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Re: The new AR - accuracy [Re: aggiehunter03] #7971451 09/13/20 01:02 AM
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Originally Posted by aggiehunter03
What trigger?
What optic?
Also, try Varget with that GK. My Rock River is 1/2” with 55 and 65 GKs. And those 65s are amazing for a 223 bullet on game.


Both my .223 Wylde and 6.8 Rock Rivers will shoot 3/4 or better with factory ammo.


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Re: The new AR - accuracy [Re: aggiehunter03] #7971452 09/13/20 01:04 AM
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Originally Posted by aggiehunter03
My Rock River is 1/2” with 55 and 65 GKs. And those 65s are amazing for a 223 bullet on game.


Well I'll be. Someone else likes more bullet weight and a tad less velocity for killing.

Who would've thought?


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Re: The new AR - accuracy [Re: FiremanJG] #7971530 09/13/20 02:13 AM
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Originally Posted by FiremanJG
Originally Posted by aggiehunter03
My Rock River is 1/2” with 55 and 65 GKs. And those 65s are amazing for a 223 bullet on game.


Well I'll be. Someone else likes more bullet weight and a tad less velocity for killing.

Who would've thought?


I go heavy in all my rifles. Pretty sure you already knew that though. My kids are 3 for 3 with that 65 GK.
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Re: The new AR - accuracy [Re: 603Country] #7971541 09/13/20 02:31 AM
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Cute little gunners.


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Re: The new AR - accuracy [Re: aggiehunter03] #7971705 09/13/20 12:38 PM
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Originally Posted by aggiehunter03
Also, try Varget with that GK. My Rock River is 1/2” with 55 and 65 GKs. And those 65s are amazing for a 223 bullet on game.

Yup. Try Varget. I also use the 65 GKs and get some amazing groups.

Look at AR15 Performance barrels. I have two of their barrels in a 16" .223 Wylde and a 12.5" 6.8 SPC2 and they're both sub-.5 moa with my reloads. Best of all, they're reasonably priced. Whatever barrel you decide to use, I would also ensure your barrel is bedded to the upper receiver with Loctite 620. I never thought this was a big deal but I'm a believer now. If your barrel is moving in the receiver, you've got no hope for good accuracy.

https://www.ar15performance.com/home

Re: The new AR - accuracy [Re: 603Country] #7972382 09/13/20 10:40 PM
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I have two different 18 inch .223 wylde AR's. Both shoot between .5 to .7 inch groups depending on the day, cleanliness and me. One likes 25.9 grains and the other 26.1 grains of Varget with CCI 450's, Lake City brass with an OAL of 2.260 with 65gr Game Kings. Never really found as good of load with H335/WC844 or TAC with either of these AR's. With lighter 50 and 55grain Vmax bullets yes but not he heavier bullets. I'd call my AR's 1 MOA rifles. On any given day I'll shoot 1 MOA with them but not always the .5-.7 groups at one hundred yards. I can also keep them at or slightly under 2 inches at 200 yards. Never measured the groups at 300 yards.

Last edited by Rcinit; 09/13/20 10:46 PM.

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Re: The new AR - accuracy [Re: TXGUNNER308] #7972998 09/14/20 10:19 AM
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Originally Posted by TXGUNNER308
Originally Posted by Brother in-law
That’s terrible accuracy


^ This

I have a couple ARs that shoot 1/2" MOA with factory match grade ammo.


ARFcom for a while had the "1 MOA all day challenge" for a while, and I suppose it's probably still going. It was a humbling challenge; 5- 5 round groups precludes a lot of the excuses we give ourselves when bragging on the internet. If you've got a rifle that genuinely runs 1/2 MOA beyond a couple 3 shot groups, sell that puppy to some PRS shooter.

Barrel technology and rifle construction has improved significantly over the past few years. I would still not expect a typical consumer grade AR to shoot less than 1 MOA groups consistently- see the challenge above. We've gotten a little too accustomed to an unrealistic standard of accuracy with ARs. In reality, people should be happy with anything 2-3 MOA or less out of a consumer AR, sub 2 MOA when you start tinkering with loads or expensive barrels, and 1 MOA or slightly less when you start spending money on thermofitting and bolt matching.

Of course, there will always be exceptions to the rule. Even a blind dog steps in crap twice per day, or whatever. But when you start chasing accuracy in an AR remember why you can spend a few hundred bucks on a Weatherby and get a 1 MOA bolt action, yet no AR manufacturer in that price range will give the same guarantee.

Last edited by HicksHunter; 09/14/20 10:36 AM.
Re: The new AR - accuracy [Re: 603Country] #7973455 09/14/20 05:15 PM
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The CEO of Black Rain returned my call this morning. Very nice guy. We had a long chat. Accuracy was the main topic, and he said that the Spec15 model that I have should be able to shoot to 1 MOA with the right load. I told him that’s where I am on accuracy, but was honestly hoping for a bit better, but am happy with the rifle.

Unlike the young lady I had spoken to earlier, who told me that I shouldn’t shoot reloads in the Black Rain rifle, the CEO said that wasn’t a problem at all. Either she must be a secretary or his hot girlfriend. She knows nothing about firearms.

And...let me say that I will eventually try some Varget in this rifle - when I can get a pound or two.


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Re: The new AR - accuracy [Re: 603Country] #7973829 09/14/20 10:15 PM
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Is the first round or last round that locks the bolt back causing the group to open up? On any AR, I watch the first round to see if it is hitting high or out of the main group of the next rounds. Also, on the last round where the bolt locks to the rear, sometimes you will get a POI shift from that. To combat this, if I am shooting a 5 shot group, I will load a spare round first that I do not shoot, then load the 5 test rounds on top of this spare round. The spare round will chamber like the rest, but won't change up my POI shift if your AR does this on the last round. I've seen many AR's exhibit one or both of these issues, and you have to figure out if you are seeing this.



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Re: The new AR - accuracy [Re: 603Country] #7973869 09/14/20 10:39 PM
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Originally Posted by 603Country
The Black Rain CEO hasn’t called me yet, so I went back to the workshop. Cleaned the barrel of copper and carbon instead of just carbon. Went to my notes to see what had worked best in earlier shooting. Cold barrel, which is a bit different from yesterday. Trimmed and primed some new Lapua brass. Put 6 rounds in about an inch or a bit more. Nice round group. I can live with that accuracy and not complain too much. The bullet, which I didn’t mention earlier, is that Sierra 65 gr Gameking. A very accurate bullet.

What I have learned is that this rifle and its whippy barrel likes to be clean and cold. I really wanted H335 or BL-C(2) to work because I have plenty of it.

If I decide later to get a better barrel, I’ll consult you long term knowledgeable AR guys.


I get good accuracy with the Sierra 65gr SPT Gameking at 2.255" OAL over either 24.4gr TAC or 23.7gr IMR8208

Re: The new AR - accuracy [Re: ChadTRG42] #7973887 09/14/20 10:47 PM
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Originally Posted by ChadTRG42
Is the first round or last round that locks the bolt back causing the group to open up? On any AR, I watch the first round to see if it is hitting high or out of the main group of the next rounds. Also, on the last round where the bolt locks to the rear, sometimes you will get a POI shift from that. To combat this, if I am shooting a 5 shot group, I will load a spare round first that I do not shoot, then load the 5 test rounds on top of this spare round. The spare round will chamber like the rest, but won't change up my POI shift if your AR does this on the last round. I've seen many AR's exhibit one or both of these issues, and you have to figure out if you are seeing this.


What does the bolt locking to the rear have to do with a POI shift? The bullet is well gone before the bolt reaches anywhere near far enough back to engage the bolt catch, so mechanically there isn't any way for the rifle to "know" its the last round.

Re: The new AR - accuracy [Re: Roughneck913] #7973930 09/14/20 11:04 PM
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Originally Posted by Roughneck913
Originally Posted by ChadTRG42
Is the first round or last round that locks the bolt back causing the group to open up? On any AR, I watch the first round to see if it is hitting high or out of the main group of the next rounds. Also, on the last round where the bolt locks to the rear, sometimes you will get a POI shift from that. To combat this, if I am shooting a 5 shot group, I will load a spare round first that I do not shoot, then load the 5 test rounds on top of this spare round. The spare round will chamber like the rest, but won't change up my POI shift if your AR does this on the last round. I've seen many AR's exhibit one or both of these issues, and you have to figure out if you are seeing this.


What does the bolt locking to the rear have to do with a POI shift? The bullet is well gone before the bolt reaches anywhere near far enough back to engage the bolt catch, so mechanically there isn't any way for the rifle to "know" its the last round.


Yes, the rifle knows. It has to do with the recoil impulse and how the rifle recoils. I can't fully explain the science behind it, but I will 100% guarantee you that it exists in some AR's. It's generally the lower end AR's that show this the most.



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Re: The new AR - accuracy [Re: 603Country] #7973940 09/14/20 11:07 PM
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Maybe Wilson Combat could explain it in detail.



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Re: The new AR - accuracy [Re: ChadTRG42] #7973955 09/14/20 11:20 PM
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Originally Posted by ChadTRG42
Originally Posted by Roughneck913
Originally Posted by ChadTRG42
Is the first round or last round that locks the bolt back causing the group to open up? On any AR, I watch the first round to see if it is hitting high or out of the main group of the next rounds. Also, on the last round where the bolt locks to the rear, sometimes you will get a POI shift from that. To combat this, if I am shooting a 5 shot group, I will load a spare round first that I do not shoot, then load the 5 test rounds on top of this spare round. The spare round will chamber like the rest, but won't change up my POI shift if your AR does this on the last round. I've seen many AR's exhibit one or both of these issues, and you have to figure out if you are seeing this.


What does the bolt locking to the rear have to do with a POI shift? The bullet is well gone before the bolt reaches anywhere near far enough back to engage the bolt catch, so mechanically there isn't any way for the rifle to "know" its the last round.


Yes, the rifle knows. It has to do with the recoil impulse and how the rifle recoils. I can't fully explain the science behind it, but I will 100% guarantee you that it exists in some AR's. It's generally the lower end AR's that show this the most.


Ok, Im going to have to challenge that idea a little bit. Ammo is ammo, whether its the last bullet or first bullet, it does what it does. Removing imperfection within ammo (whole different issue) for a moment to create a scientific "constant," what variable is different specifically about the last round, from say the third or fourth, and the way it interacts with a gun? I cant think of anything mechanical that is different specifically on the last round of a given magazine.

I CAN however think of another cog in the system that changes, and is known to change, and that is the shooter. I see shooters all the time that pull the 5th round shot of an otherwise excellent group, even a small amount, and often in a consistent direction from an individual shooter. This happens a disproportionately large amount of times on the 5th (or whichever is final) shot of a group. And in my experience, it tends to magically goes away if you tell the shooter to do a 7-shot group then cut them off after 5. Now, I realize with a 7 shot group, 7 rounds being loaded=last shot in the mag not being fired, which doesnt directly contradict your claim. But whenever I see something an educated shooter such as yourself (and I mean that fully sincerely, I know you know your [censored]), say there is something they cant quite mechanically explain, I find the answer is usually behind the gun.

Re: The new AR - accuracy [Re: 603Country] #7973980 09/14/20 11:37 PM
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For what it’s worth, the 5th round prints fine from the AR. I will say however, that the 5th round gremlin has followed me around for decades. Many’s the time I’ve had a terrific 4 shot group and dreaded the 5th one.

Tried to order some Varget from the local gun shop. No luck. Said he couldn’t find any from his usual suppliers.


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Re: The new AR - accuracy [Re: Roughneck913] #7974180 09/15/20 02:43 AM
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Originally Posted by Roughneck913
Originally Posted by ChadTRG42
Originally Posted by Roughneck913
Originally Posted by ChadTRG42
Is the first round or last round that locks the bolt back causing the group to open up? On any AR, I watch the first round to see if it is hitting high or out of the main group of the next rounds. Also, on the last round where the bolt locks to the rear, sometimes you will get a POI shift from that. To combat this, if I am shooting a 5 shot group, I will load a spare round first that I do not shoot, then load the 5 test rounds on top of this spare round. The spare round will chamber like the rest, but won't change up my POI shift if your AR does this on the last round. I've seen many AR's exhibit one or both of these issues, and you have to figure out if you are seeing this.


What does the bolt locking to the rear have to do with a POI shift? The bullet is well gone before the bolt reaches anywhere near far enough back to engage the bolt catch, so mechanically there isn't any way for the rifle to "know" its the last round.


Yes, the rifle knows. It has to do with the recoil impulse and how the rifle recoils. I can't fully explain the science behind it, but I will 100% guarantee you that it exists in some AR's. It's generally the lower end AR's that show this the most.


Ok, Im going to have to challenge that idea a little bit. Ammo is ammo, whether its the last bullet or first bullet, it does what it does. Removing imperfection within ammo (whole different issue) for a moment to create a scientific "constant," what variable is different specifically about the last round, from say the third or fourth, and the way it interacts with a gun? I cant think of anything mechanical that is different specifically on the last round of a given magazine.

I CAN however think of another cog in the system that changes, and is known to change, and that is the shooter. I see shooters all the time that pull the 5th round shot of an otherwise excellent group, even a small amount, and often in a consistent direction from an individual shooter. This happens a disproportionately large amount of times on the 5th (or whichever is final) shot of a group. And in my experience, it tends to magically goes away if you tell the shooter to do a 7-shot group then cut them off after 5. Now, I realize with a 7 shot group, 7 rounds being loaded=last shot in the mag not being fired, which doesnt directly contradict your claim. But whenever I see something an educated shooter such as yourself (and I mean that fully sincerely, I know you know your [censored]), say there is something they cant quite mechanically explain, I find the answer is usually behind the gun.



I've seen the last round fired go awry, many times as well. Quite often it will go low. Seen it many times at distance when I'm spotting for someone. I'll see the round splash low, hear that the bolt locked back, and tell the shooter "your mag is empty, isn't it?" Yes, how did you know that?

My theory is the bolt lockes back, robbing gas from the bullet. You say the bullet is gone by then, maybe it isn't.

Listen to a suppressed AR, and pay close attention to the last round fired, it sounds different.


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Re: The new AR - accuracy [Re: 603Country] #7974490 09/15/20 02:15 PM
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Roughneck, I understand it's a hard concept to understand, and I can not explain it fully either. I shoot thousands of rounds a year. I see many AR's and I test a lot of firearms. My job when dialing in a rifle is to make it shoot the best it can and eliminating the variables that cause bullets to not go where I want. In an AR, the first round POI shift and the last round bolt lock back is 100% legit. I have seen it over and over. I will always load one extra round in the mag as a follower when testing an AR for groups.



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Re: The new AR - accuracy [Re: 603Country] #7974514 09/15/20 02:32 PM
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I use a magazine sled to single load AR's.... that way I am already prepared just in case Biden wins... cool


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Re: The new AR - accuracy [Re: 603Country] #7974545 09/15/20 02:45 PM
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Chad, I can understand the theory of that last round being low or otherwise out of the group, but a 1st round POI shift is less understandable. Can you give me some causation logic for that.

Being new to the non-government owned AR game, this is all news to me. I’ll have to pay a bit more attention to whether or not I see these issues with this rifle. I haven’t noticed them so far, but that doesn’t mean much.


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Re: The new AR - accuracy [Re: 603Country] #7975808 09/16/20 03:27 AM
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[/quote] , Im going to have to challenge that idea a little bit. Ammo is ammo, whether its the last bullet or first bullet, it does what it does. Removing imperfection within ammo (whole different issue) for a moment to create a scientific "constant," what variable is different specifically about the last round, from say the third or fourth, and the way it interacts with a gun? I cant think of anything mechanical that is different specifically on the last round of a given magazine.

I CAN however think of another cog in the system that changes, and is known to change, and that is the shooter. I see shooters all the time that pull the 5th round shot of an otherwise excellent group, even a small amount, and often in a consistent direction from an individual shooter. This happens a disproportionately large amount of times on the 5th (or whichever is final) shot of a group. And in my experience, it tends to magically goes away if you tell the shooter to do a 7-shot group then cut them off after 5. Now, I realize with a 7 shot group, 7 rounds being loaded=last shot in the mag not being fired, which doesnt directly contradict your claim. But whenever I see something an educated shooter such as yourself (and I mean that fully sincerely, I know you know your [censored]), say there is something they cant quite mechanically explain, I find the answer is usually behind the gun.[/quote]


I've seen the last round fired go awry, many times as well. Quite often it will go low. Seen it many times at distance when I'm spotting for someone. I'll see the round splash low, hear that the bolt locked back, and tell the shooter "your mag is empty, isn't it?" Yes, how did you know that?

My theory is the bolt lockes back, robbing gas from the bullet. You say the bullet is gone by then, maybe it isn't.

Listen to a suppressed AR, and pay close attention to the last round fired, it sounds different.[/quote]

The bullet is absolutely gone before lock back, or even the bolt being fully unlocked. that isn't really debatable. watch any super slo-mo video of an AR. Watch the one linked below, 1:17 mark. If the bullet is gone before the bolt cycles even 1/4 of the way (which it is) , there is NO mechanical difference from second to last round to last round. and the idea of "robbing" gas doesnt really make sense to me either- the last round produces no more or less gas, and the amount of gas it uses it decided before the bolt unlocks, and WELL before the bolt passes the catch, so the idea that it bleeds extra gas only on last-rounds doesnt really hold water to me. and the last round on a suppressor sounding different makes perfect sense because sound doesnt travel linearly, and your arent re-sealing the back end of the sound chamber when the bolt hold open, so hearing some "echoes" reverberating back to you through the chamber rather than all the noise being from the muzzle would be a perfectly reasonable explanation for the last shot sounding different. but again, the bullet it long gone at this point, so I dont see how any of that would have a ballistic impact

https://lockedback.com/slow-motion-cutaway-footage-ar-15/

Last edited by Roughneck913; 09/16/20 03:29 AM.
Re: The new AR - accuracy [Re: Roughneck913] #7975824 09/16/20 04:22 AM
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I sure as hell can't explain it, but I can tell you they are right. Look, I usually don't count my rounds so half the time I don't KNOW when I'm on my last round so it's nothing intentional on my part. But I've been there with Jason as my spotter and seen it happen, and like he noted he could tell I was at the end of the mag before I knew it. I wouldn't have thought it made a difference either but I know from experience it does.

Earl

Originally Posted by Roughneck913
[/quote] , Im going to have to challenge that idea a little bit. Ammo is ammo, whether its the last bullet or first bullet, it does what it does. Removing imperfection within ammo (whole different issue) for a moment to create a scientific "constant," what variable is different specifically about the last round, from say the third or fourth, and the way it interacts with a gun? I cant think of anything mechanical that is different specifically on the last round of a given magazine.

I CAN however think of another cog in the system that changes, and is known to change, and that is the shooter. I see shooters all the time that pull the 5th round shot of an otherwise excellent group, even a small amount, and often in a consistent direction from an individual shooter. This happens a disproportionately large amount of times on the 5th (or whichever is final) shot of a group. And in my experience, it tends to magically goes away if you tell the shooter to do a 7-shot group then cut them off after 5. Now, I realize with a 7 shot group, 7 rounds being loaded=last shot in the mag not being fired, which doesnt directly contradict your claim. But whenever I see something an educated shooter such as yourself (and I mean that fully sincerely, I know you know your [censored]), say there is something they cant quite mechanically explain, I find the answer is usually behind the gun.



I've seen the last round fired go awry, many times as well. Quite often it will go low. Seen it many times at distance when I'm spotting for someone. I'll see the round splash low, hear that the bolt locked back, and tell the shooter "your mag is empty, isn't it?" Yes, how did you know that?

My theory is the bolt lockes back, robbing gas from the bullet. You say the bullet is gone by then, maybe it isn't.

Listen to a suppressed AR, and pay close attention to the last round fired, it sounds different.[/quote]

The bullet is absolutely gone before lock back, or even the bolt being fully unlocked. that isn't really debatable. watch any super slo-mo video of an AR. Watch the one linked below, 1:17 mark. If the bullet is gone before the bolt cycles even 1/4 of the way (which it is) , there is NO mechanical difference from second to last round to last round. and the idea of "robbing" gas doesnt really make sense to me either- the last round produces no more or less gas, and the amount of gas it uses it decided before the bolt unlocks, and WELL before the bolt passes the catch, so the idea that it bleeds extra gas only on last-rounds doesnt really hold water to me. and the last round on a suppressor sounding different makes perfect sense because sound doesnt travel linearly, and your arent re-sealing the back end of the sound chamber when the bolt hold open, so hearing some "echoes" reverberating back to you through the chamber rather than all the noise being from the muzzle would be a perfectly reasonable explanation for the last shot sounding different. but again, the bullet it long gone at this point, so I dont see how any of that would have a ballistic impact

https://lockedback.com/slow-motion-cutaway-footage-ar-15/[/quote]


Re: The new AR - accuracy [Re: 603Country] #7975858 09/16/20 10:11 AM
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Here's my thinking on the last shot conundrum. It's a fact that the first shot and the last shot fire under the exact same conditions and bolt lockup- you wouldn't like the hole in the side of your gun if the bolt was opening before the bullet was long gone.

But what about feeding? ARs feed violently, as evidenced by scratches on the bullet and case after being stripped from the magazine. There is a slight difference between how the last round is handled during feeding as it may be held in a different position by the follower, and it'll feed with less friction. So maybe the last round isn't so beat up during feeding, and doesn't suffer from scratches or a slight change in COAL.

So that's one explanation for what can be different between the first and last rounds. My take? It's all in our heads, and this is just a case of confirmation bias where we look past all the times that the last round groups perfectly.

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Re: The new AR - accuracy [Re: 603Country] #7976671 09/16/20 07:57 PM
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(I started a new thread so I didn't hijack this thread)

https://texashuntingforum.com/forum/ubbthreads.php/topics/7976727#Post7976727


Alright, let's talk about this last round, bolt lock back on an AR-15 rifle. I just so happened to have a rifle in for load development with an AR-15 in 6.5 Grendel, about a 18" barrel shooting suppressed. The lower is a Palmetto State lower, and I'm not sure what the barrel is. Overall, and very nice AR. I loaded up the test loads with a 123 SST in Hornady brass and CCI #450 primer. The main picture is the entire target with test loads from A to F. I shot loads A through D with a 6th round follower to avoid the bolt lock back. Just for poops and giggles, I went ahead and shot test loads E and F with only 5 rounds in the mag so the bolt would lock to the rear on the 5th shot.

All shot at 100 yards.
Load A shot really well. A .764", 5 shot group, with 6th round loaded as a follower.
Load B and C are stringing and we are out of the accuracy node.
Load D had 3 nice tight shots, but they didn't come in sequence and the group was a little open. I figured I would come into another node on E or F.
Load E, I shot 5 rounds, with the 5th round locking the bolt to the rear. Load E had 4 shots in a .854" group and the 5th round with the bolt locking to the rear went high left. The group opened up to 1.355", 5 shot group. During normal testing, I would NOT load the 5 rounds and shoot 5 rounds. My first round in the mag would be my last follower round, and I would load my 5 test loads on top of that.
Load F shot a 4 shot .733" group and the 5th round bolt lock to the rear opened it up to 1.197", and the round went left.
Conclusion= both Load E and F shot very well 4 shot groups, but the 5th round bolt lock to the rear caused a POI shift. This rifle appears to go left, and maybe slightly high, but certainly left. I gave all groups an honest group to shoot them my best. I was shooting off a front sand bag and rear sand bag, and "driving" the rifle nice and tight.

So what caused this? The recoil impulse is totally different on the last round bolt lock back. The rifle is upset with this change in recoil impulse. What specifically causes the POI shift, I'm not 100% sure. But what I can tell you is, that it is 100% legit and you will NEVER find me shooting a precision shot with the last round locking back, if I can plan ahead on my round counts.

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Last edited by ChadTRG42; 09/16/20 08:23 PM.


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Re: The new AR - accuracy [Re: 603Country] #7976927 09/16/20 11:05 PM
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I am going to have to try this with my AR. This should be interesting.


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