There seems to be no shortage of threads about flyers on this forum so I apologize for adding mine to the list but I wanted to share it with everyone because the pattern was so consistent. I’m working up a hunting load for my Remington 700p in 300 Win Mag. The barrel has been shortened to 20” and I shoot suppressed with a SilencerCo Hybrid. Everything else about the rifle is stock. I’m using a Nightforce NXS 3.5-15 x 50 mm scope with beefy scope rings on a Nightforce 20 MOA picatinny rail. I’m using ABM brass, H1000, Hornady 212 gr ELD-X bullets and CCI 250 primers. I full length resized the brass with a Hornady Custom Grade die (with an elliptical expander). I chamfer and deburred the case mouths, prime using a Frankford Arsenal Perfect Primer hand primer, carefully load powder with an RCBS balance beam scale that’s been calibrated with a check weight set, and seat the bullets with a Hornady Custom Grade die. I seat them 0.124” off the lands so they’ll fit in PMAGs (I want to swap the stock for a chassis with a DBM some day). I’ve played around with seating depths going from 0.020 off the lands to 0.124” and the 0.124’s can group just as good as the others in my rifle.
From my initial load development I saw a good group at 77.7 gr of H1000 (see Chart 1). I loaded up some more rounds honing in around the 77.7 gr range. I loaded three 3-round groups at 77.6, 77.7 and 77.8 gr for a total of 27 rounds using the same method as described previously.
I cleaned my barrel using a carbon cleaner (M Pro7), cleaning rod and bore guide. When I got to the range I shot 6 foulers (3 with factory HSM ammo and 3 with factory ABM). Interestingly the groups weren’t that great, but there didn’t seem to be any flyers with either of these 3-shot groups (see Target1).
I was shooting off front and rear sand bags that weren’t too full. I typically used the rear bag for elevation adjustment. My chronograph was a Labradar. I shot a 3-round group and then let the barrel cool for ~5 min while I shot my other rifle. As you can see in Target2 each and every 3-shot group has the same pattern. 2 shots that are touching (or almost touching) with a 3rd shot that’s a flyer. I just thought that was an amazing coincidence that all nine 3-shot groups exhibited that same pattern. By the way the 3rd shot was not always the flyer. Sometimes it was the 1st or 2nd shot. And although I didn’t document which shot on the target corresponded to which muzzle velocity I want to say I didn’t see a correlation at the range. At the range I would take the shot and then look at the Labradar. Sometimes I would see a high or low MV and think it would be a flyer only to look through my scope and see it touching the other bullet hole. Also the flyers seemed to be in a random orientation relative to the two "good" shots.
From Chart 2 you can see I’m getting the best groups with 77.8 gr this time. Also as has been mentioned on other threads in this forum there’s no correlation between ES’s and group size (see Chart 3). Interestingly my average muzzle velocity did not increase going from 77.7 to 77.8 grains. Median MV did not increase either.
From reading other threads about flyers some of the remedies that members have suggested include switching to neck sizing using a collet die, checking bullets for consistency of ogive length, free floating the barrel, changing the barrel, adjusting the firmness of the sand bags and ensuring a consistent shooting position (to list a few).
The fact that the first two 3-shot groups with the factory ammo did not seem to have flyers like my hand loads suggests to me that the problem lies in my hand loads themselves and not in the rifle or shooting technique. So I guess I’ll just have to go through my reloading components and processes one by one until I find the culprit.
So any suggestions on where to start? I really like the ELD-X’s but I’m open to Bergers or others. It seems like lots of people get good results using H1000 with 300 Win Mag so I would think it’s not the powder. Do match primers really make a difference? Should I be checking concentricity? Deburring flash holes? Oy, the list goes on and on…

77.6 2793
77.6 2811
77.6 2831
77.6 2818
77.6 2828
77.6 2842
77.6 2825
77.6 2833
77.6 2856
77.7 2835
77.7 2844
77.7 2854
77.7 2840
77.7 2849
77.7 2860
77.7 2842
77.7 2846
77.7 2864
77.8 2842
77.8
77.8 2851
77.8 2837
77.8 2844
77.8 2865
77.8 2840
77.8 2847
77.8 2859
From my initial load development I saw a good group at 77.7 gr of H1000 (see Chart 1). I loaded up some more rounds honing in around the 77.7 gr range. I loaded three 3-round groups at 77.6, 77.7 and 77.8 gr for a total of 27 rounds using the same method as described previously.
I cleaned my barrel using a carbon cleaner (M Pro7), cleaning rod and bore guide. When I got to the range I shot 6 foulers (3 with factory HSM ammo and 3 with factory ABM). Interestingly the groups weren’t that great, but there didn’t seem to be any flyers with either of these 3-shot groups (see Target1).
I was shooting off front and rear sand bags that weren’t too full. I typically used the rear bag for elevation adjustment. My chronograph was a Labradar. I shot a 3-round group and then let the barrel cool for ~5 min while I shot my other rifle. As you can see in Target2 each and every 3-shot group has the same pattern. 2 shots that are touching (or almost touching) with a 3rd shot that’s a flyer. I just thought that was an amazing coincidence that all nine 3-shot groups exhibited that same pattern. By the way the 3rd shot was not always the flyer. Sometimes it was the 1st or 2nd shot. And although I didn’t document which shot on the target corresponded to which muzzle velocity I want to say I didn’t see a correlation at the range. At the range I would take the shot and then look at the Labradar. Sometimes I would see a high or low MV and think it would be a flyer only to look through my scope and see it touching the other bullet hole. Also the flyers seemed to be in a random orientation relative to the two "good" shots.
From Chart 2 you can see I’m getting the best groups with 77.8 gr this time. Also as has been mentioned on other threads in this forum there’s no correlation between ES’s and group size (see Chart 3). Interestingly my average muzzle velocity did not increase going from 77.7 to 77.8 grains. Median MV did not increase either.
From reading other threads about flyers some of the remedies that members have suggested include switching to neck sizing using a collet die, checking bullets for consistency of ogive length, free floating the barrel, changing the barrel, adjusting the firmness of the sand bags and ensuring a consistent shooting position (to list a few).
The fact that the first two 3-shot groups with the factory ammo did not seem to have flyers like my hand loads suggests to me that the problem lies in my hand loads themselves and not in the rifle or shooting technique. So I guess I’ll just have to go through my reloading components and processes one by one until I find the culprit.
So any suggestions on where to start? I really like the ELD-X’s but I’m open to Bergers or others. It seems like lots of people get good results using H1000 with 300 Win Mag so I would think it’s not the powder. Do match primers really make a difference? Should I be checking concentricity? Deburring flash holes? Oy, the list goes on and on…





77.6 2793
77.6 2811
77.6 2831
77.6 2818
77.6 2828
77.6 2842
77.6 2825
77.6 2833
77.6 2856
77.7 2835
77.7 2844
77.7 2854
77.7 2840
77.7 2849
77.7 2860
77.7 2842
77.7 2846
77.7 2864
77.8 2842
77.8
77.8 2851
77.8 2837
77.8 2844
77.8 2865
77.8 2840
77.8 2847
77.8 2859