/upward. So, two points -- front and rear -- are always in contact with the barrel. The lower surface of the Rossi elevator bows outward/downward. The result is just one point is in contact with the barrel providing very little resistance to slipping. (I flattened this lower surface after taking the photo, but the result still isn't a good as an inward bow.)*

You might notice the two elevators came from different MIM molds. They're not identical.

Helpful Trivia: Each step on the Rossi elevator is [about] .03" Because the sight radius on a Rossi R92 with a 20" barrel is 16.5", .01" of adjustment will move the POI 1" at 50 yards. This means each elevator step changes the POI three inches at 50 yards or six inches at 100 yards -- roughly.

Edit: *I felt guilty about being somewhat lazy after reading my own post. So, I took the sight off the R92 and relieved the lower edge of the elevator like that on the Browning-92. With the sight back on the rifle I now can see a hairline of daylight between the barrel and the lower edge of the elevator which now bears on the barrel only at the front and rear.

Rear-Sight-B-92.jpg

Rear-Sight-R-92.jpg

[Archer]

Flat out amazing that they bother to MIM that part. The mold had to run them a serious hunk of change. That would be a perfect item to waterjet out of sheet by the thousands it's a 2D profile part and the only secondary operations you might need to do on it is heat treat and finish. No bending, no machining,

The two of mine that are out of the home defense locker at the moment both have the high spot in the middle. I wonder if that's an artifact of post fabrication heat treatment or if the molds are that screwed up.

[Gunny268]

Archer, merely in jest
My vote would be - door number 2.

[mr surveyor]

I'm still proud of my Daisy pellet gun rear sight elevator ... Rossi could learn something regarding design from them

jd