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M@D-M@X
02-05-2010, 02:44 AM
What is a “Box Test”?
A box test is a procedure conducted to find out if a set of optics is able to track. Tracking is when the POI (point of impact) is moved in a measured & controlled manner by means of using the turrets on the optics and not altering the POA (point of aim).

Why conduct a “Box Test”?
The number one internal optics problem most shooters encounter is unreliable tracking; therefore, with any scope it is vital to test the windage and elevation adjustment on them, especially on tactical optics.


How to conduct a “Box Test”?
In order to conduct a “Box Test”, the optic been tested needs to be zeroed in at 100yds. and the rifle been used should be benched or mounted on a vise (that way you narrow down variables that might affect the test). It is also recommended that you conduct this test with very little or no wind at all and no one else shooting in your ears next to you (again, just keeping variables down). You must have a target with pre-measured and evenly spaced 1” bull’s eyes at each corner of the target. These targets are easily found and they usually include a large bulls eye in the center with 1“ apart graph lines in order to easily calculate your tracking and groupings. Try to find the targets that have at least 10” in separation between the smaller bull’s eyes in the corners the more the better (as long as it stays within the limitations of the optics).
The target is placed at 100yds. You can use the larger bull’s eye in the center to warm up on your shot placement.
To begin the “Box Test” you will need to assign one of the smaller bulls eye as your starting point (in this case we will pick the upper-right bulls eye “A”). Take 3 shots at that assigned bull’s eye and from this point you will work clockwise. In basic terms and to put it simple, you will basically direct your POI to the other 3 bull’s eyes while still maintaining your POA on the upper right bull’s eye “A”. Count the inches from the bulls eye you just shot (“A”), to that second bulls eye on the lower-right corner (“B”) (in this case we will assume this is a 10” spread).
Now, this is the tricky part. There are 2 types of measuring values used on the turrets:

The most common is the M.O.A. (minute of angle) which translates to just about 1” at 100yds or (1.0476” to be precise)
&
M.I.L. (millradian, radian, angular mil) which translate about 4” at 100yds or (3.6013869” to be precise)

Optics will have a specific value assigned to their clicks in either M.I.L. or M.O.A. I will give you 2 examples:
If you have ¼”MOA click adjustment you will need to turn your elevation turret (top of scope) down 40 clicks in order to move your POI to that second bull’s eye "B".
Or
If you have a .1MIL click adjustment you will need to turn your elevation turret (top of scope) down 28 clicks in order to move your POI to that second bull’s eye "B".

While aiming at the starting point (upper right bulls eye “A”), take 3 shots. These shots should have landed on or near the lower right bull’s eye (“B”). You will now move your POI to the bulls eye on the lower left (“C”) by turning the windage turret (right side of the scope) to the left 40 clicks (on the ¼”MOA optic) or 28 clicks (on the .1MIL optic) and then while aiming at the starting point (upper right bulls eye “A”), take 3 shots. These rounds should have impacted or landed near the lower left bull’s eye (”C”) and now you will move your POI to the upper left bull’s eye (“D”). Using your elevation turret (top of scope) turn it up 40 clicks (on the ¼”MOA optic) or 28 clicks (on the .1MIL optic) and while aiming at the starting point (upper right bulls eye “A”), take 3 shots, which should have landed on or near the upper left bulls eye (“D”).
Now for the end. Take the windage turret (right side of the scope) and turn it to the right all the back to zero or 40 clicks (on the ¼”MOA optic) or 28 clicks (on the .1MIL optic). This will move your POI back in sink with your POA, which means that your next shots should land exactly where you are aiming.

I have attached an example of a box test I conducted the day before yesterday but there were several discrepancies or as I like to call it “variables” present like 15 to 20 mile per hour gusts crosswinds and the rifle has never been fired (which takes a while for the barrel to settle in).

The rifle is a Remi 700 XCR Tactical in .308, spitting out Black Hills Gold, 168gr. Ballistic Tip Hornady A-Max @ 2650fps. The optic is a Millet TRS-1, 1/4"MOA, 4-16X50 long range, tactical scope w/illuminated green Mil-Dot reticle. As you can see below my starting point “A” actually went quite well with a sub MOA group, .47” to be exact in comparison to my practice shots (in the center). My second group on “B” it opened up a bit, about an inch but on mark. Third group on “C” was a sub MOA group but off mark to the left. Fourth group on “D” was just plain horrible, showing a flyer almost at mark with a 1.21” group and then everything fell back into place with a .53” group, aiming at what I have marked in blue.

http://i835.photobucket.com/albums/zz278/MAD-MAX-D-1/guns%20misc/RangeDay2-3-10009b.jpg


Overall, I’m very happy with the scope and the way it tracked. Considering that it is only a $300 unit and it has all the bells and whistles that other scopes have that are at 4 times its price, it did a hell of a job. The clicks are crisp, not sluggish and the glass is pretty clear but then again during the day any glass is clear. The true test of a quality glass is at low light. I really think this test would of been tighter with better conditions.


C3PO :ss1:, feel free to chime in if I missed anything. It was really late at night and I'm just working at 20% :alcoholic:

Chris
02-05-2010, 02:58 AM
good write up!

Secpro
02-05-2010, 08:57 AM
Really good write up! I looked into the Millet scopes a while back for a friend and recommend it to them. With this info it seems my recommendation was dead on.

ss1
02-05-2010, 09:38 AM
Excellent write up. I am also very happy with the millet I have on my SPR. Great value and solid clicks and accurate adjustment with their turrets. This underscores the reason why the installation of scopes should be done carefully and methodically using a leveling device and proper screw torque and locktite.

lino
02-05-2010, 09:42 AM
very nice MAX... do you have pics of the gun in the stand/vice ?

M@D-M@X
02-05-2010, 09:43 AM
Really good write up! I looked into the Millet scopes a while back for a friend and recommend it to them. With this info it seems my recommendation was dead on.

Well to tell you the truth the reason behind my box test was that this perticular TRS-1 model has given them quite some issues but I will tell you that this scope is the best bang for your buck. You can't compare this scope to a NF, Leupy or an USO but it does have something in common and it is lifetime guaranteed.

Millet an American company (made in china) got recently bought out by Bushnell so it is expected that their QC will increase. Millet's reputation rely on their DMS models which I've heard good things about.

BTW... Regarding scopes from time to time you'll get a lemon, even with the expensive 3 Gs scopes.

M@D-M@X
02-05-2010, 09:48 AM
Excellent write up. I am also very happy with the millet I have on my SPR. Great value and solid clicks and accurate adjustment with their turrets. This underscores the reason why the installation of scopes should be done carefully and methodically using a leveling device and proper screw torque and locktite.

Thanks...
As a matter of fact I was going to do a write up on bedding up a rail with JB Weld and another one installing a scope true to the rifle but sometimes I don't have the time.

M@D-M@X
02-05-2010, 09:50 AM
very nice MAX... do you have pics of the gun in the stand/vice ?

Thx lino...
Yes sir, I do.... Even video but you will need to give me some time. I'll post it on a separate post.