Today I helped a new member qualify at long range at our club. When we qualify someone for long range, that means they get the combination to the long range gate and they can go practice there unsupervised. If you have an NRA LR rating, you are automatically qualified, but comparatively few people have the NRA rating because they are just starting out at LR.
The qualification process is not complicated, we just want to see that the shooter has a rifle that can be on target at 600 and then 1000 yards and that the shooter has the skills to stay on target.
Today was a work day at the range and one we finished the work, we had one new member who wanted to get LRQ. I stayed behind with a couple other people to go through the process.
The shooter had a 6.5 PRC rifle, the first time I've seen that caliber and he was using Hornady factory Match ammo, 147gr ELD cartridges.
We loaded up a target with an LR-1FC face and then we were on the 600 yard line and told him to go ahead and do his thing. He put in his calculated come ups and then proceeded to fire 5 rounds. The conditions were absolutely perfect and his first shot at 600yards was an X and then he shot, 4, x, x, x. and that was all we needed. Very well done, even if the target was a 1000 yard target. So we went back to the 1000 yard line.
His first shot was an 8 at 10 o'clock. The next was an 8 at 6 o'clock. The third shot did not get to the target line, we think it fell short in the berm as the puller heard nothing. The next shot was also short, never detected.
So at that point I told him to hold top of the target, hoping he would at least clear the berm. The puller reported the bullet went ABOVE the target. Whiskey Tango Foxtrot. We then told him to aim top of the black, the next shot was not detected, did not get into the target area. Again back to the top of the target; the next shot was detected as top of the black. This was totally crazy.
Then one person reminded us this was Factory Ammo he was using. The light came on and we let him shoot a few more rounds and it was just crazy. Where he had been superb at 600 yards, it was total junk at 1000 yards.
I told him that stuff happens past 600 yards and that he definitely had the skills and the rifle for it, but his ammo was crap. Hornady Match, pfffft.
That's why we handload match ammo.
I have not yet shot a 6.5PRC, but I have spoken to a handful of guys who have them. From my over-simplified view, its ballistics are similar to a 6.5 SAUM. Compared to a 6.5 Creedmoor, it pushes a much better bullet at 200-ish fps faster. Evidently it is quite accurate, and it holds vertical to a long ways out there.
Starting with my 6.5CM -- the 140ELD bullet flies quite well to at least a mile. My rifle holds vertical well to that distance, even though the bullet is right around mach 1.0 at thinner air. The bullet is flying nose first and does not produce keyhole impacts. I have shot a few boxes of 6.5CM 147ELD loads out to 800 yards, and they flew at least as well as the 140ELD. Guys who have shot the 6.5PRC with factory loads at a mile stated they flew well.
Something is seriously wrong if the PRC is wonky at 1,000 yards. Hornady is not above making bad ammo, but bad for them is an odd flyer that's 1 or 2 MOA from the norm. I suspect there are other issues that must be verified, too -- rifle, shooter, optics.....
|One Who Knows|
I suspect the scope.
Hey fritz, thanks for the informative reply. It's exactly the information I wanted to get.
I spent some time this weekend reading up on the 6.5 PRC and it reminded me a lot of the 6.5-284 the F-openers used to revere until they fell into the 7mm rabbit hole.
The situation this weekend was out of the ordinary. I was not aware that we were going to LRQ a new member and the only thing I had brought with me was my shooting bag with my earmuffs, and various what I call "person things." Items to take care of the shooter not the equipment. So I only had a pair of small binoculars (7x) and a monocular (8x). Not proper equipment to try to read trace.
At any rate, after his first shot at 600 came up an X and the next one was a 10 just to the left of it and then he followed up with 3 more Xs, I felt pretty confident that 1000 yards was going to be a cake walk. The conditions were superb and all I expected was bit of spindrift that may need correction at 1000, maybe a half MOA, if that.
So when his first shot was an 8 at 10 o'clock, I thought we were ok. Then the next shot was nicely centered but straight down.
On the target that was about 2MOA (20 inches) of displacement. Then the next two shots fell short, that would be another 3 MOA minimum straight down. And then have him go over the target as he was aiming at the top of the target, that would represent about 10MOA of variation.
I was seeing variations that made no sense, especially after the shooter had done so well at 600 yards. The scope used was a Nightforce of some kind, and it looked like a new model. It was mounted properly and the shooter was obviously very competent. The other "seasoned" shooters who were present immediately latched on to "factory ammo," and I was hesitant to say the equipment was broken somehow. I have difficulty getting my mind around the fact something went tango uniform on the rifle between 600 and 1000 yards. The guy started at 100 that morning and he brought us a 100 yard target that was spectacular. Then he shot brilliantly at 600 yards from the first shot. And now everything broke at 1000 yards?
The devil really does live beyond 600 yards.
At any rate, he ran out of ammo after 5-6 shots at 1000 and that's as far as we got. If the scope really did go bad right at that moment, it's the biggest stroke of bad luck I've seen in a few weeks. I kept my eye on the shooter while he was going through the motions and I did not detect anything out of place in the gun handling.
Go figure. I'll update here is something develops.
I have a little more info now on the 147 ELD bullet, both from personal shooting with 6.5 Creedmoor 147 factory ammo, and from a squad mate who has shot the 6.5 PRC factory 147 ammo.
In short, Hornady's published BC is overstated for the bullet. I used JBM ballistics and the other guy used a similar type ballistics program. He said that in order to true up flight with the 147, he had to decrease the published G7 by about .020. If one uses the G1 numbers, they may be overstated by about .040.
I shot in the Raton magnum match this morning at the Whittington center. We had 8 targets from 875 to 2023 yards. I brought both 140 and 147 ELD ammo, with the hope of comparing which one worked better for long distance.
JBM predicts my 140 ELD-M flight really well out to maybe 1500 yards, and sort-of well out to 1700 yards. In reality, the load is no longer competitive at 1300-1400-ish yards. I hit no targets further than 1600, with the majority of my hits at 875, 1125, and 1319 yards. We had fairly small targets -- generally about 1.5 MOA is size. Winds were mostly reasonable, 4-9 MPH, but with subtle changes.
Based on MV and JBM, the 147 ELD was right on at 875 yards. Yeehaw. But it took quite a bit of seat of the pants adjustments to obtain elevation on the longer targets. Impacts were definitely low at 1125 and 1319 yards. Due to the lack of bare dirt around these targets, I couldn't get an accurate elevation reading. At 1462 yards JBM predicted 46 MOA of elevation (100 yard zero, 7k DA), but I needed 49 MOA. At 1606 yards JBM predicted 53.5 MOA of elevation, but I needed 57 MOA. I didn't try any further out.
The guy shooting next to me with the 6.5 PRC ixnayed the 147 ELD bullets, and now loads SMK 150. He shot quite well with the SMK loads (MV of about 3100 fps), and found that his ballistic program provided flawless elevation data using the published SMK BC.
Thanks for the great follow up information, fritz. I've had a busy few weeks with TSRA last week and running a match this week. I have not seen or heard from the shooter in the last few weeks, I was hoping to see him in these last few events, but he did not show up. I'll update as things develop, if they ever do.
|Retired, laying back |
and enjoying life
Nowhere in your guys class at long range shooting but I do use Nightforce scopes on prairie dogs at ranges out to 1200 yards. One thing I have learned with NF is not all reticles are easy to get consistent hits at all ranges. I've had some that I could slaughtered dogs out to 500-600 yards all day long but couldn't consistently hit a bull in the ass at longer ranges. I hand load all my own bullets so this perplexed me for a long time. I have gone through a lot of their options finding something that works for me. Might want to look at the glass and see which reticle he had and how much experience with it, as that could have been a big part of the problem. And yes the devil definitely lives out past the 600 yard line.This message has been edited. Last edited by: low8option,
Freedom comes from the will of man. In America it is guaranteed by the 2nd Amendment
It's tough to say what's causing your issues, but I suspect it's related to bullet ballistics instead of scope tracking.
I have multiple NF scopes, all with some form of MOA reticles and turrets. Models include NXS 5.5-22x, NXS F1 3.5-15x, NXS Compact 2.5-10x, SHV F1 4-14x, ATACR F1 4-16x, ATACR F1 5-25x, and ATACR F1 7-35x. All scopes have proven accurate elevation tracking of at least 50 MOA, and I've pushed some to 70 MOA. Tracking was confirmed by bullet ballistics and tall target tests.
Some of the distances I've pushed loads to:
- 750 yards with Hornady 55 VMax. Tracking and bullet performance were good.
- 800 yards with Hornady 75 HPBT. Tracking and bullet performance were good.
- 800 yards with Hornady 73 ELD-M. Tracking and bullet performance were good.
- 800 yards with SMK 69. Tracking and bullet performance were good. Vertical variation became noticeably greater at 900 yards. At 1000 yards the bullets were tumbling, with vertical POI variations measured in yards.
- 1000 yards with FGMM 168 at high altitude. Tracking and bullet performance were good.
- 1200 yards with FGMM 175 at high altitude. Tracking and bullet performance were good.
- 1400 yards with Hornady 168 Amax at high altitude. Tracking and bullet performance were fairly good, but I was really pushing the bullet's ability at this distance.
6.5 CM with Hornady 140 ELD-M:
- Good tracking and bullet performance to 1300, maybe 1400 yards, depending on altitude
- Adequate tracking and bullet performance to 1500, maybe 1600 yards, depending on altitude. At this distance I must start adding elevation to the predicted JBM numbers. I suspect the bullet is beginning to show instability, but at the minimum the BC is less than predicted. It's my understanding that BC generally decreases noticeably at velocity decreases.
- Somewhere beyond 1800 yards the bullet performs poorly. In some atmospheric conditions, the bullet appears to fly somewhat consistently. This past weekend at 2000 yards the POI was really inconsistent. Last year at 2100 yards the POI was relatively consistent, but really much lower than JBM predicted.
At really long distances, wind has a much greater effect on elevation. Headwinds require more elevation. Tailwinds reduce elevation requirements. With my right twist barrel, crosswinds from the left require more elevation. Crosswinds from the right require less elevation. Terrain variations can cause the winds to have a vertical aspect, either increasing or reducing elevation needs.
22lr with the best types of 40 grain match ammo
- Good tracking and bullet performance in calm conditions out to 200 yards.
- Pretty good tracking and bullet performance in calm conditions out to 250 yards.
- Beyond 250 yards all bets are off.
I suspect your loads are good out to 600-ish yards because the bullets are flying at a minimum of Mach 1.5, and you have decent MV data and elevation dope. At longer distances I suspect your velocities are below the magic (i.e. bad) Mach 1.25, and thus are going transonic. At transonic and lower velocities, bullet performance deteriorates dramatically, and becomes less predictable. Somewhere around Mach 1.0, many bullets begin wobbling. As velocities decrease further, many bullets tumble.
One more caliber -- 300 BLK:
to 445 yards with SMK 125 and Hornady Vmax 110. For the loads the SBR barrel likes, bullet performance and scope tracking were good to 445 yards -- which is as far as I've shot with the blackout.
|Retired, laying back |
and enjoying life
Thanks fritz, I have learned a lot from you guys. I guess I wasn't as clear as I thought. I'm not faulting the NF as I love them and own several. Just looking at my own learning curve and suggesting a potential shooter problem.
Freedom comes from the will of man. In America it is guaranteed by the 2nd Amendment
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