Another recent thread prompted me to conduct a basic experiment to see if there was a significant difference in speed and/or accuracy when engaging a target with an AR-15 carbine. I’ll describe the specifics of the course and weapon system in a separate post below, but in summary, I fired several timed strings of fire at a 12 inch diameter target from a distance of 50 yards to try to determine if I was faster and/or more accurate with an optical sight set to no magnification or with the power set at 3×.

Each trial without magnification or at 3× consisted of 30 separate shots timed individually.
Unsurprisingly, magnification made it significantly easier to confirm that I was on target before firing, and I had a total of three misses with no magnification and two misses with magnification.

Target engagement and firing times were a little slower with magnification.

The average of the 30 shots without magnification was 1.89 seconds to acquire and fire at the target, and with magnification the average was 1.95 seconds. The difference is obviously not very much, and even with sample sizes of 30 each, it may not be statistically significant (I’m too lazy to try to calculate it).

There are several ways an experiment like this could possibly be made more valid, but I believe it demonstrated that low magnification wasn’t a major handicap and it confirmed to me that some magnification offers a significant advantage in terms of the sight picture even at speed.

The experiment was based on firing a training course I developed several years ago.

The experiment was conducted with a Wilson Combat model “Protector S” AR-15 type carbine equipped with an SAI Optics 1-6×24mm low powered variable scope sight using Federal AE223 ammunition. The rifle and sight are reviewed here:
https://sigforum.com/eve/forum...0601935/m/3020072094

I don’t find the SAI “pointer” reticle to be quite as fast to pick up as an illuminated red dot, but it wasn’t an obvious handicap either. I usually focused my eyesight on the target and used my peripheral view of the reticle to maneuver it onto the target before shooting.




The target is an angled steel plate with an effective diameter of 12 inches and set 50 yards from the shooter. The shooter starts holding the rifle muzzle down, round chambered, safety engaged. The start signal is with a shot timer and on the signal the shooter engages the target with one shot. That constitutes one stage.

The stage standard is to hit the target within 2.5 seconds. The course consists of repeating the stage 10 times in succession. There is a 90/100% requirement to pass the course: Either the time or accuracy standard must be met at least nine times and the other (time or accuracy) standard must be met 10 times. This a difficult requirement for most shooters to meet but adds stress and pressure to the course. I usually pass a course about three-quarters or more of the time. In this experiment I passed two of three trials for each section, no magnification and magnification.

Very interesting and timely as I've been weighing optic decisions lately.

I took off a 1x Vortex prism on one of the ARs and replaced it with an EoTech. The AR pistol has an EoTech on it also. The 2nd AR rifle is wearing a 3x Vortex prism and while I like it, I don't love it. Zeroing was easy and it's been fine but I am so used to a EoTech that it's work to use the prism. Cheek weld in the same spot so I have a full field of view. I can honestly say that I'd be slow with it compared to a holographic sight and I don't mean just a hair slow either.

I have been all over the internet looking at LPVOs, red dots, ACOGs and more for a possible solution. I keep coming back to the EoTech.

I guess I know what my next rifle day will be spent doing.

This ties into the post about a do everything rifle and optic setup.

Since the shot times did not change much did the accuracy? I would like to try this test with a paper silhouette. When I shoot steel I only care if I hear a ding, a hit is a hit.

I would also like to see the shot times and accuracy comparisons at short range, maybe 5-10yrds. I would think there would be a greater shot time with magnification at closer distances.

quote:

Originally posted by gpbst3:

I would like to try this test with a paper silhouette. When I shoot steel I only care if I hear a ding, a hit is a hit.

I would also like to see the shot times and accuracy comparisons at short range, maybe 5-10yrds. I would think there would be a greater shot time with magnification at closer distances.

Paper is an excellent idea as is the 5-10 yards testing.
I'd be worried about shooting steel with 5.56 unless I was using frangible ammunition.

Using the 3x prism at close range would not be smooth IMO. I would try it just to see but I personally think I would be horrible with it.

Right now I am weighing getting an EoTech with the flip to side 3x magnifier.

The steel target I use for the course I described is the Action Target “45 Degree Static” with 4 foot stand.
https://shop.actiontarget.com/...45-degree-static.asp

Because of its slanted shape and hardness it’s safe to use with a 223 rifle at 50 yards. Ours has been hit many hundreds of times with minimal marking. The stand, however, is not hardened and does get damaged when hit with rifle bullets and even the splatter. Ours is pretty chewed up, but still has a long ways to go before it will require replacement.
Short range shooting at steel targets is not recommended. In fact, most steel target manufacturers caution against shooting them with 223 type ammunition at less than 100 yards. The 45 degree target is a specific exception because of its shape.

In general I believe that any magnification, even 1.5×, is a handicap at very short, across the room distances. I consider the rifle used for this experiment to be a “designated marksman” type setup even though the sight can be turned down to no magnification because it’s still not as good, IMO, for fastest engagements at such distances as my preferred Aimpoints.

I fired three 10-shot strings each with magnification and without. I had three misses of the 50 yard target without magnification and two with. I don’t believe, though, that anything much can be concluded from those limited sample sizes. The experimental “protocol” was also weak in other ways. For example, I had not fired that course in probably a couple of years before starting the first string of this series yesterday. That meant I was more rusty at the beginning than as I progressed. That is the sort of thing that can affect accuracy and times. At best I believe the test demonstrated that there was no obviously huge difference in my performance between magnified and not magnified sighting.

To reiterate, though, the one obvious advantage of using magnification was having a clearer sight picture. If, for example, an LE sniper had to make a shot at someone possibly wearing armor and hitting an unprotected area was essential, magnification could be critical.

Thank you for the link Sigfreund.
I know my AR500 steel target would not hold up to 5.56 rounds.

I feel magnification is a personal choice. Factors include eyesight, lighting, target size, target color, desired speed & accuracy, and firearm. For me, I shoot better for many close-ish distances with some level of magnification. I'll start with the Sigforum Postal Match thread, where we shot 3" x 5" index cards with carbines, from a high ready, with distances of 3-5-7-10-15-20-25 yards.

As our distances weren't 50 yards, things aren't entirely apples to apples. At 15 yards the cards were effectively 147% of the square inches of a 12" round at 50 yards. At 20 yards the cards were 83%. At 25 yards the 3x5 cards were 53% of the square inches of a 12" round at 50 yards.

I shot most of the Postal Match challenges with an 9mm AR with a value-line Vortex 1-4x scope. After futzing with distances and magnifications, I found that I shot best with the scope at 1x for 3-5-7 yards. I bumped the power a bit as distances increased. Probably 1.2x at 10 yards, 1.4x at 15 yards, 1.6x - 1.8x at 20 yards. At 25 yards I was generally in the 2.0x to 2.4x ballpark, depending on the lighting. I didn't keep details on performance for 1x versus higher magnifications. But I recall being at least a 1/4 second faster with the higher magnification, and I was not often cleaning the targets at 1x. I played with options after the day's official score was done.

Postal Match page 13 -- .80 seconds at 15 yards, 1.33 seconds at 20 yards, 1.47 seconds at 25 yards.

Postal March page 15, time for first hit with controlled pairs -- 1.18 seconds at 15 yards, 1.24 seconds at 20 yards, 1.79 seconds at 25 yards.

Postal Match page 15, controlled triples, but didn't save data on all times. 1.26 seconds at 25 yards, and missed once at this distance.

Postal March page 17, controlled pairs on side by side targets. I didn't save individual times, but the 20 and 25 yard first shots were likely in the 1.5 to 1.6 second ballpark.

*****
In one carbine match we often have clay pigeons as targets -- held on a wood stick, dome facing us. They're about 4 inches in diameter. Distances are generally 10-25 yards, but occasionally the match director sets one at 40-50 yards. Sometimes we're carbine only, so we can kneel for better stability. Generally we're carrying a pack with our precision rifle slung, which means leaning up against a nearby tree is our only support. The scopes I use for this match have minimum magnifications of 2x and 3.5x -- I generally fire with around 3.5x on both optics. The guys with LPVO tell me they generally shoot this target at 2-3x.

quote:

Originally posted by joatmonv:
I'd be worried about shooting steel with 5.56 unless I was using frangible ammunition.

Most of my steel is 3/8" AR500 from JC Steel. A few years ago, another AR500 provider stated that JC sources his steel from overseas -- implying that there may be some variability in quality. I have no idea, but I JC Steel works for me.

With a plate square to me, I find that the steel begins to show small surface dimples with impacts at 2600-2700 fps. With 75-77 grain bullets and a 16" barrel AR15, this occurs at around 75 yards for me. It's 100+ yards with my longer barrel AR15s. As a result, I set any of my steel closer than 200 yards.

When I decided to acquire a 300 blackout SBR, I estimated muzzle velocities for various barrel lengths. I settled on an 11" barrel, for which factory 110 grain ammo has MVs in the 2300-2400 fps ballpark. I've been as close as 10 yards to free-swinging vertical 3.8" plates and haven't dimpled the surface.

I assumed that frangible 223 ammo would solve the problem of dimpling plates. In my tests it didn't make any difference. The frangible seemed to spatter into finer pieces. But the frangible ammo generally had 55 grains bullets, which meant the MV and target impact speeds were high. I still saw steel dimples at 75 yards.

I hang targets vertically, and thus my steel is more susceptible to damage than downward-angled plates.

At least one steel target company (Action Target?) said that it’s the velocity that damages the targets and merely because a bullet is frangible doesn’t mean it won’t cause damage if driven fast enough.

The value of frangible bullets is that their fragments are less dangerous than those of conventional bullets.

I ran your drill sigfreund and thoroughly enjoyed it. My friend and I did not have a shot timer and we tried using the stopwatch on a phone but reaction times were not great starting and stopping so we just decided to run it without times.

He wanted to shoot a few of his pistols so he let me run the drill with my rifles and the AR pistol.

We measured out 50 yards on his pistol range and hung IPSC targets on his set-up.

I brought my 2 Colt 6920's and my CZ Bren 2Ms pistol. One Colt and the CZ have EoTechs on them and the other Colt has a 3x prism.

Results were what I expected and I know I was faster with the EoTech than with the 3x prism. I wasn't like seconds faster but I could tell. The thing about the prism is if you don't have the correct cheek weld, the field of view isn't whole. That's about the biggest knock on the prism. Field of view sucks.

As far as hits go, I didn't miss but then again it wasn't a steel plate. I did have a few Charlies on some runs. There was no timer but I rushed more than a few shots. If it was steel, I would have missed quite a few shots on the plate.

The EoTechs performed great for me and as a holographic sight, Field of view is excellent. Hold it 6" from your eye or 12" from your eye, it's all the same. With the zero I have on both Colts and the CZ, 50 yards was almost an inch hold under. Pretty easy to do at that range.

After I ran the drill I also shot longer range with the 2 Colts. I didn't try the AR pistol because we went out to almost 400 yards. That's not what the CZ is designed for. This is where the 3x prism shined. Not so much closer but one set of steel is at 350 yards and with the prism, it wasn't that hard. 5 shots and 4 hits. Hold over with my zero is a little over 2".

Also ran a drill with the EoTechs at 7 yards doing head shots. Basically putting the hash mark at the bottom of the ring right in the middle of a forehead. It was ALOT of fun with the AR pistol.

There is a thread in this section about the use of a 3x fixed optic. After running this drill I'm not so sure I'm going to keep the one I have. I'm seriously considering another EoTech with the flip to side 3x magnifier. I like the thought of having magnification but not all the time.

Thanks for that report.
I am always interested in how other shooters do on courses I'm familiar with.

quote:

Originally posted by sigfreund:
At least one steel target company (Action Target?) said that it’s the velocity that damages the targets and merely because a bullet is frangible doesn’t mean it won’t cause damage if driven fast enough.

The value of frangible bullets is that their fragments are less dangerous than those of conventional bullets.

A while back I did some research for my rod and gun club and found that pretty much all the companies selling AR500 steel targets recommend against 3,000 FPS ammo at the point of impact. Also, it was pretty much a universal feeling that anything steel core was going to accelerate plate wear, so you aso need to be careful with surplus Com Blok military surplus and M855 type loadings.

As to your speed and accuracy tests, the only thing I can add is I find CCO\RDS sights to be far more forgiving in terms of eye box placement than their variable counterparts. I've never used a 1-4\6\whatever optic for CQB training because I vastly prefer the simplicity of the single dot. I regularly shoot steel out to 10 yards in CQB type training, and have no problems putting the hits where I need them.