5.56 ammo guidance

[Gatordev]

I've been perusing the threads here (again), but looks like most of the ammo/accuracy threads pertain to .308. So...

I'm looking for some suggestions on how to research ammo for certain barrels. I have a BCM middy 14.5" and have been shooting a couple different brands of ammo. I haven't been able to find much with Google that specifically addresses brand of ammo w/ the barrel. According to BCM (and "internet experts"), this rifle w/ the 1:7 twist should like 62 gr or higher the best. Obviously the various makes of ammo have some variation as well.

So far, I've fired a bunch of Privi M855, PMC XTAC M855, and some Wallyworld Remington UMC 55gr. I only had 50 rounds of the Remington, but at 25 yards (when sighting in) and at 100 yards, that seemed to be the most consistent of the three. The PMC is a close second and the Privi...well at 100 yards, it looks like a shotgun blast.

Now, understand I am COMPLETELY aware the shooter has to do his part. If there's anyone who can get a "Most Improved Award" for AR shooting at 100 yards, I'm sure it's me. But I'm trying to help eliminate some of the "inaccuracy" of the ammo so that I can concentrate on identifying issues and fixing the shooter.

As for "real-world" performance... I can head over to the ~200 yard range w/ a bunch of steel hanging targets and reliably hit them (with my Xmas optic gift to myself) with all three types of ammo, and I understand the 14.5" AR is a "battle rifle" and not made to be a 7EET sniper rifle, but just looking for some better consistency.

So should I play w/ the 55 gr more? Is there some other ammo I should look at (that's not match grade ammo at $1 per round)? Or should I just be happy w/ the PMC and enjoy killing evil steel?

 

[gaijin6423]

What were the WX conditions, in general. It's not far enough that pressure and temp would be a factor, but was it overcast or bright? Were you comfortable, temp wise, and were you shooting supported or one of the more traditional positions? What was the pattern like, shape and location wise?

 

[statesman]

Fixed your 1337 sp43k for you.

I understand the 14.5" AR is a "battle rifle" and not made to be a 1337sniper rifle

As to your question... Have you tried setting your rifle up in a rest / block to ensure you are taking yourself fully out of the equation? If your adamant about finding the absolute best ammunition you may want to consider it.

Also you may want to consider going even heavier. I dont have a 1:7 AR yet (in the process of building one with a Daniel Defense barrel) but I have a Remington 700 LTR with a 1:7 that is supposed to be sub 1/2 MOA but I can't get anywhere close to that with anything lighter than 72gr and even then I have to hand load them. For your AR you might want to just try a few rounds of something really heavy just to get an idea of what it likes to shoot. After you know for sure, then you can choose on a daily basis if you are going to the range to just sling lead, or if you want to drive tacks at 400yds

 

[CAMike]

Gatordev- Perspective example.

I have my 20" Krieger Barreled Upper (1 in 7.7 twist rate in Stainless Steel) that I've dialed in hand loads to 3/4" @ 100 yards on a bad day and 1/2" groups @100 if I'm doing my part.

About a year and a half ago I was curious to see how Brand X ammo would perform in this upper. So I ran 20 rounds each though it. Privi 62g, Remington 55g and XM193 55g all at @ 100Yards. NONE of them broke 1". If memory serves, all brands were inconsistent around the bulls eye and the spreads varied from 1 1/4" to about 2 1/2" with some random impacts creating as much as a 2 3/4" spread on certain targets. The XM was by far the worst but then what would you expect from that kind of ammo. These 3 brands were performing to about MILSPEC standards and that's exactly what one would expect. If you want under an inch accuracy I'd highly recommend hand loading some 69 grain and 77 grain loads with either Nosler Custom Competition's or Sierra brand bullets. RL15, Varget or IMR 8208XBR are all good powders to start off with.

If you don't want to or don't have the ability to make your own hand loads, I'd be willing to bet the Federal Gold Medal Match in either 69g or 77g would be pretty close to hand load performance. GMM is expensive ($26 to $30 per 20 rounds) so cost may become a limiting factor in that option. I've never tried the GMM's so I can't speak to those. Maybe someone else can speak to the GMM's in the follow on posts.

 

[Gatordev]

What were the WX conditions, in general. It's not far enough that pressure and temp would be a factor, but was it overcast or bright? Were you comfortable, temp wise, and were you shooting supported or one of the more traditional positions? What was the pattern like, shape and location wise?

The temp today when I was shooting was probably 55-60. It was rainy out, although during the time I was shooting there weren't any showers. I'm sure we were hovering around 80-90% humidity. It was windy/gusty out, but I think the berms were taking care of most of that. When I was down at the target, there just a light breeze. When I was shooting at the ~200 yard range (it's around 170-200 depending how far back into the trees you go), it was probably windier since it's just an open field with two berms on two sides.

On the 100 yard range, I was shooting from the bench with the rifle resting on a wood ammo box. I don't have any sand bags. I tried shooting both with my hand on top of the handguard as well as on the mag well and the results were about the same. I was shooting at a printed ACOG target on a 8 1/2 x 11 sheet of paper. They were mostly latterly spaced with some below the bullseye. I could probably use a click or two up. There were one or two flyers, but if you compare it to a NRA target (SR-1), the majority were inside the 9-ring with half of them inside the 10 ring. While shooting at the steel on the ~180 yard range, I was just sitting in the back of my 4Runner, supporting the rifle on my knee. I need to get a sling to help out with non-bench shooting. That's on my list for my next parts/ammo/lower purchase.

Fixed your 1337 sp43k for you.

Damn. I haz no skillz. I dont play teh COD.

As to your question... Have you tried setting your rifle up in a rest / block to ensure you are taking yourself fully out of the equation? If your adamant about finding the absolute best ammunition you may want to consider it.

Also you may want to consider going even heavier. I dont have a 1:7 AR yet (in the process of building one with a Daniel Defense barrel) but I have a Remington 700 LTR with a 1:7 that is supposed to be sub 1/2 MOA but I can't get anywhere close to that with anything lighter than 72gr and even then I have to hand load them. For your AR you might want to just try a few rounds of something really heavy just to get an idea of what it likes to shoot. After you know for sure, then you can choose on a daily basis if you are going to the range to just sling lead, or if you want to drive tacks at 400yds

Honestly, at the end of the day, all I'm doing is slinging led. Part of my interest and reason for getting into rifles has been to learn and as a result, I of course want to improve. I'm just trying to take out some of the inherent error so it's easier for me to see my own error. And again, I understand it's a 14.5" barrel, so I know it's not going to drive tacks like a nice match 18 or 20".

Gatordev- Perspective example.

I have my 20" Krieger Barreled Upper (1 in 7.7 twist rate in Stainless Steel) that I've dialed in hand loads to 3/4" @ 100 yards on a bad day and 1/2" groups @100 if I'm doing my part.

About a year and a half ago I was curious to see how Brand X ammo would perform in this upper. So I ran 20 rounds each though it. Privi 62g, Remington 55g and XM193 55g all at @ 100Yards. NONE of them broke 1". If memory serves, all brands were inconsistent around the bulls eye and the spreads varied from 1 1/4" to about 2 1/2" with some random impacts creating as much as a 2 3/4" spread on certain targets. The XM was by far the worst but then what would you expect from that kind of ammo. These 3 brands were performing to about MILSPEC standards and that's exactly what one would expect. If you want under an inch accuracy I'd highly recommend hand loading some 69 grain and 77 grain loads with either Nosler Custom Competition's or Sierra brand bullets. RL15, Varget or IMR 8208XBR are all good powders to start off with.

If you don't want to or don't have the ability to make your own hand loads, I'd be willing to bet the Federal Gold Medal Match in either 69g or 77g would be pretty close to hand load performance. GMM is expensive ($26 to $30 per 20 rounds) so cost may become a limiting factor in that option. I've never tried the GMM's so I can't speak to those. Maybe someone else can speak to the GMM's in the follow on posts.

I just don't have the time to research and then handload right now. I agree, that's probably a more reliable way to go, but there's lots of other competing distractions, work being the majority of them. I certainly get what you're saying, though. I believe (and correct me here if I'm wrong) that MILSPEC is around 2 MOA for a M4. I'm probably sitting at 4 MOA-ish with the PMC, which isn't that much out of the box with the unskilled labor behind the rifle. And I can still reliably hit slightly smaller-width-than-man-sized steel targets at ~180-200 yards, which is far more satisfying than that silly paper. But again, I'm just trying to get better.

Sounds like when I buy my next batch of 5.56, I'll throw a box or two of the "good stuff" in there to try out.

 

[Rocketman]

I agree, it sounds like you've been getting "mil-spec" type accuracy from "mil-spec" type ammo. I'd try some of the heavier Black Hills stuff while you are experimenting. That's pretty good stuff for factory ammo.

Also just a comment on barrel length and accuracy. I'm no bench shooter but IMHO there probably isn't any mechanical reason a shorter barrel can't shoot just as accurately as a longer barrel. Some would even argue that a shorter barrel is stiffer and might be capable of better mechanical accuracy than a longer tube. Can I shoot a 20" AR with iron sights more accurately at 300-500yrds than a 16/14.5" AR? Yup, but in my mind that may have more to do with a longer sight radius that a longer barrel.

 

[gaijin6423]

I'm with Rocketman on the barrel length issue. As far as the Marine Corps was concerned, I could shoot both barrel profiles equally as well from the 300-500 yard range. Counterintuitively, I shot Table 3 (short range, reactionary type shooting is as good a way to describe it as any) with an M16A2 with iron sights, and shot better than everyone else on the range.

I had asked about the overcast/bright and comfort factors earlier, because they can play havoc with sight picture, how good your position is, trigger control, etc. Consistency is as important as any other component that contributes to accuracy, which is something that it took me a while to learn. Well, that and patience.

Believe it or not, if you're on paper with the ACOG one your first couple attempts, you're doing a he'll of a lot better than some people out there. The shit you see on a Marine rifle range...

 

[Rocketman]

I'm with Rocketman on the barrel length issue. As far as the Marine Corps was concerned, I could shoot both barrel profiles equally as well from the 300-500 yard range. Counterintuitively, I shot Table 3 (short range, reactionary type shooting is as good a way to describe it as any) with an M16A2 with iron sights, and shot better than everyone else on the range.

I had asked about the overcast/bright and comfort factors earlier, because they can play havoc with sight picture, how good your position is, trigger control, etc. Consistency is as important as any other component that contributes to accuracy, which is something that it took me a while to learn. Well, that and patience.

Believe it or not, if you're on paper with the ACOG one your first couple attempts, you're doing a he'll of a lot better than some people out there. The shit you see on a Marine rifle range...

I love the way the Marine Corps does rifle qual now. The old KD course of fire is great for teaching solid fundamentals but a tight sling doesn't do you much good in close quarters. I was a grunt but I can count on one hand the number of times we did any realistic/practical rifle training in Jimmy Carter's Marine Corps.

 

[gaijin6423]

Unfortunately, the ideas behind Tables 2 and 3 of the combat marksmanship program only really work when done through lots and lots of repetition. The average Marine these days--combat arms and associated direct support folks--just don't get the repetition they need to build muscle memory to noticeable effect. And then there's the whole concept of the 'hammer pair', which was a gross (and kind of stupid) misunderstanding of top competitive shooters by the Marine Corps. Thankfully, I think it has gone away. Still, the program is leaps and bounds beyond what what taught when I went through recruit training, and some of the more advanced schools like High Risk Personnel (HRP) are pretty damn sweet.

 

[C420sailor]

I agree, it sounds like you've been getting "mil-spec" type accuracy from "mil-spec" type ammo. I'd try some of the heavier Black Hills stuff while you are experimenting. That's pretty good stuff for factory ammo.

Also just a comment on barrel length and accuracy. I'm no bench shooter but IMHO there probably isn't any mechanical reason a shorter barrel can't shoot just as accurately as a longer barrel. Some would even argue that a shorter barrel is stiffer and might be capable of better mechanical accuracy than a longer tube. Can I shoot a 20" AR with iron sights more accurately at 300-500yrds than a 16/14.5" AR? Yup, but in my mind that may have more to do with a longer sight radius that a longer barrel.

Assuming that sight radius isn't a factor (with an optic, for example), I still think the longer barrel will be more accurate. The longer barrel will provide increased velocity at longer ranges. This prevents the projectile from going subsonic and losing stability prior to impacting the target. Short barrels lose a decent bit of muzzle velocity, which translates to an earlier supersonic to subsonic transition.

 

[Gatordev]

Let me try this again since someone flicked the switch last night on the server...

Can I shoot a 20" AR with iron sights more accurately at 300-500yrds than a 16/14.5" AR? Yup, but in my mind that may have more to do with a longer sight radius that a longer barrel.

Well, I guess the important part is actually being able to SEE the front sight. Something that gets hard with my "aging" eyes. I still don't understand how guys can see and shoot as accurately as they can at 300 yards with iron sights. To me, that's really damn impressive. I know it's just another day for guys who do it all the time.

Believe it or not, if you're on paper with the ACOG one your first couple attempts, you're doing a he'll of a lot better than some people out there. The shit you see on a Marine rifle range...

Really? The ACOG just seems to make it so easy. Once I got it on paper and towards the center at 25 yards, it's pretty straight-forward. I'm definitely a fan, and I'm by no means a Marine rifleman.

I love the way the Marine Corps does rifle qual now. The old KD course of fire is great for teaching solid fundamentals but a tight sling doesn't do you much good in close quarters. I was a grunt but I can count on one hand the number of times we did any realistic/practical rifle training in Jimmy Carter's Marine Corps.

This brings up another aspect of my original question. I first learned to shoot GI M-16s with the GI strap wrapped around my arm for both prone and indian style (whatever that's called). I was thinking of getting something like a TACSTRAP (modified MS2 type strap) as a way to stabalize when you don't have a bench to make everything easy. Are you guys recommending not going that route? Obviously I'm not kicking in doors, just doing the range thing, but not always with a bench when shooting at range. Or should I just break down and get a VFG and quick complaing?

 

[gaijin6423]

In another thread, we were talking about the fore grip (the action, not necessarily the component). There is a school of thought, perpetuated by competitive shooters and Magpul instructors, that you can use a slightly rotated, slightly extended grip on the fore end of the rifle to lock the rifle into your shoulder. It's nowhere near as tight as a loop sling in a prone or sitting position, but it works well at short ranges and in rapid, dynamic firing situations. It is more of a tacticool kind of thing though.

The ACOG, while a great tool, has befuddled many. Most of the issues I've seen while zeroing them revolve around someone getting issued a rifle from someone else without it being returned to true zero, improper eye relief, and not understanding the reticle. I've also had someone freak out because they didn't understand the Bindon Aiming Concept, which can screw with you a bit when you're shooting close range stuff. Until you get over it, that is.

 

[Rocketman]

Well, I guess the important part is actually being able to SEE the front sight. Something that gets hard with my "aging" eyes. I still don't understand how guys can see and shoot as accurately as they can at 300 yards with iron sights. To me, that's really damn impressive. I know it's just another day for guys who do it all the time.

I have a problem "seeing" the front sight post as well. My eyes keep changing back and forth. As of right now I can see the front sight post on a 16" barrel but can barely see the fookin front sight assembly on a 20". A year ago it was the opposite.

Assuming you can see (and no wind LOL), shooting well at 300-500 yds on a KD course is mostly just good monkey skills. Not much Zen to it. Good dope on the weapon, a tight sling/natural point of aim, consistent trigger pull and a good sight picture are all it takes to make hits. However, shooting well in the wind is a different story for me......Wind and rain? Better give me an M203.

I haven't shot any high power events (Garand, M1A, AR15 on the KD course) in maybe 10 years. That's the last time I used a tight sling. Now if I'm shooting at any distance at all I take advantage of anything I can to steady up. Sand bag, backpack, ammo can. What ever works.

 

[Gatordev]

In another thread, we were talking about the fore grip (the action, not necessarily the component). There is a school of thought, perpetuated by competitive shooters and Magpul instructors, that you can use a slightly rotated, slightly extended grip on the fore end of the rifle to lock the rifle into your shoulder. It's nowhere near as tight as a loop sling in a prone or sitting position, but it works well at short ranges and in rapid, dynamic firing situations. It is more of a tacticool kind of thing though.

I remember that thread. I haven't tried an AFG, but forgetting that for a second, the Magpul/tacticool method looks like a great idea, but it's just not comfortable for me after a little while. Holding my arm up like that starts to get tiring compared to having something to rest my hand on (like some sort of grip). Maybe if there was something there to rest my hand against it would help. I may just grab a TACSTRAP and see how I like it.

Now, for the SBR that I'm just starting to assemble parts for...I'm pretty sure that will get a VFG of some sort. Then I can be a 1337 snipa.

Thanks for the pointers, guys. I'd love to go shooting with you guys someday, just to pick up the scraps of knowledge you leave on the ground with the brass. Oh wait, some of you guys reload...