I've got a 13.9" AR pinned to 16" with a DA flash hider. I'm trying to get a heavier load worked up for it and so far I've been nowhere near successful. Goal is to be as close to a MOA rifle as possible. Have not found an accurate load yet for this rifle with factory or handloaded ammo.
Rifle Specs
I have a MAWL and Surefire light on the end and a LAW folder with a VLTOR EMOD stock so it is about 12 lbs with the optic and mag. Should be very steady. Below are key components:
Reloading Process
I've been reloading for a while now, and have managed to put a load together for my 6.5 Creed (AR10, 18" Criterion barrel) that shoots 140 HPBT at 2589 fps with an ES of 25 and SD of 9.2. I've got multiple groups right at 1" at 100 yds with this rifle (same scope) so I think my technique is good. I am using the same process (different components obviously) to load for my 556. See attached photo on brown paper for 6.5 Creed groups.
I trim brass (Layman) and measure charges on a RCBS traditional scale. Seating / resizing is done with RCBS dies. My BTO measurements are within 0.003" for each length I have loaded to. Based on what I see on the scale, my charge weights are typically within 0.05gr.
Shooting Setup
Front bag and a set of heavy pants as the rear bag. I find this helps me adjust between rifles and saves me $30 I would otherwise spend on a rear bag. Shooting prone off concrete into a target stapled to a sheet of OSB and held steady by fence posts. Parallax is always checked on the scope before shooting. Conditions haven't ever been perfectly still, but any wind that was there was generally constant and my groups were very rarely seeing more horizontal than vertical spread. I also have a 20" RRA that shoots great and I've shot factory VMAX's into 0.75 MOA in the past.
Results so Far
I've done a ladder test with CCI 450 primers, RP brass, TAC and 77 SMKs. I loaded 0.2gr increments from 23.8gr to 24.8gr (max). Along the way I was able to find a couple good nodes for speed speed (ES of 35 to 50 fps and SD of 8.6 to 20). However, all groups were 2 MOA or larger. I have had similar results from factory ammo (match grade) and even sent the barrel back to Larue when it was still a 16" barrel and they sent it back with a target proving it was under 1 MOA.
After dry firing a bit, I thought maybe my technique was off with the AR15 and somehow I'm shooting the 6.5 better than the 223. I loaded up 2 sets of loads today with the same components as above but I substituted 77gr Hornady HPBTs. I practiced dry fire until my reticle didn't move and then shot the 10 rounds I had loaded up with 25.6gr and 25.8gr of TAC. ES of 41 and 47 with SD of 15 and 16.8. See target attached on white paper. This group was at approximately 80 yards and is 1.66" (2.1 MOA).
Discussion
Is there anything that jumps out to you guys that would cause me to have these issues? Anything else I should be doing or measuring to ensure good results?
As you can see in both pictures, I will sometimes get a group with two pairs almost touching and a fifth somewhere on its own. This leads me to believe I may have a technique issue, but I'm not sure what else I can do to lock things down.
The fact that I haven't found a good factory or hand load leads me to believe I may have a 1.5 to 2 MOA barrel. I could try a different powder, but I've got so much TAC that I would probably be better off buying a different barrel as I was hoping to load about 1,500 rounds of the SMK / TAC combo. I'm very close to having Compass Lake spin up a 13.9" Criterion and have them install / headspace it to this upper and be done with it but want to make sure I'm not missing something before I spend that money.
Rifle Specs
I have a MAWL and Surefire light on the end and a LAW folder with a VLTOR EMOD stock so it is about 12 lbs with the optic and mag. Should be very steady. Below are key components:
- 13.9" Larue Stealth (cut and pinned by ADCO)
- Seekins adjustable gas block
- Dead Air flash hider
- RRA upper lapped with Brownells lapping tool
- BCM KMR13 torqued to 60 ft/lbs
- RRA bcg
- Mark 5 3.6-18 optic with TMR reticle
- Geissele SSA-E
- MOE K2+ grip for a more shallow grip angle
Reloading Process
I've been reloading for a while now, and have managed to put a load together for my 6.5 Creed (AR10, 18" Criterion barrel) that shoots 140 HPBT at 2589 fps with an ES of 25 and SD of 9.2. I've got multiple groups right at 1" at 100 yds with this rifle (same scope) so I think my technique is good. I am using the same process (different components obviously) to load for my 556. See attached photo on brown paper for 6.5 Creed groups.
I trim brass (Layman) and measure charges on a RCBS traditional scale. Seating / resizing is done with RCBS dies. My BTO measurements are within 0.003" for each length I have loaded to. Based on what I see on the scale, my charge weights are typically within 0.05gr.
Shooting Setup
Front bag and a set of heavy pants as the rear bag. I find this helps me adjust between rifles and saves me $30 I would otherwise spend on a rear bag. Shooting prone off concrete into a target stapled to a sheet of OSB and held steady by fence posts. Parallax is always checked on the scope before shooting. Conditions haven't ever been perfectly still, but any wind that was there was generally constant and my groups were very rarely seeing more horizontal than vertical spread. I also have a 20" RRA that shoots great and I've shot factory VMAX's into 0.75 MOA in the past.
Results so Far
I've done a ladder test with CCI 450 primers, RP brass, TAC and 77 SMKs. I loaded 0.2gr increments from 23.8gr to 24.8gr (max). Along the way I was able to find a couple good nodes for speed speed (ES of 35 to 50 fps and SD of 8.6 to 20). However, all groups were 2 MOA or larger. I have had similar results from factory ammo (match grade) and even sent the barrel back to Larue when it was still a 16" barrel and they sent it back with a target proving it was under 1 MOA.
After dry firing a bit, I thought maybe my technique was off with the AR15 and somehow I'm shooting the 6.5 better than the 223. I loaded up 2 sets of loads today with the same components as above but I substituted 77gr Hornady HPBTs. I practiced dry fire until my reticle didn't move and then shot the 10 rounds I had loaded up with 25.6gr and 25.8gr of TAC. ES of 41 and 47 with SD of 15 and 16.8. See target attached on white paper. This group was at approximately 80 yards and is 1.66" (2.1 MOA).
Discussion
Is there anything that jumps out to you guys that would cause me to have these issues? Anything else I should be doing or measuring to ensure good results?
As you can see in both pictures, I will sometimes get a group with two pairs almost touching and a fifth somewhere on its own. This leads me to believe I may have a technique issue, but I'm not sure what else I can do to lock things down.
The fact that I haven't found a good factory or hand load leads me to believe I may have a 1.5 to 2 MOA barrel. I could try a different powder, but I've got so much TAC that I would probably be better off buying a different barrel as I was hoping to load about 1,500 rounds of the SMK / TAC combo. I'm very close to having Compass Lake spin up a 13.9" Criterion and have them install / headspace it to this upper and be done with it but want to make sure I'm not missing something before I spend that money.
