3-Gun/Multi-gun Rifle: Shooting at Longer Distances

Training Competitive Shooting
1

My first rifle I owned that I used for 3-gun sports a Leupold Vari-X II 1-4X20mm, but in the last few years I haven’t been to a match with shots past 100 and rarely did I shoot at that distance. Almost everything was 25 and less at my (then) home club, and 75 and less the other places I shot with the exception of an occasional stage with a 100 yard shot. So, I switched to red dots, which are fine even out to 150-200.

Today I shot a match with a stage that had shots at 300 and 200 yards, so I broke out the ol’ Colt with the Leupold. The thing is, I’ve never fired a shot past 240 yards, so 300 yards was completely new for me. We fired a total of 32 rounds (Virginia Count) at two IPSC metric targets, half at 300 from prone and half at 200, freestyle (I went prone). I had six total misses, but the rest were decent hits (not a lot of Ds) and about half As.

Since we didn’t score the targets in between (yeah, I know, it’s technically a violation of the rules to have that many shots per target, but no one minded), I don’t from which distance my misses occurred, nor do I know if I was high/low/left/right. My hits were pretty much spread around the paper. And since I’ve never fired a round at 300 yards, I have no idea where my rifle hits even if I have perfect sight alignment, perfect trigger press, and perfect follow-through.

I do know that at 240 yards from prone using the magazine as a monopod (as I shot today), I can shoot an entire magazine (28 rounds) into about a six inch group in about the middle of the A zone of an IPSC metric target. The gear is a Colt 16 inch HBAR with the Leupold mounted in a once piece B-Square mount. Ammo is Black Hills blue box 68gr OTM. I’m zeroed at 50 yards, which also apparently yields a second zero pretty close to 240 yards.

I held on the center of the A zone at 200, and a little high (about the top of the A zone) at 300 (estimated because 4X is not enough for me to see that kind of detail). I’m guess most of my A hits were at 200 and all of my misses were at 300.

So … obviously I need to shoot some more at 300 and beyond in order to do better, which is going to be tough since access to 300 yard ranges where I live is tough. I could run my load etc. through a ballistics computer to estimate where I need to hold with respect to elevation at 300 yards, and then confirm that estimate with some live fire when it’s possible.

But … what if my windage is off at 300 and greater, but perfect at 240 (the longest range I can shoot at my home club) and less? What would be the likely causes? A natural effect of the gyroscopic procession of the projectile? Or would it more likely be that my mount/scope isn’t perfectly aligned with the receiver/barrel? How (other than shooting at really long range) can you tell if everything is aligned properly? And if it isn’t what do you do about it?

I know I need to shoot some at 300 to figure out where I am hitting, but I’d like some thoughts to mull over for when I get to actually do that.

2

With my 20" old 3gun rifle at 300yds with a POA/POI 50yd zero the bullet would drop 5". Now with my 16" it’s more like a 6-7" drop. I use Tennessee elevation at distances beyond 250yds. Right now with the 16" and some 55gr it’ll barely make power factor. Next time I’ll be using a 18" midlength.

3

So … maybe I should hold where the upper A/B zone (i.e. head) meets the rest of the target?

I’ve never owned a 20 inch gun. Just 16 and 14.5. The gun today was a Colt 16 inch HBAR and I was shooting Black Hills 68gr OTM. I’m guessing I have a little more drop at 300 than I would if I were shooting 55gr movin’ a little faster.

4

68gr has a trajectory kinda between and AR15 and a AR10.

5

Please educate me here … I have zero experience with .308/AR-10s.

6

rhino,

      I shoot a monthly match where 80%+ of the targets are 200 - 425 yards.

      Shooting at this distance has taught me something about zero.  I use the same zero you do.  50 yards.  But embarassment has taught me to reconfirm the zero at 200 yards as well (the 50 yard zero will be point of aim / point of impact at 50 and around 220 yards for *most* 16" barrels shooting 55 grain ammo).  I use 55 grain ammo for everything from duty to competition.  I've never checked zero distances using the 68 grain stuff, but a couple guys I shoot with use 68's and the 50 yard zero.  I'll try to get you some info the next time I see one of them.

      Sometimes your point of aim / point of impact may be perfect at 50 yards and then find out your windage or elevation is off quite a bit when you run the target back to 220 yards.

      If you were holding at the top of the A zone, you shouldn't have been missing the target completely.  If memory serves me correctly, using a 50 yard zero, at 300 yards you should be 13" low (16" barrel + 55 grain ammo).

       Is the BSquare mount a flat top mount or mounted to a carry handle? 

       Is the scope mount loc-tited to the receiver (loc-tite blue #242) and have all the scope ring screws been loc-tited as well?

       If you find that the problem lies with the equipment, from my past experience, the BSquare mount is going to be the weak link.

https://www.m4carbine.net/showthread.php?t=2475

Good Luck,
Jeff

7

Thanks for the feedback, Jeff. With a 50 yard zero, what is your hold over at 425? Do you have mil-dots or something similar in your reticle?

You’re right that I shouldn’t have been missing the target completely, so I’m betting that the primary problem was trigger control and follow-through. After that, I agree that the scope mount may be a problem as well.

The one piece mount is attached to a flat top directly. The screws on rings are loc-tited, but the thumb screws that attach the mount to the picatinny rail are not. I do check them to make sure they are tight, though. Which reminds me that I need to mark them with a little paint to let me know if they have moved like I have on all of my other gear.

The mount puts the centerline of the scope at almost the same height as the iron sights, maybe 1/8 - 1/4 inch higher at the very most. I’ve confirmed the zero at 240 yards, where windage seems good and elevation is as close to “on” as I can hold with my current shooting ability.

Now that I type that again, I’m realizing that the problem is almost certainly operator error. If I’m “on” at 240, another 60 yards shouldn’t put me completely off of the paper with respect to windage (or elevation for that matter).

Thanks to you and Robb for the input (and keep it coming!).

When I get around to completing a precision rifle class, I’m hoping more of this stuff will be clear to me too.

8

I just wanted to second the idea that you need to zero at 50 and reconfirm at 200 (or 220) to make sure. At Randy Cain’s carbine class earlier this year we did exactly that and many people were surprised to find that they weren’t printing exactly where they wanted to when they got out to 200.

I don’t understand the mathematics behind it all, but if you’re planning on shooting at varied distances you’re going to want to reconfirm at 200. I would then try to get to a range that allowed me to check zeros and holdovers at distances out as far as I could envision shooting the rifle.

9

This is just numbers crunched through a ballistic calculator. Not real world tested.
 http://www.handloads.com/calc/index.html The only way to know what your rifle will really do is to chrono your load, find the ballistic coefficient, measure the center line of the scope over the centerline of the bore and run the numbers…even then it’ll be a little off, so shoot it at those distances to see what it really does.

20" AR sighted in for 50yds with 55gr Hornady FMJ traveling 3200fps.

dead on at 50yds
+1.53 high at 100yds
+1.92 high at 150yds (it peaks at 140yds)
+1.02 high at 200yds
-1.37 low at 250yds
-5.49 low at 300yds
-11.63 low at 350yds
-20.13 low at 400yds
-31.40 low at 450yds

20" AR sighted in for 50yds with 68gr Hornady traveling 2850fps.

dead on at 50yds
+1.32 high at 100yds
+1.33 high at 150yds (it peaks at 130yds)
-0.09 low at 200yds
-3.12 low at 250yds
-7.9 low at 300yds
-14.62 low at 350yds
-23.53 low at 400yds
-34.85 low at 450yds

20" AR10 sighted in for 50yds with 150gr FMJ traveling 2600fps

dead on at 50yds
+1.09 high at 100yds
+0.63 high at 150yds (peaked out at 110yds)
-1.5 low at 200yds
-5.5 low at 250yds
-11.53 low at 300yds
-19.78 low at 350yds
-30.50 low at 400yds
-43.92 low at 450yds

Same AR10 with a 35yd zero (same 150gr going 2600fps) for 3gun this would be good (makes Major PF) but at distances under 200yds you would have to hold slightly low in the A zone.

dead on at 35yds
+2.83 high at 100yds
+3.24 high at 150yds
+1.97 high at 200yds
-1.15 low at 250yds
-6.31 low at 300yds
-13.7 low at 350yds
-23.55 low at 400yds
-36.1 low at 450yds

10

Thank you!

Those numbers will give me an idea of what to expect, so it should keep me in the ballpark when I find a place to shoot past 240 yards.

Heck, the range where I shoot 240 is probably going to be lost in the next few months, so I need to find someplace else anyway.