Home Forums Hunting & Shooting Custom Rifles & Wildcats Turrets 101....................

I've been bombed with Emails,PM's and phone calls from guys that are goin' turret crazy all of the sudden. As my typed words are of even less use than my verbal communications,I thought it prudent to Post a coupla pictures that might help those that I managed to confuse.

I just hope my text doesn't muddle the pictures!



OK,in this picture is a Leupold "regular" turret. The type that wears a cover if you should want it and I generally do. So this is the way your rifle sets after you have it on paper at your preferred "normal'' zero range. On this particular rifle I like it sighted in and zeroed at 250yds. The bullet must strike +2.3" high at 100yds to yield that desired result. After that confirmation,I loosen up the three hex head screws that affix the micrometer head to the internal elevation spindle. I align the "0" reference number,with the vertical index indicator at the base of the turret assembly and retighten the set screws.

So in this configuration,I have a "regular" rifle sighted in a regular manner,the turret is just a bump on top of the scope and from my muzzle to the 250yd line I needn't give it a thought.

Savvy?



OK,now here is the turret moved in the upwards direction and it will shift impact from my pre-established zero. It is at the 3MOA setting,which is 12 seperate .25MOA graduations from my zeroed starting point. The U- indicator at the top tells me that counter clockwise increases elevation and the opposite reduces it.

With just that subtle amount of elevation increase,my rifle's zero has now changed from the 250yd line,to the 375yd line. So at that predetermined distance(as this ain't a guessin' game),I can paste my crosshairs dead on the target and that is where that bullet will impact.

After the shot,I return the scope to "0" and I'm back to my predetermined 250yd preference.



In this picture,the crosshairs have moved even farther upwards in elevation travel. The reflection from the flash obscures the whole minute designation mark,but this is a 7.5MOA poke. That is 7 whole minutes and two .25 "clicks".

The micrometer head is marked well and easily read. It starts at "0" goes to "3","6","9","12" and 15 ='s a complete revolution back to "0". Between those numbers are hash lines,designating the whole minute values(the longest of the hash marks). The mid lengthed hash marks are .50MOA designators and the tiny ones are .25MOA graduations. With about 7 seconds practice,it becomes very easy to cypher(even for me).

So with 7.5MOA up in the glass,this rifle is now dead on at the 525yd line. I make that shot,return the glass back down to "0" and I'm back to my favorite 250yd zero for this particular rifle.

Now to find the info to feed your scope,you gotta know a coupla things. The bullet's speed,BC,sight height and atmosphere. That will yield a trajectory drop chart that will likely yield an amazingly close ballistic profile.

From there,one must ascertain that generated data and the rifle/scope combo are in perfect harmony. That is yielded by shooting at a known(confirmed) distance and comparing generated findings to actual findings and fine tuning the data. All very easy.

This game is won and lost with range determination and an accurate/repeateable scope(they call 'em Leupolds). The laser is the measuring device and the 1200LRF Leica is THE machine for po' folks like me.



So here is a trajectory data reference chart,as spewed from my PACT Ballistic Computer.

I sorta screwed up,as this printout is not in sync with the above trajectory curve,though the principles are precisely the same. This is for a different rifle and I'm guessin' you know which one,from the El Marko credits atop the ribbon.

Anyhow,we'll use this for reference and at least it uses the same 250yd zero,one which I find useful for a bunch of different chamberings.

So let's say we've done the 100yd thing(sighted +2.0") at that distance and we've confirmed that we are on the money at the 250yd line. We now loosen the set screws an index the turret's head,to correspond with our "0" designation.

No we wanna see EXACTLY what it takes to get further downrange. To start,you divide the trajectory drop in inches,by the distance of the shot which is in yards.

So let's jump right to 450yds as a curiousity. To find the MOA info you need to feed the scope,you divide the drop (20") by range in yds and I designate yardage in decimal configuration. A 50 yard shot is divided by .50. A 125 yard shot is divided by 1.25. a 500 yard shot is 5.00. An 875 yard shot is 8.75. That decimal will yield a factor that we can use to round up to the nearest .25MOA "click" adjustment in the scope. Savvy?

Soooooo...20" divided by 4.50 yields 4.44MOA. Well we haven't the graduations required to dial that elevation in as the scope is graduated in 1/4MOA "clicks". BUT,we can round to 4.50MOA. that is 4 whole numbers and 2 "clicks" of .25 per each.

Now as a curiousity,let's see how much precision we "lost" by rounding up to the nearest 1/4MOA graduation our scope allows us. Simply multiply 4.50(range in yards) x 4.50MOA(our nearest rounded adjustment graduation) ='s 20.25". The correction we dialed deviated but 1/4" from perfection,in a perfect world.

A 1/4" "click" at 100yds shifts impact 1/4". That adjustment at 200yds,shifts impact by 1/2". At 1000yds that 1/4" "click" is now moving impact 2-1/2" per "click". Savvy?

Some would think that because it is a 1/4" "click" scope,you'd have the graduations to negate that 1/4" difference between the actual 20" drop chart figure and the 20.25" correction we rounded up to,but the ''clicks" grow in size as range is extended. That is why I like toss that decimal in there and round to the nearest .25MOA graduation,because that is the finest adjustment I can mechanically make at ANY distance.

Soooooo....let's crack somethin' at 850yds. That is the drop in inches (152.1") divided by 8.50 and that yields 17.89MOA. My preference is to round up and the next 1/4 minute graduation mechanically available is at 18MOA. So that is one complete turret upward revolution(15MOA per revolution) and 3 more whole minutes. Whammo,make the shot,crank down to zero and you are back at 250yds.

See howww easy it is?.........................

Stick,

Post a pic of the "Cheat Sheet" that is taped on the stock that shows MOA values at the various ranges or someone will think you need a pocket calculator and ballistic printout to figure how much "up" to click in.

I discussed a drop chart but didn't illustrate it. There are lotsa deviations on the theme,but this is how I like mine oriented.



My preference is to have them on the port side of the buttstock and running perpendicular to the stock. That way it is easy to glance at from any position and confirm a reading. I generally use a 10MPH wind factor,to keep abreast of that situation. If it's blowing 25mph it's easy to multiply by 2.5 to get the 25mph value.

Reading and doping the wind is more MOJO and Black Magic than Physics......................

Good post Stick. You explained yourself rather well! I don't especially like the looks of a tall turret on top of my scope but I can sure see it's benefits. I'll have to ponder some on this.

HogWild

The Cheat Sheet/Drop Chart illustration ties it all together and makes/made perfect sense to me.

Laser a buck @ 400yds- glance at stock- go up 4 MOA-paste crosshairs dead center-squeeze trigger-punch tag...

Makes sense to me.

That was well done and solves another head scratching, befuddlement of mine. Much appreciated. I have been curious though I used reticle bracketing and hold over. Maybe one day, if you ever buy another Ruger 77 MK II, you might, also, discuss how to stone the trigger and post photos for those of us who are mechanically challenged. Then again, there could be liability ramifications with that so I would understand. Do you use the Heavy Duplex or 4A? I assume you do not because of the distances that you shoot.

Awesome stuff. Thanks for posting it.

My main problem here is that the ONLY range within 1.5 hours driving time only goes to 200 yds. so I can't perform the actual verification.

Can you clarify one point? Do you prefer to send a scope back to Leupold for installation as opposed to Premier?

Thanks.

I touched on it upon another Thread(forget which one),but my preference is for Leupold to do my work. That because they are both the Manufacturer and are a repair facility,which Premiere is not. That's not cussing Premiere,but I like to have the scopes innards checked while it is in the "shop".

Leupold does that(gratis) and will install the turret all within a very short timeframe. The turret is $53.

I'm very happy with a standard duplex reticle in all applications..............

Thanks Stick, appreciate it.

Stick

Many thanks!

Delbert

Big Stick,
Newbie here. Very first post, gotta start somewhere. I have been using the same system as you for just over a year and it seems to work very well. There will always be some changes in the very upper end of the chart with temp/press etc but for the most part it is very reliable. When I get my drop chart just the way I want it, a best fit average from real world groups, I am thinking of purchasing one of these little jewels:

Kenton Industries Tuned Trajectory Compensator

I am not quite settled for a drop chart as I haven't made a final decision between 3 fairly good loads.

Shummy

Shummy,

I see alotta guys like the Kenton,especially on the M3's.

There is another doohickey that resembles another turret that has a drop chart you can pull out of it,sorta like a tape measure. You can mark your dope upon it and affix the assembly upon your scope's tube. You've likely seen it,though the manufacturer escapes the tip of my tongue this very second.

I like the stock deal,as that is what I am accustomed to and it is easy to swap out,should the mood strike. As long as a guy has good dope secured in some fashion,he is in very good shape. Preferences will vary,but the end result will largely be the same..............

The only turreted rifle I've shot was Flinch's 25-284. I really like the way he handled it. He wrapped the top portion of the elevation turret with masking tape and drew lines corresponding to different distances. That way you lazer the yardage, turn the turret to that number and BANG. Seemed pretty slick. BTW, the lines were oriented so that they meshed with the marks on the turret. I guess this is another option to a 'cheat sheet'. <img src="/ubbthreads/images/graemlins/wink.gif" alt="" />

Thanks Pointer, I hadn't thought of that.
I find two more handy things about turrets. One, they make rezeroing for a shorter range nice too. Why do that ? To eliminate that plus 2-3 inches for a precise shot, like a small critter, or hole in cover. Two, they are handy for switching ammo.
I don't have the windage turret installed on my hunting rifles. Long Range hunting/target rifles yes. But I find the single elevation turret is sufficent for anything I'll do under say 500-600 yds. E

Hey, Flinch must of added that to his scope since I last shot them. I like that idea. I've used Big Stick's cheat sheet method as well, but I had the advantage of him coaching me at the time, it was bad news for the bear. Let's just say those turrets really work and I'm a confirmed believer. Now what I really want to know is how Big Stick got those custom "rust" blued rings? Izzat part of the camoflague scheme? Looks like a real art and science <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />

You mock my Custom SE thread locking compound? The nerve!

I even steelwooled the bastards a smidge before I took the pics and said ''hell with it" and admitted defeat.

Bad part is that's one of my "purty" ones(Lilja heavy barreled A2 in 7-08). 'Tis the price of playing in this park...............

Does the rust cost extra?

WB.

Everybody interested a little tip I like to use when just shooting for fun(not doping the wind, humidity, elevation....ect.). After establishing you rifle's zero at 100 yards, take a plain white sticky back label and wrap it around the turret and cover all those marks. Make a mark on the label at the vertical center line and above it write the #1, with a fine line marker. Next, zero you rifle at 150 yards and at the same vertical line on the turret make a mark and above it write #1.5. Continue to do this as far as you care to shoot. Then cover the label with a strip of clear packaging tape to make it water resistant. The next time you are out shooting and see a target at 350 yards spin the elevation to #3.5 and dope the wind and send a bullet down range. This tip has worked very well for me in the past. This is the same type of system I used on my Leupold Mark 4 M3, except that the turrets came from Leupold already marked for the round I was shooting.



***If anyone from Leupold is listening I wish you would make the turrets without any markings available for aftermarket purchas and I would make the marks myself.***(personal rant)

One other tip is for you range card. Take you holdovers/holdoffs and using double stick carpet tape stick it to the inside of you flip-up scope caps and cover it with clear packaging tape. Using the computer I shrink or inlarge the chart to fit inside the caps. You can not read it that close with you head on the stock but lifting you head back a little works for me.

These are just a guess since I don't have them handy right now.
Mine look something like this. 100 yards/10mph crosswind/20 mph crosswind.
You can substitute the number of clicks for windage instead of MOA as I have used.

100/0.5/1.0
150/1.5/3.0
200/3.5/7.0
250/7.0/14
and so on

For my hunting rifle, without turrets, I zero the rifle for my Max. point blank range and insert bullet drop in the chart instead of the 10 mph holdoff, and move the 10mph windage in place of the 20mph..
Just a tip for those interested

Darkside

Sky, I admit the "tactical tape" is a new thing on the scope. I get excited and can't count MOA's worth a crap when a critter is in the scope. Two years ago I turned the turret the wrong way and shot a buck in the leg at 400 yards. I now have masking tape with hash marks marked with the yardage above them. No more misses for me <img src="/ubbthreads/images/graemlins/wink.gif" alt="" /> .

One more very quick and easy way to set up your turrets is to find a rock, target or other stationary (small) object and range it to the nearest whole number, ie. 300 yards, 400 yards, 500 yards etc. Do this after initial 200 or 250 yard zero. Shoot and walk the bullet to the target at 300 yards and make a note of the # of clicks or MOA to consistently hit the target at that range. Next, find a target at 400 yards and repeat. You get the idea. For me, this method shortens the guessing that takes place on computer ballistic programs, B.C.s, velocities, etc. You don't even need a chronograph or ballistic program to perform this. You set your scope for your current load and run with it. You will need a spotter to call your shots accurately though and a good rest. Then write your cheat sheet on your scope or stock. Mine use to look like the one below before I put the masking tape on my dial.

200 yards 0 clicks (zero)
300 yards 7 clicks (2.25 MOA)
400 yards 14 clicks (3.50 MOA)
500 yards 21 clicks (5.25 MOA)
600 yards 33 clicks (8.25 MOA) etc.

The neat thing with the above sheet is that it works exactly for my 7mm loads, .25-284 loads and my .22-250 loads. My .30-06 shoots slower, so I have a separate sheet for it. Flinch

Awesome post guys. Clears up a lot and 'splains it in little words guys like me can understand. Saving, printing, saving again, putting in the safe...
SD