Redfield Revolution Accurange reticle subtensions

bobnob

Well-known member
Jan 15, 2016
566
4
NSW, Australia
Thought I'd post my findings on a subtension check I did on a Redfield Revolution 4-12x40 with the Accurange reticle.

I've had this scope on a few rifles, and while I have never been wild about the circle + dot reticle, it has held zero very well and doesn't change POI when power / magnification is changed. It's also compact and light.

Anyway I only checked what the subtensions on the reticle equal on 12x because that's what I use if I have a long range shot.

I shot the subtensions on a 4 odd foot high target with some old Core Lokt ammo at 125y.

Anyway a long story cut short is that the subtensions represented by the bottom part of the circle crossing the vertical is 2.2moa, the dot is 5.2moa and the junction of the duplex post and crosshair is 8.2moa.



Those subtensions will get me out to around 300, 400 and 500y. Having said that the "gaps" between the bottom two aiming points start to get a little too big to be useful. IOW the value of this reticle much beyond 400y starts to become a bit questionable.

Once I worked out the bottom point was near the 500y point I tried a few shots on a 10" high steel plate at 450y from the bench. Putting the top of the duplex post at the bottom of the plate at 450y got me three hits out of three shots. So with a known distance and time to calculate maybe its not the worst arrangement.

Sorry for the poor pics...



Anyway just sharing the drum.

I know, I KNOW... pass the FFs...
 

4th_point

Well-known member
Dec 4, 2013
835
0
Oregon
Definitely a worthwhile test if using dotz, especially with higher magnification and associated parallax.

I've used dotz for holdover with decent results, but mostly 6x scopes with little perceived parallax. A few buds still use dotz with good results but we've seen some inconsistent results due to parallax and higher magnification. Checking subtensions visually and by shooting at 100 is important, but shooting out to the picket distance reveals even more.

For one, dotz can force you to be inconsistent in terms of eye-to-scope alignment. If your 'center' is no longer the center, but instead a dot or hash, then your head position must change every so slightly especially closer towards the picket. Everyone knows to maintain consistent cheekweld, but this can slip if using dotz. In theory, I think one could still maintain consistent alignment and keep the crosshair intersection the 'center' and place the dot with peripheral vision, but I don't think this happens. The dot becomes the new center and the center changes with every distance. And for evaluation, you need the target to be at the actual distances in order to see how things work.

If using holdover with a 6x Leupo or 6x FF, there's generally little parallax, but even on some 9x scopes there can be considerable. And we've seen the reticle focus have a big affect on perceived parallax on some scopes. One day someone will shoot really well at 200, 300, 400, and 500 but on another day they'll be really low at say 300 yards. The difference was the reticle focus and increased parallax. Those fast focus scopes now have witness marks for reticle focus, or are fixed in position so that it can't change. Scopes with jam nuts are obviously immune to change for the most part, but it's still important to check parallax at actual shooting distance and not just reticle image when setting the focus. None of the dotz-equipped scopes have side-focus or AO.

Parallax could still be a problem using a turret, but you're concentrating on the center for elevation and sliding wind so you're still closer to the center than when using holdover and sliding wind. And in many conditions, the value to slide for wind is small compared to what's need for holdover. I've got all my MQ scopes dialed for parallax. The 6x and 3-9x scopes have squat for parallax. The 10x scopes needed a witness mark on the focus rings.

Jason
 

bobnob

Well-known member
Jan 15, 2016
566
4
NSW, Australia
Jason thanks for those things to take away and consider.

For my style of hunting, I like to keep a point blank range if about 3-4" from point of aim. That way I can aim dead centre on a pig's shoulder and know at worst, I'll have a high or low shoulder shot.

With a 230y zero and this load I've got a PBR of +- 3" to 275y. From 275 to 340, the low circle intersection does the same thing for me.

Beyond that, there gets to be a few "gaps" in the 3" PBR, unless the beast is ranged within a range bracket near to the zero on the dot or the duplex junction,; I'll be guessing holdovers on BDC aiming points. Not pretty with my maths!

350y is about as far as I have business shooting a pig, goat or deer anyway from field rests. The crosshair itself and the circle will accommodate that.

The dot and duplex junction will serve some purpose I am sure, especially with more practice. Nice to be able to line up steel at 500y for fun, and have certainty your dope is right.

I'll do some shooting to test out the parallax issues you've discussed.

Once I save up enough milk bottle-tops I'll plonk a 6x MQ or MOA on there and just use the reticle I imagine. That may open some doors...

Thanks

Bob
 

Big Stick

Well-known member
Nov 18, 2007
42,710
482
Paradise
A good zero is key.

Been LOTSA 6x MQ's sold here at work lately,as well as a purty good run on the Sig LRF's.............(grin)
 

bobnob

Well-known member
Jan 15, 2016
566
4
NSW, Australia
I had the nagging feeling I hadn't quite got the above subtension check right. I only shot the reticle at 125y, and I was using sh!t Core Lokt left over reloads.

Took the long target out to 260y...



And shot 3 shot groups with my 168g Amax load. Point of aim was the red diamond at bottom (not the black one below it)...



Faint R-L breeze came and went.

So on 12x the sub tensions ended up as follows...

Bottom of circle - 2.4moa
Dot. - 5moa
Duplex crosshair junction - 8.75moa

Just thought I'd correct the data for anyone that had any interest in this scope.
 

Big Stick

Well-known member
Nov 18, 2007
42,710
482
Paradise
Gonna practice my through Spotter Videography in today's wind,to drag along to work and connect a few dots....................
 

bobnob

Well-known member
Jan 15, 2016
566
4
NSW, Australia
By the way just when you thought I couldn't disgust you more with my choices of optics, I've been wringing out a Sightron S1 SIH TAC with mil-dots the last few weeks.

Not the worst for a cheapie, though I'd be reluctant to put it on anything that rattles it too much.

Made in PI believe.
 

Big Stick

Well-known member
Nov 18, 2007
42,710
482
Paradise
I got the video shit down ROCK solid today. Dabbled both Manfrotto and Giotto's legs today and settled on the shorter Manfrotto,due it's increase in stability.

Gonna be some fucking EPIC kill footage,for certain...................
 

Big Stick

Well-known member
Nov 18, 2007
42,710
482
Paradise
Spent last evening lettin' folks subtend wind and dabble in Playgrounds greater than they had prior.

Pretty fun shit.

Pass the MQ....................(grin)