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Old February 22, 2010, 09:59 PM   #1
Lavid2002
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Reloading for accuracy....Ar15 reloads cant hit the lands?

So in my savage .308 I just draw sharpie all over a bullet, seat it a little bit in a casing. Then close the bolt on the round and the lands push the bullet into the casing. I measure it and I know my COAL where the bullet is touching the lands. I can use this infor to back off .005" and find that 'Sweet Spot"

However....I tried this on my AR15 and even with the bullet BARELY seated....I cant find the lands : |

Bullet comes out exactly the same as when it went in.

Is this a common issue. Do 5.56 chambers have a very large neck area in between the second shoulder and where the rifling lands start? Because I cant find those motha's....
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Old February 22, 2010, 11:01 PM   #2
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Pretty normal but it all depends on what bullet you are using, the condition of the throat, and the particular chamber dimensions.

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Old February 22, 2010, 11:07 PM   #3
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Are you loading to magazine length?
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Old February 22, 2010, 11:33 PM   #4
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Since I cant reach the lands with 55 grainers I will be loading to mag length. I made 4 bathes
2.280
2.270
2.260
2.250

well see what my rifle likes best tomorrow : )
Im trying to find a good load for her : P
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Old February 22, 2010, 11:36 PM   #5
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556 chambers will have a bit of a longer throat on them than 223 chambers.

I think you will be outside of mag length before you ever get to the lands in a 556 chamber. Unless you are using 80 or 90gr bullets.

I highly doubt a 55gr bullet will hit the lands in an ar556 chamber.
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Old February 22, 2010, 11:40 PM   #6
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Weve been over that remember I couldnt hit it?
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Old February 22, 2010, 11:42 PM   #7
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Try again with some 68 or 69 gr HPBT pills.

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Old February 23, 2010, 12:06 AM   #8
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I remember I could hit them with some 75 grainers I did a long time ago in spring 2009. But they shot terrible.... I want to make a decent load for these bullets because I have 2,000 of them : )
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Old February 23, 2010, 11:27 PM   #9
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I have seated 75 gr bullets at the tip of the 223 case mouth and still could not reach the lands in my Bushmaster V-match.
That cartridge is WAY too long to fit in the magazine.
What were they smoking when they came up with the 5.56 throat lengths?

My Ruger #1V cost half of what some of my AR15s cost.
The AR15s shoot 1" and the Ruger shoots 0.5" with the bullets jammed into the lands.

I ordered a custom 223 Rem reamer with .250" neck and .050" shorter throat.
I have yet to put a barrel on an AR15. Maybe this year.
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Old February 24, 2010, 01:38 AM   #10
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Quote:
Ar15 reloads cant hit the lands

OH yes they can, I figured this out the hard way.

I've been shooting M14/M1As in High power for about 30 years so I desided to evolve with other high power shooters.

I got a White Oak, loaded my 77 gr SMKs so they fit the mag, and knew I didnt need my 80s for 600 to fit the mag so I loaded them long, per the book, 2.550 COL, but since I was a 'KNOW IT ALL" I didnt try them before I went to my first match using the AR.

I'm on the 600 yard line, and after my first two record shots, I chambered the round, then noticed a boil, so I pull the case out, not wanted in to set in a hot chamber waiting for the right condition. My 80 bullet did reach the land........ AND STAYED THERE, I dumped powder in my action. I didnt have a cleaning rod and couldnt get to one., never needed one on the line with my M1a..........I had to wait for a pit change.

I found out that the 223 will touch the lands, and a total of 18 pts on the 600 yard stage dosnt do much for your total score.
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Old February 24, 2010, 04:01 AM   #11
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whoops

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Old February 24, 2010, 04:02 AM   #12
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If you rub Magic marker all over a bullet and jam it into the lands, the rifling marks can be plainly seen.

I have never been able to get those marks with a 75 gr bullet.

Maybe with a loose neck to bullet fit, I could slam the bolt forward so fast the bullet left the case mouth and went way down the barrel and found the lands. Then it could get marks.
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Old February 24, 2010, 11:26 AM   #13
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funny. I just loaded up some rounds.
10 rounds each
seated to these lengths
2.28
2.27
2.26
2.25
Guess what performed the best with surplus 55 GR bullets?
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2.26 and 2.25 !
Funny B/C My savage likes em at the lands. Im gunna load of 50 of each and do some more intensive tests
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Old February 24, 2010, 12:03 PM   #14
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Lavid2002,

I don't know anything about your AR. If is has a NATO chamber, the freebore to the rifling will be 0.050" where a .223 Remington chamber has 0.020" freebore (those are Clymer's specs, anyway). The military created that spec to accommodate special purpose rounds that have blunt bullet shapes. Blunt bullet shapes have short ogives, so that even at normal magazine seating depths they can run onto the lands of a commercial chamber.

I don't know the rifling twist of your barrel? The guys talking about the long match bullets have 7" to 8" twist barrels, typically. If yours isn't that fast, you'll have trouble getting accuracy from those long match bullet designs, as you seem to have discovered on your own?

You can get a match upper that has a civilian (.223) match chamber on a faster twist barrel if you want to shoot the longer, higher BC match bullets? Military ball and standard shaped ammo will still work in such a gun just fine because, despite small differences in the NATO chambers, new cases for 5.56x45 are made to the same outside dimensions as civilian .223 Rem, just as is done with .308 and 7.62x51. Frank White said the upper on my Compass Lake match AR is built this way. Just don't expect all military specialty ammo will necessarily go through it.

Finally, it is not religiously true that seating close to the lands produces best accuracy. As you are discovering, multiple sweet spots for seating can occur. Walt Berger says specifically that his VLD shapes do not work as well up close to the lands as they do with some distance off them. Since backing a bullet off the lands allows a certain amount of gas bypass around the bullet, I have a suspicion there may be a kind of gas-bearing affect helping center the bullet, and that each chamber and ogive shape will center the bullet better on that gas cushion depending on a number of variables, distance off the lands being a big one. It's not a proven theory; just speculation.

The bottom line is, you can't really predict the best seating depth in advance of trying it out in your chamber with your bullets. If the gas-bearing idea turns out to have any merit, seating depth will probably have to be tuned with different powder and primer combinations as well. Just something to try.
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Old February 24, 2010, 02:15 PM   #15
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Interesting...Ill keep working on the load : )
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Old February 24, 2010, 04:15 PM   #16
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Quote:
Walt Berger says specifically that his VLD shapes do not work as well up close to the lands as they do with some distance off them.
The Midway product description still says this...

Quote:
Please note that the bullet should be touching the rifling when loaded and won't work in most magazines. This is not loaded ammunition.
It appears that Midway needs to update their product descriptions....
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Old February 24, 2010, 04:26 PM   #17
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Its very rare for it to TOUCH the rifling...that can lead to functioning problems. Lymans 48th recommends seating to the lands, minus 5 thousands as the longest.... Im not 100% on that one but thats what I remember reading...
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Old February 24, 2010, 04:48 PM   #18
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I can't imagine all the fuss. It's the man behind the rifle more than the ammo. I can routinely score 190+ from the 600 yard line and never even worry about any of this. I load my 77gr SMK out to 2.255" and have at it. All this 0.005" off the lands business....in an AR-15????? Come on now!!!!!!
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Old February 24, 2010, 05:02 PM   #19
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This has got changed in the literature over time. If you followed the link to Walt Berger's letter, you'll note it took some time and customer feedback for him to work out that the VLDs shouldn't be too near the lands. Midway apparently hasn't updated that.

Touching the lands is fine, pressure-wise, if you work your load up for that. There are some bullets that seem to prefer it. Lead bullets in self-loading handguns often shoot more accurately and foul less if loaded that way. Middleton Tompkins uses soft-seating. This is where the neck is sized so the bullet has just a little neck friction and you can still move it with your fingers. The bullet is seated way out, and seating is completed by contact with the throat when he closes the bolt. He loads for himself and his whole family of national and international match winners, so, obviously that's done well for them. The main drawback is that if a cease-fire is called when a round is chambered, you have to go muzzle up and open the bolt slowly, because the bullet will stick in the lands and you will dump powder into your action if you try to extract the round horizontally. A cleaning rod then has to be used to push the bullet out before loading and shooting resumes.

A lot of benchrest shooters also used to touch the lands, but most found it was not as accurate as seating some distance back. Mind you, benchrest makes a higher accuracy demand than long range position shooting does.

In The Precision Shooting Reloading Guide, one of the benchrest authors described how he'd one day turned the micrometer head on his seating die the wrong way and wound up with bullets 0.050" off the lands, when he'd intended to get 0.020" off the lands. He'd loaded 50 rounds before he noticed. He debated trying to fix them or just shooting them in practice, and decided on the latter. To his surprise, they shot better than anything he'd ever loaded for that gun before.

Isn't it interesting that people as involved with precision loads as a benchrest shooter or a match bullet maker wouldn't have done the early testing needed to learn what seating depths worked best for them, and have to find it out from accidents or from customer feedback that puts them on the right testing track? I think we all get caught up in conventional wisdom from time to time, and certain seating distances off the lands have have some dogmatic adherents. I've heard people say it's "always best to be 0.005" off, or 0.010" off, or 0.015" off, or 0.020" off, or 0.030" off, or . . ." You get the idea. Keep an open mind. Try things.
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Old February 24, 2010, 06:23 PM   #20
Lavid2002
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Quote:
I can't imagine all the fuss. It's the man behind the rifle more than the ammo. I can routinely score 190+ from the 600 yard line and never even worry about any of this. I load my 77gr SMK out to 2.255" and have at it. All this 0.005" off the lands business....in an AR-15????? Come on now!!!!!!
I never said seat them .005 off the lands in an AR15. I just said the reloading manual I have says that is the max for rifles...

For the "Does it make a difference" part.... Sure...At least it has for me in the past. It also did on tuesday when I did my testing
Heres the groups from tuesday when I went shooting.
All numbers are in inches
COAL-Target grouping @ 100 yards
2.280-6 3/4
2.270-6
2.260-4
2.250-3 3/4


Seems to make a difference for me : ) I need to make more loads and do more testing for more consistent data though. These are 10 shot groups. I want to increase the sample size.
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Old February 24, 2010, 08:21 PM   #21
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Lavid2002

Those are not good results, I had a 1968 Armlite AR-15 that would shoot less than 2 inch groups with Milsup ammo. My Bushmaster Varminter does .40 MOA with 53 and 55 grain bullets.

What are you shooting? And who's bullet are you using (2000??? varmint gernades??)

Better bullets make better groups. You do get what you pay for.

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Old February 25, 2010, 12:03 AM   #22
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I know there not good results. The bullets cost .07 a piece ! I have vmax and nosler. They group up well. But these are suplus cheapskie bullets and im trying to make a 16 cent load as accurate as possible :P
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Old February 25, 2010, 12:04 AM   #23
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I have been working up 600 yard loads for my Match Service Rifle, new to High Power & loading for match 223. Just a couple of things I have been doing, have 25+ years of loading, so have some experience, and have several books on this subject.

I want to go back to the guy who learned the hard way, we all make mistakes and sharing them are helpful for others. I was at the 600 line with my M1A and a guy was having problems grouping his rounds, light stuff like 55-60 grain. This was the live fire required for new shooters beyond 300 yards. Some other guy offered his ammo to help this guy out; he loaded some and lent the bolt slam forward. He was done, jammed the bullet in the rifling took time and a few guys to get it clear.

I use the Hornady OAL gauge and you use it in the gun you are loading for, it has a case and you sit a bullet in then once set in the chamber, push it forward. It will stop when it hits the lands. I do it several times to be sure and then know the Max OAL for that bullet and rifle. I then back them off about 10 thousands. The 77 Nosler fit in the magazine, I know this can be a problem especially with the 80s.

Not to start the Molly debate, I do molly some bullets and like the stuff it has its good and bad. I do not claim this from my loading but have seen in several books that molly bullets can touch the lands for best accuracy. I have backed them off a hair and they shot well.
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Old February 25, 2010, 01:41 AM   #24
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88 keys.... 2 things

1)55-60 GRAINS in a .308 M1A? Really? 55 grain .308 bullets?

2) Do you have a .223 chamber or 5.56? My problem isnt hitting the lands....its the lack thereof
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Old February 25, 2010, 03:15 AM   #25
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For info only: Hornady 55 FMJ's seated to just touch the lands of a Rock River and Colt AR 15 standard nato chamber:
Overall Length
-RR--2.370"
-Colt--2.390"
-Bolt Action Remington XP100R---2.246"
-WOA upper, Wylde chamber
80 gr Sierra BTHP to lands 2.472" oal
77 fr Sierra BTHP to lands 2.316" oal
Loading 55 fmj's to get near the lands is not possible in standard AR chambers. Load to recommended oal by the bullet manufacturer is recommended and trying to seat them longer in my experience provides no increase in accuracy. 77 gr. Sierra BTHP's are designed to be loaded to magazine lengths of 2.260" or a little less. 80 gr. Sierra BTHP's which are loaded directly into the chamber and won't fit your magazine are reported to do best seated 10-15 thousandths off the lands. YOUR RIFLES CHAMBER MAY BE DIFFERENT and these are just numbers from mine and for info only.
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