Started my journey with more serious load development for my SPRish AR a few months ago. I've reloaded for about 6 years now, and while i've tried to make more accurate ammo and whatnot, I've never truly taken the precision reloading and long(er) range shooting seriously. Since I've joined this forum and gotten back into more serious reloading I've focused on my SPR type AR and figured i'd start there, and then move onto my 6.5cm bolt gun next. Currently the 147gr ELD-m factory ammo shoot great in my 6.5 so I'll just stick with those for now.
I'd like to state this is for my own personal gain and improvement as a shooter and as a reloader. I would like to do more coyote hunting, and hitting steel at longer ranges, out to 750yds (what I have available). I may also do some small mini PRS type matches at my gun club(300yd max). Any input is helpful and appreciated. I very open to adjusting or trying different things, and some times it helps to get other, more experienced shooters opinions on expectations and improvements.
Any way, rifle specs are:
-Older Rock River Arms complete lower with Geissele SSA-E trigger
-LAR Side charged upper (very tight fit on lower)
-Lothar Walthar 18" 1:8 SPR barrel
-Surefire SOCOM suppressor (always on the rifle)
-Vortex PST 2.5-10
I've read the sticky points on this forum for reloading precision ammo and its given me a lot to think about and review in my process. I also understand that this isn't a fully custom AR and my precision shooting skill is novice-intermediate, so I try to have as realistic expectations as possible. I just like to have input from other shooters using my situations, as I do not have many shooters around my area, and I'm relatively new to my gun club.
My brass prep consists of:
-LC Brass, cleaned/polished
-Weighed to 91.5-92.8gr (this essentially just gets rid of outliers)
-Flash hole deburred
-Primer pocket uniformed
-mouth chamfered
-All trimmed uniformly
Initial Load Development was done at 100 yds and consisted of using Ramshot TAC under Sierra 77gr TMK, Nosler 77gr CC, and 73gr. ELD-M. I also introduced RL 15 powder as well. Primer is always Rem. 7 1/2. For 100yd development I used ES/SD using my cheap ProChrono and group size as a combo in decision making. Across all powders and bullets, 2600fps really seemed like a good "node", as well as around 2740fps, however I did not test a lot there to avoid worrying about pressure, and to just focus on one thing at a time. All 100yd development yielded consistent 1/2-3/4moa 3 shot groups, and 3/4-1moa 5 shot groups, at least with my skill (or lack there of) that is.
After narrowing down the 2600fps node, I went with the TMK and the ELD-M, and took those out to 400yds on a calm day. Across 4-5, 5-shot groups, my results weren't very exciting, giving me 5-6in groups with a lot of vertical spread. I went back to the bench and redid my load development with RL15, and pushed upwards in the velocity until I found my pressure ceilings. After reading more on ladder testing I decided to do ladder testing at 400yds with the TMK and the ELD-M. THis is where it gets better, but also left me still trying to decide what to go with.
The 73gr ELD-m ladder testing using RL15 was super interesting to do, and learned a good bit. I narrowed the initial ladder test to these 4 grain charges.
I ended up sticking with 24.3gr RL15 and that produced roughly MOA 5 shot groups at 400yds. As I do testing I usually do 2, 5shot groups with chrono graph. The whole 10shot group was about 6in, however there was obviously 2 bad fliers to the left. There's also more vertical stringing to the 73gr. ELD-M load, which I was wondering if it could be that i'm not quite in the node of 2740 that I have seen in the rifle. Groups below: The vertical stringing is pretty normal for this load, however the 2 fliers to the left were abnormal. SD for this load across 10 shots was 10, which makes me like the load and think that hte vertical stringing may be more of a node issue.
Now on to the 77gr. TMK. I worked up to 24.6gr TAC which is just under NATO max and my brass shows very mild signs of pressure. Mildly flattened primers, no cratering, and a very slight ejector mark. This load produced very little vertical, and averages 2740fps pretty consistently. This definitely seems like the best load, and at 400yds did the best overall, taking into consideration all variables. SD's for this sit around 10-14.
The group had 3 little fliers off to the left, which I feel like was a great 3 shot group, and most likely was my cheekweld/position/etc that may have pushed them consistently to the left. The low round round seems like the only real flier.
So this is where I have trouble deciphering through the mix between shooter error, loading error, and actual data. I understand that if I was a perfect shooter there would probably be closer winner. I do have about 180 TMK bullets left, so I'd like to load those up with the 24.6gr. TAC and see what I can do with more chronograph data and working on my shooting position/fundamentals.
Does anyone see something here I don't , or maybe give any advice on how to move forward from here.
Appreciate any and all advice.
Thanks
I'd like to state this is for my own personal gain and improvement as a shooter and as a reloader. I would like to do more coyote hunting, and hitting steel at longer ranges, out to 750yds (what I have available). I may also do some small mini PRS type matches at my gun club(300yd max). Any input is helpful and appreciated. I very open to adjusting or trying different things, and some times it helps to get other, more experienced shooters opinions on expectations and improvements.
Any way, rifle specs are:
-Older Rock River Arms complete lower with Geissele SSA-E trigger
-LAR Side charged upper (very tight fit on lower)
-Lothar Walthar 18" 1:8 SPR barrel
-Surefire SOCOM suppressor (always on the rifle)
-Vortex PST 2.5-10
I've read the sticky points on this forum for reloading precision ammo and its given me a lot to think about and review in my process. I also understand that this isn't a fully custom AR and my precision shooting skill is novice-intermediate, so I try to have as realistic expectations as possible. I just like to have input from other shooters using my situations, as I do not have many shooters around my area, and I'm relatively new to my gun club.
My brass prep consists of:
-LC Brass, cleaned/polished
-Weighed to 91.5-92.8gr (this essentially just gets rid of outliers)
-Flash hole deburred
-Primer pocket uniformed
-mouth chamfered
-All trimmed uniformly
Initial Load Development was done at 100 yds and consisted of using Ramshot TAC under Sierra 77gr TMK, Nosler 77gr CC, and 73gr. ELD-M. I also introduced RL 15 powder as well. Primer is always Rem. 7 1/2. For 100yd development I used ES/SD using my cheap ProChrono and group size as a combo in decision making. Across all powders and bullets, 2600fps really seemed like a good "node", as well as around 2740fps, however I did not test a lot there to avoid worrying about pressure, and to just focus on one thing at a time. All 100yd development yielded consistent 1/2-3/4moa 3 shot groups, and 3/4-1moa 5 shot groups, at least with my skill (or lack there of) that is.
After narrowing down the 2600fps node, I went with the TMK and the ELD-M, and took those out to 400yds on a calm day. Across 4-5, 5-shot groups, my results weren't very exciting, giving me 5-6in groups with a lot of vertical spread. I went back to the bench and redid my load development with RL15, and pushed upwards in the velocity until I found my pressure ceilings. After reading more on ladder testing I decided to do ladder testing at 400yds with the TMK and the ELD-M. THis is where it gets better, but also left me still trying to decide what to go with.
The 73gr ELD-m ladder testing using RL15 was super interesting to do, and learned a good bit. I narrowed the initial ladder test to these 4 grain charges.
I ended up sticking with 24.3gr RL15 and that produced roughly MOA 5 shot groups at 400yds. As I do testing I usually do 2, 5shot groups with chrono graph. The whole 10shot group was about 6in, however there was obviously 2 bad fliers to the left. There's also more vertical stringing to the 73gr. ELD-M load, which I was wondering if it could be that i'm not quite in the node of 2740 that I have seen in the rifle. Groups below: The vertical stringing is pretty normal for this load, however the 2 fliers to the left were abnormal. SD for this load across 10 shots was 10, which makes me like the load and think that hte vertical stringing may be more of a node issue.
Now on to the 77gr. TMK. I worked up to 24.6gr TAC which is just under NATO max and my brass shows very mild signs of pressure. Mildly flattened primers, no cratering, and a very slight ejector mark. This load produced very little vertical, and averages 2740fps pretty consistently. This definitely seems like the best load, and at 400yds did the best overall, taking into consideration all variables. SD's for this sit around 10-14.
The group had 3 little fliers off to the left, which I feel like was a great 3 shot group, and most likely was my cheekweld/position/etc that may have pushed them consistently to the left. The low round round seems like the only real flier.
So this is where I have trouble deciphering through the mix between shooter error, loading error, and actual data. I understand that if I was a perfect shooter there would probably be closer winner. I do have about 180 TMK bullets left, so I'd like to load those up with the 24.6gr. TAC and see what I can do with more chronograph data and working on my shooting position/fundamentals.
Does anyone see something here I don't , or maybe give any advice on how to move forward from here.
Appreciate any and all advice.
Thanks
