Awhile back I had a huge epiphany. First, let me ensure this is appropriate for the Appleseed folks.
Questions, do you shoot KD? Have you not qualified yet?
Do you struggle with scores in slow prone or rapid prone? How about rapid seated?
And lastly....Are you using a Scope?
If it is yes to the last question, this message is FOR YOU!
When the NRA and CMP opted to change the rules for High Power Service Rifle Competition and allow optics (no greater than 4.5X), it really changed the sport significantly a couple years ago.
High Masters (those scoring better than 97% on a regular basis.....awesome shooters) made the switch. But when they made the switch from irons to optics, many things had to be considered. I'll not get into these details now (more at a later date), but I will elaborate on the what I call the MAGIC GOLDEN Scope Device.
Any error on iron sights in sight alignment is a HUGE DEAL on the target. What about scopes? Those reticles are already aligned right? So why concern ourselves with that.
With the irons....sight alignment...correction, PROPER SIGHT ALIGNMENT is achieved by a CONSISTENT and REPEATABLE cheek weld. Sight Alignment is pretty much automatic with a consistent and repeatable cheek weld.
Now look at that scope ocular (eyepiece). Compare the size of that to the size of that iron sight rear peep! LOTS bigger right?
NOW comes the ERROR.....that HUGE ocular (when compared to a rear peep), can and does and will for most breed INCONSISTENT cheek weld. Inconsistent cheek weld is not good for results on the target. It can change an X into a 9 or 8.
So....those High Masters, recognizing this, did some experimentation. There are basically 2 things they came up with.
One is a Butler Creek Scope Cap for the Objective (front piece). There is a 1/8" - 1/4" centered hole drilled in the cap. We shoot with the cap closed. Without proper and repeatable cheek weld, you will not be able to see the target. It works VERY Well. It robs some light, but not enough to concern me. I shot with mine on in very dim/dark/rainy conditions under a dark firing line. No problems shooting a 197-13X on the MR-52 target (600 yard reduced target for 200 yards).
The other is an Ocular Disc. This is a piece of plexiglass with a centered hole. Clear or Tinted glass is up to you.
I have used both. The rear disc acts like a peep on a rear sight. It will show you any slight errors in cheek weld/position and is worth many points to me on target.
SO....last year I used the front cover in HP. Halfway thru the season I removed it, thinking it was robbing light. I was a 97% average 600 yard prone shooter before removing the cover. When I removed it, my next 2 matches were also 97% average....but slowly over the next 13 matches....I started to drop points. I never equated that to the cover or more importantly to my cheek weld becoming inconsistent. I ended the second half of the season at 95% slow prone average.
Put both the rear and front covers on for a match the beginning of this year and was at a 97% average again.
I keep detailed data and I know this works.
It will work well for AS as well. For a new upcoming 3 position shooter, it will at a minimum enforce a good repeatable cheek weld. If you are already struggling with the positions, it may be frustrating to get a sight picture at first. But this will help you if you use it.
Many of those High Masters have since removed the covers, as they have developed the muscle memory for the position to ensure a good cheek weld. I am not a High Master, and the rifle I shoot (SVC rifle) does not allow the cheek piece to be raised or the stock adjusted for cant. I will continue to use the scope covers until I move up to a "match rifle".
Give it a shot, it really does work.
You can make your own front cover, just make sure that hole is centered. White Oak Armament makes the rear discs for a few scopes. Also Holub Machine and Repair (www.newhighpower.com) makes the rear covers.
Ray Vin (google them) makes Delrin slip on front covers.
I posted this a year or so ago, in Rimfire Central. Since then, I have continued to use only the rear cover with the clear plexiglass. I no longer use the front cover. I also witnessed an Army Marksmanship Unit competitor this past week at the CMP New England Games using a rear cover on his Night Force scope. I guess it all comes down to "What works for you".
As stated above, many high masters have removed the covers, but....many still continue to use either the rear, front or both. For many, it just reinforces a consistent cheek weld.
This is NOT about parralax, however, it will help immensely with that as well. Take a Vortex PST 1-4, I believe that is parralax free at 200 yards, but at 600 yards it can induce some parralax error (absolutely not enough to throw one 1-2 MOA out of the X ring). Regardless, the tiny hole in the cover will alleviate any concern about parralax error as well.
Any Butler Creek style cap can be modified to use with the hole. Give it a try, you may see a significant reduction in group sizes. I have not tried this at 25M on the rimfire AQT yet, but at some point I do intend to see what it will yield me. It will definitely help at distances greater than 100 yards.
Couple Pics of what the rear disc on my March scope looks like....look for the dark circle resembling a rear peep. Ensuring that circle appears perfect before shot execution is where the magic happens!
R/
Chris
This is great stuff! I have been trying to work on more consistent cheek weld / pressure but these scope mods should really make that task easier and more obvious.
Thanks!!
Absolutely correct! I got a Ray Vin front aperture after seeing a post you had made years ago. It definitely helps shoot tighter groups.
Been struggling to find a clear rear one but maybe one of your links has it now. Burris MTAC isn't exactly an ideal High Power scope so probably not the first model they make them for.
Here's what it's helped me do at 685 yards slung up just like we teach.
(https://www.ar15.com/media/mediaFiles/84345/target_3_700_yards_12_Nov_for_forum-388544.JPG)
Very respectable group Lomshek!!
I suppose one could make their own rear disc. Plexiglass, and electrical tape. We have electrical tape on my Daughters Vortex as the one Dave Holub sells is slip fit. Contact Dave, he may be able to make you one....or try making your own.
R/
Chris
Quote from: Lomshek on September 28, 2019, 05:19:47 PM
Absolutely correct! I got a Ray Vin front aperture after seeing a post you had made years ago. It definitely helps shoot tighter groups.
Been struggling to find a clear rear one but maybe one of your links has it now. Burris MTAC isn't exactly an ideal High Power scope so probably not the first model they make them for.
Here's what it's helped me do at 685 yards slung up just like we teach.
(https://www.ar15.com/media/mediaFiles/84345/target_3_700_yards_12_Nov_for_forum-388544.JPG)
Quote from: Lomshek on September 28, 2019, 05:19:47 PM
Been struggling to find a clear rear one but maybe one of your links has it now. Burris MTAC isn't exactly an ideal High Power scope so probably not the first model they make them for.
I've been using a clear one from White Oak for highpower this season, on an Athlon service rifle optic. I like that combination quite a bit.
https://www.whiteoakarmament.com/catalogsearch/result/?q=reducer (https://www.whiteoakarmament.com/catalogsearch/result/?q=reducer)
Nice group at that distance!
Quote from: USNAVYCHIEF(Ret) on September 28, 2019, 05:27:08 PM
Very respectable group Lomshek!!
I suppose one could make their own rear disc. Plexiglass, and electrical tape. We have electrical tape on my Daughters Vortex as the one Dave Holub sells is slip fit. Contact Dave, he may be able to make you one....or try making your own.
R/
Chris
Thanks! Yeah I'll call and see what he can do. I'm too OCD to make my own without being able to verify it's perfectly on center. I want happy little concentric circles to the .0001!
Thanks! Yeah I'll call and see what he can do. I'm too OCD to make my own without being able to verify it's perfectly on center. I want happy little concentric circles to the .0001!
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I do not think having it perfectly centered is critical, your human eyeball is a very accurate measuring device.
What is crucial, is that once it is set....it stays put! Make damn sure it is not going to move on you.
My March scope has the White Oak device, and that screws into the Ocular. The inner ring, came loose on me during a match earlier this year, and it caused me to string shots diagonally up into the 7 Ring!
I did not realize it had shifted until I got home. It caused me a 3.5 MOA diagonal shift.
So...for the slip on/press fit ones like used on the Vortex PST....that gets wrapped on with electrical tape, and then witness marked with a sharpie.
Same with the screw in ones...., I have them in tight, and have marked the ring with a witness mark.
So far so good. But, if they shift again, at least I will know.
Another note on this....the White Oak lens....(forgive my lack of optical vocabulary)...the circle that is centered/drilled, one side is FLAT with just the circle, and the other side is concave/convex? It is flat on one side...and the other side looks like a countersunk hole.
I actually shoot with the countersunk hole facing my eye. It seems to give me a much darker and wider appearance of a rear peep, when compared to the flat side.
It is all personal preference.
What I am looking for when shooting by position:
Standing: I could care less if the rifle is canted (and it often is), and the center of the reticle is not always centered in the rear peep, this is OK.....it is a LARGE target for standing, and the error will not toss the shot out of the 10 ring. As standing hold improves, then "maybe" start to pay attention to that rear circle alignment. For me, it is a distraction when shooting standing as of now.
Rapids: I make sure it is aligned when in prep and dry fire, and when I initially drop into position, and on the magazine change. During the COF I ignore it, and it is always pretty much aligned....I pay more attention to the reticle and target hold.
Slow Prone: Here is where it shines! For every shot, I check NPA and also check the alignment of the rear circle. That is for every single shot. If I ignore it, I will not be in the 10 ring.
So....
I think a not perfectly centered hole (but one that definitely appears centered) will work, in case anyone wanted to DIY. You will likely realize a zero shift, and that is fine.
R/
Chris
I'm trying this!
Thanks