You’ve probably heard us talk about the “Drop Test”, either in a podcast, at a class, or in a post. If you are not sure what it is, or would like some more explanation on it, then you’ve come to the right place!

As much as we may try to treat our scopes like the delicate princesses they are, things never go perfectly when we are out in the field! Our rifles get banged up, they ride rattling around in our truck, and we might take a tumble here and there. When we finally get to the spot we love, and a great animal is right there, we need to be confident that our scope is still zeroed. Hence, the drop test! By performing the drop test on different scopes, we can evaluate the durability and ability to hold zero of a scope.

So, what are the Rokslide Scope Field Eval and Standards? 

The Evaluation:

All is conducted using rifles that have permanently bonded action to their chassis- there cannot be a shift due to the rifle/stock. Those rifles either have rails integral to the receiver, or rails permanently bonded to the receiver- there cannot be a shift due to base mounts. Any shift that is seen must come from the rings or scope itself. The rings are easy, all good picatinny rings exert a force on the rail that would physically damage the rail or scope before movement when mounted correctly- there is not a shift due to rings moving. This leaves the scope.

Full Eval:

1). Rifle is proofed with a 30-round group at 100 yards fir precision and zero. The rifles and ammunition used will be sub 1.5” for 30 rounds.

2). The proof rifle and scope go through the drop portion to prove that the rifle holds zero.

3). The new (scope being evaluated) scope is cleaned, tube degreased, rings have all oil and grease removed, scope is mounted, all screws get thread locker and torqued correctly- generally 18-20 in-lbs depending on rings.

4). Scope is mounted on rifle that was proofed and bore sighted.

5). First shot is taken at 100 yards, if on paper nine more are fired for a ten-round group. Group is checked to ensure it is within expected size- if 30 round group was 1.1”, then the ten round groups should be as well.

6). The reticle in the scope is used if it has one, or a spotter with a reticle if it doesn’t, to measure from the center of the ten-round group to the center of the aiming point. Then is adjusted.

7). A second ten round group is fired, noting of the scope adjusted exactly as it should have. Any errors are noted.

8). The target is sized based on the 30-round group. If those ten rounds all hit inside that target, then it moves on. If not, more groups are fired until it is zeroed correctly.

9). Drop evaluation. A correctly sized target is placed. On soft ground- standard grass range- a half inch padded shooting mat is placed down. The rifle is dropped once on each side (left, right, top) from 18 inches with a confirmation shot taken after each drop. Any shot that misses the sized target is noted. If it loses zero- that is a shot does not hit the sized target, then it is immediately shot on another target to check if the drop bound up the erector and if the recoil from the next round settled. If it does or does not, it is noted. Then the exact same procedure is conducted at 36 inches. Any errors noted. Then the scope/rifle is dropped three times on each side from 36”, for a total of nine drops for this portion and zero is checked. The total amount of drops from both 18” and 36” is fifteen (15).

If the scope loses zero, then the whole drop eval is repeated. If it loses zero again, then the proof scope is remounted, zeroed, and drop checked to ensure the rifle isn’t at fault. When the rifle and proof scope are proven again, the test scope is remounted, rezeroed and the drop eval repeated. If it fails the third time, it is noted and no further drop evals are conducted. Depending on use, either the scope is deemed a failure and removed from evaluation, or if still semi functional is zeroed and used for normal purposes noting when issues arrive.

10). A separate target sized correctly is used to check return to zero (RTZ). A shot is taken at the target, the elevation and windage turrets are spun for 200 mills back and forth then returned to zero. A second shot is taken, the turrets are spun 200 mils. This continues for ten times, with a total of 2,000+ mils being adjusted. The group is checked for placemat- all in the target, and size compared to baseline.

11). Live fire check of “tracking”. Two correctly sized targets are placed ten mils apart, vertically aligned. The dots are measured with the reticle as well if present. All shots will be fired aiming at the bottom target. Reticle plum is maintained throughout. A shot is fired, then the elevation is adjusted to 10 mils, second shot is fired, down 10 mils, fired, etc, etc. until ten rounds have been fired on each dot. Both groups are checked for size and placement. Any errors noted.

12). If a scope passes the initial eval, then it is mounted to standard on a proofed rifle system, is zeroed, and then carried, hunted, and shot for 3,000 rounds.

Scopes are labeled either “PASS”, “PARTIAL FAIL”, or “FAIL”.

What does that mean exactly-

PASS: In initial eval the scope adjusted and tracked within 2%, and returned to zero correctly. All groups were sized as they should, no off-call shots. All rounds from the drop test hit the group sized target- no loss of zero at all. Scope was used heavily for the 3,000 rounds without issue.

PARTIAL FAIL: In initial evaluation either the scope has more than 2% error in adjustments but was consistent, groups sizes were larger than base line, or the scope passed the 18” and 36” single drops holding zero but lost zero on the 3×3 36” drops.
FAIL: In initial evaluation the scope failed to function as an aiming device. Tracking or adjustments were more than 10% off or not consistent, it did not return to zero or failed to maintain zero on the single 18” or 36” drops.