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shawnmt,
My preface to this entire discussion is that I have had vigorous and animated arguments with people who insist that a 223 / 556 won't even go 1000yds....their ignorance is dumbfounding.
Impressive shooting. As a new member here but an old one at shooting the AR, it is always impressive to see folks push the limits of their equipment. Posts like this are infinitely more interesting than a lot of the other topicis - I like accurate rifles.
That being said - I have considerable experience in shooting, winning and building 1K service rifles - mostly AR's. In your discussion, I wholeheartedly agree with your point that you had a good lot of 855. This point bears repeating. Not all M-855 is created equal, much less the same. I've shot 10's of thousands of rounds of 855 (new US GI LC stuff) and it varies enormously lot to lot. The issue is the the penetrator core's location inside - if it is off center, it will result in a external ballistic anomoly called nutation. Bullets that transition to subsonic will exhibit another (or in addition to nutation) anomaly called precession - this basically will induce yaw and result in keyholing. The import / M855 clone type ammo includes a LOT of suspect loadings and QC. Bad bullets are a sure recipe for massive frustration at range. Some ammo labeled as M-855 do not include the penetrator core. Others that do have it, but it is hopelessly off center.
Another aspect of successful 1K shooting is velocity variance - ES or SD, however one wishes to quantify it - small velocity variances are enormaously helpful. A 20-30fps variance will result in elevation stringing of at least 1-1.5 moa at 1K (11-16 inches). Bottom line - good M-855 is / can be VERY good ammo. Regarding the M-193 - I am actually more impressed with your results from that. Even at 600yds - it is really / actually ballistically unstable. Kudos there. Impressive feat.
I would offer for your consideration however, that the 80 Sierra isn't the bullet of choice for 1K. Even when loaded as a single round (long OAL) there are far better choices. High BC bullets will do far better at range since they don't shed velocity like their high drag breatheren. The 80 SMK or even the 90 SMK are not up there as a better choice. Bullets like the 80 or 90gr VLD's will preform circles around an 80 HPBT. For those that just lept out of their chairs with their BS flags at the ready - claiming these are outer stratosphere custom bullets requiring all sorts of special gizmos and whizbang twists, I say settle back down. It may sound that way - but they really are not. I have tested hundreds of bullets in all sorts of twists and land/groove arrangements. A 90gr VLD will shoot and stabilize out of a standard milspec 1/7 bbl. Now I am not saying you'll get the same accuracy as a custom barrel, but you get far better performance out of this bullet choice than trying to get an 80 to fly straight. VLD's do NOT have to be jammed into the lands to shoot either. Recent loading developments have proven that VLDs can be jumped condsiderable distance and still achieve sub moa accuracy.
I personally shoot a 90gr VLD from Swampys (formerly JLK) at 800, 900 and 1000yds. This loaded over a decent charge of REL15, LC brass (new) and CCI BR4 primers. This ammo will shoot better than I can hold - mechanical accuracy is probably a tad under 1 MOA - I can hold it at about 1.5 MOA. This load comes out of my primary rifle at 2620 fps w/ SD's in the single digits and ES at about 15fps (avg). (BTW - both rifles are M-16A2 type rifles - set up as NM High Power Competiton guns) The back up /practice rifle shoots the same load but with a different barrel - a 7 twist just like the GI barrels. Primary rifle has a 3 groove 6.5 twist tube on it. Interstingly enough - while both chambers were cut with a custom reamer - they both give the same OAL as a standard 556 NATO chamber/throat. The point of all this is that a pretty accurate load can be run through a standard barrel at 1K that exceeds the performance of any 80 SMK. Us weirdos, who compete at 1K can not afford misses - hell an 8 or even a 9 is a recipe for failure. As such, these rifles are capable of shooting a clean at 1000 yds w/ decent X counts (20rds) - the 10 ring is 20" and interestingly enough - an average man is 19" from mid shoulder to mid shoulder...
Bottom line here - I want to reiterate, no intent to steal your thunder, the point is; hats off to you for a very interesting and impresive test. As some others have written - trust the capabilities of the rifle - they are capable of FAR more than most believe. The NM rifles are not space machines - they have good triggers, very good free floated bbls and more precise GI sights - the inherent accuracy is there in the design.
The only caveat in all of this when the discussion turns to combat rifles and terminal performance - sure IF you hit someone at 1K w/ a 62gr FMJBT, it may hurt him, but when you are trying to perforate johnny jihad into submission - 1K is outside of the combat effective range, although it does send an impressive message.
Again - kudos - well done and sorry for the long post.
I'm more than skeptical of many long distance claims. Some which have received wide acceptance, by "snipers", were simply not mechanically possible with the optic rifle combos mentioned.
It has been a long time since I have used irons to any significant degree, had to chew on this a bit and recall the mechanical characteristics. If I recall, from many years ago shooting service match. A 3/6 "A4" type rear sight gets one around 15moa range of adjust on a fullsize m16A2 length sight radius. (Which is why we all had 3/8 "A2" sighted non-picatinny uppers to enable us to get to 600 with heavier match loads)
The shorter sight radius will give you a bit more elevation per click than the longer perhaps 10-15%.
A mechanically perfect carbine gives one 1.7moa per click on the front sight. However we need to lower the front sight to raise the POI. One can get up to 15 "up" clicks, meaning moving the front sight post downward into the recessed hole. Allowing for 25.5moa adjust with front sight fully compressed.
So 16.5moa rear and 25.5moa front sight fully depressed puts one on the theoretical edge of mechanical adjust for a 1000y 2925fps m855. It would seem odd, in an article, one wouldn't mention the non-standard extreme sight adjust. Off an AB app I show 43moa or so required for a M193 going at 3150, it would be quite challenging to holdover a target with a sight blade several times wider, covering it. But hey, it's an app and maybe garbage in.....
It would be more interesting to me to know the MV, sight adjust, and have a piece of cardboard/plywood behind target, to get a circular error of probability (CEP) results.
The shooter programs are pretty good. Im terrible at inputting data and still do well. If you chrono your load, and input bullet BC etc and it calculates true at 500 and 1,000. The app will tell you your velocity. Its gotta be damn close if it says 10 mils, and 10 mils rings the bell. It must know how fast its going. The app shows the velocity and shows when your go subsonic etc on most programs.
"Air Force / Policeman / Fireman / Man of God / Friend of mine / R.I.P. Steve Lamy"
Anytime you want to test some more loads, let us know. We loaded some XBR powder that shot very well. Also, if you get a Test crazy and want to run some 69 vs 77 test. Or test with SBR's......We will send you some to test. Mark is a sick sick reloading machine. His shit is so accurate. Its Breakin Bad gone Ammo!
We loaded another batch of XBR that was unusually hot even for XBR, primer popping hot. We only shoot it out of my bolt 5R, but it smokes 1k. If you have a bolt, let me know.
Have a good weekend fellas.
"Air Force / Policeman / Fireman / Man of God / Friend of mine / R.I.P. Steve Lamy"
alright
did some stuff at the range yesterday. I will be talking about it in more detail on the looserounds website but here is a picture of the target I shot at for you guys who wanted to see the 80 grain seirra HPBT in action
This was not shot with a A2 or M4 of course, I used a gun more suited to this type of thing. It was a perfect day with no wind at the time. I did string the shots and call me hits wrong. I also thought I had my hits more center on the target. I was hoping to have a great picture of hits in center masss haha. but.. Oh well. its still a good showing in my opinion.
i circled the hits in red some are in the chest area but the red marker doesnt show. You can still make them out I think. After getting on target with spotters. I fired 20 rounds. All but two made hits.
No I did not intend to shoot the targets nuts off.
I also managed to luck a few hits in with a 11.5 inch barrel Colt Commando after 90 rounds. I may show that later. I will at the very least link to it from here to the blog
Last edited by shawnmt6601; 09-30-13 at 13:59. Reason: more text
I agree with everything you said. I have been told for years in person and online that certain things can not do certain things at long range. especially when it comes to the AR15. even now Im sure people will ignore my telling them how I manipulated the front and rear sights to be able to get on target at 1K just to say it can't be done.
This thing started out for me back in 06 when I and some friends decided to make a 1 mile hit using a HS precision .338 Lap Mag and a Custom M700 in .300 Rem Ultra mag. I decided I wanted to make a hit at 100o with an AR15. I worked up loads and practiced in prone with a sling for 2 months. Every night dry firing in prone on the living room floor for 2 hours. I wanted to just use a sling and irons to make my hit.
it took a few tries to learn what it would take. So I ended up with the 80s and a Colt HBAR Match Target customized lightly. I was ablke to ring a gong the size of a mans chest from prone once and and again in setting position. It took a few rounds but I did it.
I was more proud of that then my 1 mile hit with a 338 lapua. It was a goal I set for myself and worked hard to achieve. I then when on to use a Target bolt gun in 556 with the larger bullets to do it fairly easy. But it was not the same. Then recently I came back to it to use a rack grade A2 to instill confidence in those who think the AR15 is a 20 yard gun. I was not the one to share it here. I had only talked about it on our website. I would like to remind people of the fact I did not come here posting it. I came to answer questions about it once I saw another person had found it on the blog and reposted it here.
I have not tried the VLD 90s. I will take your work on them. I could never get enough velocity out of the seirra 90s to make the perform better then the 80s in any meaningful way. I did this back a few years ago and tried it along with the data provided by Accuracy Speaks in their article on the 90s in Precision Shooting Magazine. I found there results to be the same. so i stopped fooling with them. Of ocurse things change in the reloading world fast these days. I would love to talk about it more with you though as well as some other things
I will IM you my email so check it if you have not seen it already.
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