I've been shooting a Creedmoor for about 3 years. I shot the 139 Lapua for the first barrel's life then switched to the 140 A-Max. The Factory ammo shoots incredibly well.
Shot that group and thought it was lucky so I shot another at the next dot just to see....
Anyway, the factory stuff shoots like that regularly and in one big hole at 100.
I've always done load development. I either shoot an Audette or shoot groups with fully prepped brass and settled on a good load. I'm pretty happy with the load I have now with the same components as the factory ammo, yet the factory stuff shoots as well or better. The thing is that even though I use the same components as the factory, they are different in dimension or weight from the factory. So, I set out on a quest to duplicate the factory ammo and factory ammo performance.
I took 8 factory rounds and carefully measured everything; OAL to the ogive, brass headspace as compared to my fully formed brass etc. I pulled the bullets and weighed the powder charges. 2 at 41gr, 3 at 41.2gr, 2 at 41.3gr, and one at 41.5gr. Crazy for ammo that shoots that well. Concentricity was also an issue with the factory ammo. It still shoots incredibly.
I know I can weigh more consistently, size cases and seat bullets with very little runout and make better ammo dimensionally than the factory stuff.
First, I seated brand new bullets back into the factory cases with their respective charges and wrote the charge weight of each case on it with a marker. The average charge was 41.2gr of H-4350 with the Fed 210M primer and a 140 A-Max seated to about 2.800" OAL or 3.123" on my comparator to the ogive. I then set out to make ammo keeping those parameters the same.
I loaded 30 rounds at 41.2gr H-4350 with the above dimensions in three different "lots" of 10 cases.
The first lot were fully prepped and fireformed cases (uniformed primer pockets, deburred flash holes, neck turned) that I sized in my Redding FL bushing die with the .289 bushing giving around .002" neck tension, shoulders bumped .0015".
The second lot were once fired (fully fireformed) factory cases with no prep. They were sized with a Redding Competition Neck sizer with the .290 bushing.
The third lot were brand new Hornady cases that I simply ran through a Sinclair expander die to try to control (lessen) neck tension. I checked the concentricity of the handloads and all were pretty good, the neck sized ammo had the least runout practically nonexistent.
Then I went to the indoor tunnel range and did some testing.
First, I shot the factory ammo that I had re-seated new bullets into. I shot them at different aimpoints according to how much powder was in the case (the 2 41's at one point, the 3 41.2's at another, etc). They shot like hell and all I did was pull the bullet, weigh the charge, put it back in and seat a brand new bullet. The only two that "grouped" were the 41.3's.
I then shot round robin groups with the three lots until all 10 of each were fired at their respective aimpoint. I let the barrel cool after every 6 shots.
Lot 2 (neck sized only) brass was the best. After the first 5 shots there were 3 holes at about .3" then the group went to an inch after the next 5 were fired.
Lot 1 (Fully Prepped) was a bigger group about the same shape.
Lot 3 (new brass) was terrible
None shot as well as the factory loaded ammo or my developed handload that differs from the factory in charge, OAL, brass dimensions
They must be using some magic at Hornady that I can't figure out.
If anyone else has been able to duplicate the factory ammo dimensions, components, and performance, please tell me the secret!
Shot that group and thought it was lucky so I shot another at the next dot just to see....
Anyway, the factory stuff shoots like that regularly and in one big hole at 100.
I've always done load development. I either shoot an Audette or shoot groups with fully prepped brass and settled on a good load. I'm pretty happy with the load I have now with the same components as the factory ammo, yet the factory stuff shoots as well or better. The thing is that even though I use the same components as the factory, they are different in dimension or weight from the factory. So, I set out on a quest to duplicate the factory ammo and factory ammo performance.
I took 8 factory rounds and carefully measured everything; OAL to the ogive, brass headspace as compared to my fully formed brass etc. I pulled the bullets and weighed the powder charges. 2 at 41gr, 3 at 41.2gr, 2 at 41.3gr, and one at 41.5gr. Crazy for ammo that shoots that well. Concentricity was also an issue with the factory ammo. It still shoots incredibly.
I know I can weigh more consistently, size cases and seat bullets with very little runout and make better ammo dimensionally than the factory stuff.
First, I seated brand new bullets back into the factory cases with their respective charges and wrote the charge weight of each case on it with a marker. The average charge was 41.2gr of H-4350 with the Fed 210M primer and a 140 A-Max seated to about 2.800" OAL or 3.123" on my comparator to the ogive. I then set out to make ammo keeping those parameters the same.
I loaded 30 rounds at 41.2gr H-4350 with the above dimensions in three different "lots" of 10 cases.
The first lot were fully prepped and fireformed cases (uniformed primer pockets, deburred flash holes, neck turned) that I sized in my Redding FL bushing die with the .289 bushing giving around .002" neck tension, shoulders bumped .0015".
The second lot were once fired (fully fireformed) factory cases with no prep. They were sized with a Redding Competition Neck sizer with the .290 bushing.
The third lot were brand new Hornady cases that I simply ran through a Sinclair expander die to try to control (lessen) neck tension. I checked the concentricity of the handloads and all were pretty good, the neck sized ammo had the least runout practically nonexistent.
Then I went to the indoor tunnel range and did some testing.
First, I shot the factory ammo that I had re-seated new bullets into. I shot them at different aimpoints according to how much powder was in the case (the 2 41's at one point, the 3 41.2's at another, etc). They shot like hell and all I did was pull the bullet, weigh the charge, put it back in and seat a brand new bullet. The only two that "grouped" were the 41.3's.
I then shot round robin groups with the three lots until all 10 of each were fired at their respective aimpoint. I let the barrel cool after every 6 shots.
Lot 2 (neck sized only) brass was the best. After the first 5 shots there were 3 holes at about .3" then the group went to an inch after the next 5 were fired.
Lot 1 (Fully Prepped) was a bigger group about the same shape.
Lot 3 (new brass) was terrible
None shot as well as the factory loaded ammo or my developed handload that differs from the factory in charge, OAL, brass dimensions
They must be using some magic at Hornady that I can't figure out.
If anyone else has been able to duplicate the factory ammo dimensions, components, and performance, please tell me the secret!