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Posted: 9/24/2017 9:56:11 PM EDT
Here is the rifle. I put it together from parts. Mega receiver's, Kreiger barrel, Timney trigger
 Attached FilePowder used is Varget, bullet is Sierra 168 HPBT, Lake City Brass. All shots fired at 200 yds with 2 minutes between each shot. I started by loading 5 rnds each beginning at 42.3 - 43.2 in increments of .3. My two best targets were 42.9 and 43.2 by far. I then loaded 43.0, 43.1...43.3, & 43.4 and went and shot. Here are the targets. It's interesting how you get scatter, tight, scattered, tight. (I say tight, I know many of you fella's "tight" is a lot tighter than mine. I'm ~2moa shooter, but getting better.)  Attached File Attached File Attached File Attached File |
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Posted: 9/24/2017 9:57:34 PM EDT
[#1]
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Posted: 9/24/2017 10:08:57 PM EDT
[#2]
What cases, primer, and what powder are you using?
Also, what is your jump to lands distance? |
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Posted: 9/24/2017 10:14:07 PM EDT
[#3]
Powder is Varget, Cases are Lake City. I can't remember the primers as these cases were processed some time ago. I can look.
No idea how far from the lands. Tool on order to be able to gauge that. I loaded them at whatever reloading manual said was max length, 2.80 I think. |
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Posted: 9/24/2017 11:47:13 PM EDT
[#4]
My thoughts, for what they're worth. No offense is meant, I'm just being frank -
1. Your charge weights are too close together. If you had chrono data, I'd bet they are almost indistinguishable. 0.25 gr to 0.5 gr would be a better step. Question - With what level of precision were the charges weighed/thrown? 2. The explosion in group size when going from 42.9 to 43.0 gr is beyond credibility. To me, it implies something is wrong with the rifle and/or sights or possibly the shooter. 3. Given the charge weights are almost the same, I'm wondering if what we are seeing is your ability at shooting groups. 4. What is unusual is the point of impact walks steadily downward with increasing charge weight. I'll go look at the targets again and may have additional thoughts. |
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Posted: 9/25/2017 1:17:25 AM EDT
[#5]
I don't think a self-professed 2 MOA shooter should be doing load testing at 200 yards.
My advice is to start over. - Shoot at 100 yards - Turn the target backwards and use shoot 'n see stickers so all charges are shot on 1 target. You want precise aiming points if you're trying to shoot precise groups. - Shoot "round robin" style to eliminate variables between groups. |
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Posted: 9/25/2017 2:03:00 AM EDT
[#6]
I agree with the last couple posts.
You should not see a big difference in group size using Varget with such little difference in charge weight. My loads in .308 Win both for bolt action rifles and for the M1A show very little difference in group size even going up or down 1 full grain in charge weight. This is true using several different powders including Varget. As just mentioned also you are much better off testing at 100 yards than 200. Even light breezes can be trouble at 200 when group testing. You don't want outside forces influencing your results. You need a good solid rest to shoot groups from. Sometimes I'll use my Lead Sled. Not because of recoil control but simply because it's a good solid rest. I'm always torn when developing loads in a semiautomatic. Do I load them one at a time, directly into the chamber, one at a time stripped from the magazine or, ? Is a hard choice but usually I go with one at a time stripped from the magazine. But after I think I found an accurate load I'll shoot a group with all rounds loaded in the magazine. I figure that's how the rifle is going to be used in the real world so I need to know how it's going to act in the real world. Motor |
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Posted: 9/25/2017 10:42:29 AM EDT
[#7]
Charges were weighed using a RCBS charge master.
I can go to 100 yds, but everything I've read on developing a load says shoot at 200 so that it shows the difference in groups better. I already shot in .3 gr increments. I thought I'd see what difference there was in .1 increments between the two best targets. |
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Posted: 9/25/2017 10:43:42 AM EDT
[#8]
Quote HistoryQuoted:
I agree with the last couple posts. You should not see a big difference in group size using Varget with such little difference in charge weight. My loads in .308 Win both for bolt action rifles and for the M1A show very little difference in group size even going up or down 1 full grain in charge weight. This is true using several different powders including Varget. As just mentioned also you are much better off testing at 100 yards than 200. Even light breezes can be trouble at 200 when group testing. You don't want outside forces influencing your results. You need a good solid rest to shoot groups from. Sometimes I'll use my Lead Sled. Not because of recoil control but simply because it's a good solid rest. I'm always torn when developing loads in a semiautomatic. Do I load them one at a time, directly into the chamber, one at a time stripped from the magazine or, ? Is a hard choice but usually I go with one at a time stripped from the magazine. But after I think I found an accurate load I'll shoot a group with all rounds loaded in the magazine. I figure that's how the rifle is going to be used in the real world so I need to know how it's going to act in the real world. Motor |
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Posted: 9/25/2017 12:38:29 PM EDT
[#9]
Quote HistoryQuoted:
As just mentioned also you are much better off testing at 100 yards than 200. Even light breezes can be trouble at 200 when group testing. You don't want outside forces influencing your results. I'm always torn when developing loads in a semiautomatic. Do I load them one at a time, directly into the chamber, one at a time stripped from the magazine or, ? Is a hard choice but usually I go with one at a time stripped from the magazine. But after I think I found an accurate load I'll shoot a group with all rounds loaded in the magazine. I figure that's how the rifle is going to be used in the real world so I need to know how it's going to act in the real world. Motor Regarding wind: the group sizes seem dominated by elevation changes, not wind. Wind may be in there but the big problem to diagnose and eliminate is that causing the wild swings in elevation. What I do is load and shoot one at a time. When I have my best candidate load, I'll then shoot from a magazine of twenty rounds. This not only ensures the same grouping but also verifies feed and function. This is how I start to deal with your concept of "real world" application. |
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Posted: 9/25/2017 12:45:21 PM EDT
[#10]
Quote HistoryQuoted:
I don't think a self-professed 2 MOA shooter should be doing load testing at 200 yards. My advice is to start over. - Shoot at 100 yards - Turn the target backwards and use shoot 'n see stickers so all charges are shot on 1 target. You want precise aiming points if you're trying to shoot precise groups. - Shoot "round robin" style to eliminate variables between groups. I don't think there's anything wrong with shooting at 200 yards but it is more difficult. The thing is, his "problem" seems to be elevation not windage. Once he gets that squared away, he can come to grips with the effect of wind on his point of impact at 200 yards. One more question - how hot and humid was it that day? Could really heavy mirage in a no wind condition cause the elevation to be that far off? It's unlikely but I thought I'd ask. I know a ~10 mph cross wind is worth about 3-4" at 200 yards. Smaller changes can easily cause his lateral dispersion but the problem is elevation. Final question for this post - did you call all your shots? Were they on call? |
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Posted: 9/25/2017 1:53:52 PM EDT
[#11]
Better Target ie Champion Redfield Sight in Target is my choice. Make sure you bench and rest are solid!
The OP needs to know what primer etc. Brass should be sorted by headstamp. Keep separate from other rifles brass. After 5 firing pitch it! Varget and BR2 from CCI is primo! 1 percent increments in the 308 is about right so increment should be 0.4gr Forget chasing the lands shoot at COAL near mag length such as 2.60". The 168 is meant to jump. And, does very well as evidence in Fed GM ammo is the benchmark |
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Posted: 9/25/2017 2:18:32 PM EDT
[#12]
Thanks for all the comments!
I don't even own a shooting bench and never will. I shoot everything from prone. The rifle was sand bagged. Wife and I teach Appleseed so I understand the 6 steps to firing the shot and natural point of aim. Doesn't mean I can do it, just I understand the concepts! 
There was no wind yesterday, but a very heavy mirage. I'm thinking I will do the test again and see if the pattern stays with loads shot previously. |
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Posted: 9/25/2017 2:19:48 PM EDT
[#13]
Quote HistoryQuoted:
I agree about having a better target. When I use these targets for testing, I use the numbers "in the white" as my point of aim not the center of the X ring. I made a custom target for load testing. I don't think there's anything wrong with shooting at 200 yards but it is more difficult. The thing is, his "problem" seems to be elevation not windage. Once he gets that squared away, he can come to grips with the effect of wind on his point of impact at 200 yards. One more question - how hot and humid was it that day? Could really heavy mirage in a no wind condition cause the elevation to be that far off? It's unlikely but I thought I'd ask. I know a ~10 mph cross wind is worth about 3-4" at 200 yards. Smaller changes can easily cause his lateral dispersion but the problem is elevation. Final question for this post - did you call all your shots? Were they on call? |
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Posted: 9/25/2017 7:47:28 PM EDT
[#14]
I am impressed you are able to go over 43 gr with Varget in LC brass. Thats too hot for my AR10, I get ejector swipes over 42.5. I like to shoot 10 shot groups when I am testing loads. As I am an imperfect shooter, that gives me a better feel for the potential. When you get 5 of 10 stacked on top of each other and the other 5 with more spread that leads me to experiment more with that load than when I get none of the 10 on top of the others. I also dont do the 1 minute between shots stuff. I take 10 well aimed shots at a normal cadence. I do allow some time between strings.
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Posted: 9/26/2017 3:24:37 PM EDT
[#15]
Quote HistoryQuoted:
I am impressed you are able to go over 43 gr with Varget in LC brass. Thats too hot for my AR10, I get ejector swipes over 42.5. I like to shoot 10 shot groups when I am testing loads. As I am an imperfect shooter, that gives me a better feel for the potential. When you get 5 of 10 stacked on top of each other and the other 5 with more spread that leads me to experiment more with that load than when I get none of the 10 on top of the others. I also dont do the 1 minute between shots stuff. I take 10 well aimed shots at a normal cadence. I do allow some time between strings.  LOL
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Posted: 9/26/2017 3:32:53 PM EDT
[#16]
Creighton Audette developed his OCW approach with Benchrest rifles.
The level of precision necessary to resolve accurate data from an OCW test demands an extremely accurate rifle from the get go. |
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Posted: 9/26/2017 6:33:47 PM EDT
[#17]
I would try 40.5, 41.0, 41.5 and 42.0 maximum in Lake City brass.
.5 grains represents close to 30 fps change in velocity with most powders in .308 when using 168's. I use 40.7 grains of IMR-4064, 40.2 grains of IMR-4895 or 41.5 grains of VihtaVuori N150 when loading 168's in Lake City. My loads all generate close to 2600 fps from a 26" barrel bolt action. That's a maximum load in my book when using Lake City brass. |
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Posted: 9/26/2017 6:41:30 PM EDT
[#18]
Based on what we see of your target: If you are honestly a 2 MOA shooter and staying within 1-300yds, I would just use the tried and true 168 Service load. 41.5 grains of Varget in LC brass with any brand 168 is easy shooting and doesn't need to be perfectly trickled, just thrown. Work on practice-and that includes dryfire practice.
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Posted: 10/1/2017 12:54:02 AM EDT
[#19]
Quote HistoryQuoted:
I don't even own a shooting bench and never will. I shoot everything from prone. The rifle was sand bagged. Wife and I teach Appleseed so I understand the 6 steps to firing the shot and natural point of aim. Doesn't mean I can do it, just I understand the concepts!
There was no wind yesterday, but a very heavy mirage. I'm thinking I will do the test again and see if the pattern stays with loads shot previously. If I'm shooting a number of loads for testing I'll still shoot prone but use a heavy bag up front to stabilize it. Otherwise fatigue sets in and this may be the same thing you're encountering. You may be taking too long of a break between rounds fired making you anxious to get it over which coupled with the heat & mirage is also fatiguing both physically and mentally and affecting group size. On top of that the shifting angle of the sun changing lighting and maybe shadows can affect your perception of the sight picture and eye alignment behind the scope (parallax) all of which would also affect group size. Hope that helps! |
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Posted: 10/1/2017 2:41:23 AM EDT
[#20]
Quote HistoryQuoted:
I did not. I didn't go down after each shot fired and no way I could keep in my head the called shots. Never try to keep shot calls in your head - write them down. I mark each shot call on a tiny target (1/2" diameter, one per shot). I plot the actual impacts on a larger target face (4" diameter). There is no way powder charge and/or case weight variations could cause that much vertical dispersion at 200 yards. That much vertical would require 500 fps or 1,000 fps variation (just a guess to make the point). Barrel vibrations do not change the POI that much with 0.1 gr powder charge changes, something else did it. My guess is it is the shooter, either directly the shooter or the shooter as influenced by the conditions. My guess is conditions. Heavy mirage with no wind (as evidenced by the low lateral dispersion) can throw off your vertical. It could even be mirage off your barrel (but unlikely). Mirage is the only hypothesis I have for why your vertical would vary so much between shots. A tiny amount of wind (a few mph, even a tail wind) can then blow out the mirage, make the target appear fully round again and help with consistency in actual sight alignment (as opposed to apparent sight alignment thrown off by mirage). Without a scope you cannot track mirage. Get a spotting scope. It is most useful for watching the wind conditions (as evidenced by blowing grass stalks and mirage). |
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Posted: 10/1/2017 4:42:27 PM EDT
[#21]
This isn’t OCW testing, you are just shooting separate groups of different charge weights.
If you are a 2 MOA shooter (or you gun is only capable of 2moa), OCW isn’t for you. That may sound harsh, but I dont want to see anyone wasting money. The target isnt going to tell you what you need to know with any degree of confidence if you have an additional potential of ~4in of shooter error. |
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Posted: 10/1/2017 6:49:12 PM EDT
[#22]
Those rifles are just harder to get small groups with because of all that is going on, they need perfect follow through IMO. If you shot that same ammo out of a decent bolt action I bet the groups would be a lot smaller.
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Posted: 10/1/2017 8:18:33 PM EDT
[#23]
Quote HistoryQuoted:
Those rifles are just harder to get small groups with because of all that is going on, they need perfect follow through IMO. If you shot that same ammo out of a decent bolt action I bet the groups would be a lot smaller. What scope is the OP using? Is it a bad/malfunctioning scope? |
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Posted: 10/1/2017 9:30:24 PM EDT
[#24]
Thank you all for the insight. As stated before, there was a heavy mirage and that may have played a part.
The theory of fatigue mentioned is something I didn't think about. It takes a while to shoot that many rounds and laying on concrete (even with a mat) in the hot sun for that long has to have an influence. I may, just for fun, do it again and see if it's consistent. If I do and it's the same outcome, I don't think it's me. We'll see. IF I ever get time to do it again!!! |
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Posted: 10/1/2017 9:36:18 PM EDT
[#25]
Quote HistoryQuoted:
Huh? Please explain further. My AR's can all shoot ~1 MOA right out of the box. I don't think this is a rifle problem but am willing to listen to why you think it is. What makes you think this is a rifle problem? What scope is the OP using? Is it a bad/malfunctioning scope? |
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Posted: 10/1/2017 10:52:50 PM EDT
[#26]
Quote HistoryQuoted:
Thank you all for the insight. As stated before, there was a heavy mirage and that may have played a part. The theory of fatigue mentioned is something I didn't think about. It takes a while to shoot that many rounds and laying on concrete (even with a mat) in the hot sun for that long has to have an influence. I may, just for fun, do it again and see if it's consistent. If I do and it's the same outcome, I don't think it's me. We'll see. IF I ever get time to do it again!!! |
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Posted: 10/2/2017 9:42:49 AM EDT
[#27]
My "theory" is that if it's me as the shooter, the pattern won't be the same. I'll "throw" the shots on a different load or two.
What I'd like to do, but would struggle to get time to do it, is to load the same loads and shoot each one on a different day. |
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Posted: 10/2/2017 9:57:00 AM EDT
[#28]
Tell us about the scope. Its very difficult to shoot .5 MOA if your scope does not have the power to aim (repeatedly aim) within .5 MOA at the distance. It is far more difficult to shoot .5 MOA with a heavy duplex 4x than it is with a fine crosshair 20X.
When I am working up loads at 200, I am 20X or more. Cranked to the max. Get better targets. Print them off the internet. Get targets that help with aiming. I like T's or diamonds. And, the target should be one that allows you to easily distinguish your cross hairs/reticle. Don't shoot out your point of aim. Dial it 2 inches to the left or the right. That way, you still have a pristine point of aim. The big elevation change could be a result of big swings in the charges. Or, it could result from a failure to control the butt. If you want to shoot prone to test loads, sand bag the front and sand bag the rear with a rabbit/bunny ear bag. Bag the weapon so that you can get up, walk away, and return and the reticle is still on target. And, you have to maintain a constant hold/recoil resistance. Elevation swings can be caused by changes in your hold pressure. With a free sliding AR15 on bags, my groups move over an inch in verticle at 200yds. Same MOA for the group, just at a different point of impact on the target relative to firm recoil resistance. |
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Posted: 10/2/2017 11:54:20 AM EDT
[#29]
Quote HistoryQuoted:
Huh? Please explain further. My AR's can all shoot ~1 MOA right out of the box. I don't think this is a rifle problem but am willing to listen to why you think it is. What makes you think this is a rifle problem? |
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Posted: 10/2/2017 12:15:28 PM EDT
[#30]
Quote HistoryQuoted:
I don't believe he's saying semi-autos aren't accurate, it's that they are more difficult to shoot accurately. Of all my "accurate" rifles, the AR pattern .308 is the most difficult to get a good group out of. Quote HistoryQuoted:
I don't believe he's saying semi-autos aren't accurate, it's that they are more difficult to shoot accurately. Of all my "accurate" rifles, the AR pattern .308 is the most difficult to get a good group out of. Quoted:
Have you shot a lot of large frames? |
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Posted: 10/2/2017 1:08:49 PM EDT
[#31]
Guessing,
"Large" frame = 308 size AR 10. "Small" frame = 223 size AR15 |
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Posted: 10/2/2017 2:38:20 PM EDT
[#32]
Quote HistoryQuoted:
Guessing, "Large" frame = 308 size AR 10. "Small" frame = 223 size AR15 The characteristic I find intriguing in this thread is the dispersion happens only in the vertical. Even in the big groups, the horizontal dispersion is unaffected. This is why I do not think it is the ammo. The horizontal dispersion is also consistent with the OP's claim as a 2 MOA shooter. Butt pad loose in the shoulder but everything else is good = good theory. It's easy to make this mistake and the recoil impulse (not the moving bolt) can get you if you do it. |
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Posted: 10/2/2017 9:58:59 PM EDT
[#33]
Quote HistoryQuoted:
Tell us about the scope. Its very difficult to shoot .5 MOA if your scope does not have the power to aim (repeatedly aim) within .5 MOA at the distance. It is far more difficult to shoot .5 MOA with a heavy duplex 4x than it is with a fine crosshair 20X. When I am working up loads at 200, I am 20X or more. Cranked to the max. Get better targets. Print them off the internet. Get targets that help with aiming. I like T's or diamonds. And, the target should be one that allows you to easily distinguish your cross hairs/reticle. Don't shoot out your point of aim. Dial it 2 inches to the left or the right. That way, you still have a pristine point of aim. The big elevation change could be a result of big swings in the charges. Or, it could result from a failure to control the butt. If you want to shoot prone to test loads, sand bag the front and sand bag the rear with a rabbit/bunny ear bag. Bag the weapon so that you can get up, walk away, and return and the reticle is still on target. And, you have to maintain a constant hold/recoil resistance. Elevation swings can be caused by changes in your hold pressure. With a free sliding AR15 on bags, my groups move over an inch in verticle at 200yds. Same MOA for the group, just at a different point of impact on the target relative to firm recoil resistance. What makes me hesitant to think it though is I don't think that explains the inconsistent targets. I was shooting round the rosy style so that would mean that in the two vertically dispersed targets I just happened to do a poor job of controlling the buttstock on those two targets only when I came to them. That is a bit unlikely. |
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Posted: 10/14/2017 12:32:25 AM EDT
[#34]
Next time I would set up some wind flags, add a buttstock weight so the rifle balances better on the rest, and shoot early morning when the mirage isn't present. I suspect the heavy mirage was causing the extreme vertical you got.
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Posted: 10/14/2017 1:02:20 AM EDT
[#35]
Did you start at 42.3 gr or work up to that? That seems a bit hot for LC brass. At least assuming it's typical military brass. Did you chrono your loads?
I've been working up loads in IMI brass. I started with 40 gr of Varget (below min) using 168 gr Nosler CC. Mine clocked at about 2400 fps out of an 18" barrel. Out of a 24" bolt gun they would have likely been a bit hotter than Hodgdon's data for 41 gr. My 42 gr loads were just about filling the case. May have been slight compression. 43 gr seems pushing it. I don't have a lot of shot data yet, but the pic below is at 100 yrds with some wind and TWO different loads - 3 at 40.0 gr and 5 at 40.5 gr. I have no idea which are which but 0.5 gr clearly had very little impact on where and how they grouped. That group measured right at 2 MOA. Also keep in mind an AR is hard on ammo. Load up some dummy rounds and chamber them from a mag. The bullets get beat up a little which probably isn't good for overall accuracy. 2 MOA is probably a reasonable expectation. EDIT: oh, also I was shooting about 1 shot every 5-10 seconds except for the time it took to reload the mag between the two charge weights. Obviously not ideal for testing. 
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