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I just got my AR set up with a free floating hand guard and wanted to try to improve my groups with heavier bullets. I have a 1 in 7 twist and have a box of Hornady 75 hpbt and 80 grain amax. The OAL seems to be a limititing factor. I can feed them one at a time but what are people using for an overall length? MY rifle is a Sig M400 with a 16 inch barrel.

I have a small supply of Varget, 335 and 1/2 a pound of benchmark for my trials. What are you using out there? The goal would be a 300-500 yard shooting either deliberate or snap shooting. I might stretch these out to 600 yards.
 

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I think it was 2.49 was the max before you need to single hand load. Just make sure your bullet is seating either before or into the rifling and not just touching it can cause dangerous breech pressures. I have charts somewhere in my truck I will look for them after the Giants Cards game. There is a max number though where it will not magazine load anymore.
 

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K I remember it around 2 1/4 or 2 1/2 I had a printed sheet from when I took a 5 hr class on loading match grade .223 ammo from a 3 gun compettitor with the NYPD. It was an intense course and I learned a ton from my hilbilly reloading to match grade competition reloading. Thanks for the correction.
 

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Sticks and stones may break my bones but you'll not be biting my ankles. They had 3031 at the Cabelas grand opening so I grabbed up an 8 pounder. I've got carbines, middys and rifle length. Upon consideration the testing they did initially was a rifle length gas 20" barrel, yes? I got an Adams Arms piston kit for one of my rifle length but again considering whats posted here the carbine would benefit the most from that upgrade, no? Came with the bolt carrier. Midway had em on sale for like $158.

P.S. Thanks for the info guys.
 

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Just make sure that if the Bolt Carrier did not come with the barrel that the head spacing is good. Chances are it should be fine but if it is not an assembled upper it should be checked before firing.
 

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Just make sure that if the Bolt Carrier did not come with the barrel that the head spacing is good. Chances are it should be fine but if it is not an assembled upper it should be checked before firing.
And this requires removal of the ejector.

-Nate
 

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Magazine length is pretty much limited to 2.26"

Terry
And with most BTHP, you really need to be running the rounds through a caliper or other gauge if you intend to fire from the magazine with rounds longer than 2.255" COAL.

At least, if you care about jams.

-Nate
 

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It's not too bad, really. It CAN be done with skill and a fired casing. A third hand is handy as well.

I personally recommend a bolt vice like Sinclair makes. That, a tension-pin punch, and care is all that is required.

It should be a habit to replace the ejector spring with every barrel change. It should further be a habit, for the mil-spec spring, to carefully cut off two coils and file the bottom flat again. I also like to coat both ejector and ejector spring with ceramic anti-seize before installation.

-Nate
 

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Hey guys quick question, pretty sure I'm okay but want to check...

I need to load up some match HP rounds for shooting the local siloutte match. (missing tomorrow's event because I don't have the right ammo right now lol). I have a 20" 1:9 twist barrel on my AR. I should be okay using either the Horady 68 grain match or the 69 grain SMK, right?
 

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If it don't run right, check for the problem and fix it. You may have to open up the gas port, work with buffer spring tension, or modify the weight in the buffer, I guess you could stop picking your ears, but that never made my AR's run any better.. LOL
 

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So just FYI, the 68 grainers worked awesome in my rifle today.
 

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For my fellow Canadian's I have high praise for the Cam-Pro bullets 55 grainers are capable of MOA out of my AR15. I was able to pull that off with CFE and CCI Small RP over 3 groups of 5 I had .93, 1.05 and 1.03. Great bullet on the cheap.
 

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Couldn't read it all but main thing I got and think the main purpose here is to stress need to use the right powder. So I am going to pick up some Benchmark. Since the AR was originally designed for a lighter bullet and I plan to use a 77 gr Sierra HPBT and shoot it suppressed with a Heavy Buffer does that change anything in regards to powder?
 

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I've heard great things about RL15 in the AR15.
RL15 works very well for 62-77g bullets in my 20 inch heavy fluted barrel, with a 1-8 twist half inch groups at 100-500 yards, no gas issues, of course my rifle is very fine tuned, I use many different test powders my go to is RL15 for heavy bullets, and cfe223 (with magnum primers) reduced by 1.5 gr and it burns clean reliability is perfect.
 

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Now listen up and pay attention. I am about to share some extremely important imformation with you. This information is absolutely vital if you have an AR-15. Now pay close attention and don't ask me any stupid questions otherwise I may bite your ankles.

First of all the AR-15 was a fantastic rifle when originally designed by Mr. Stoner. All the problems along the way were cause by slack-jawed, dopey schmoes who monkeyed around with a great design. So listen to me and let me tell you how to deschmoe your AR-15.

The AR-15 was originally desgned around IMR-3031 powder. This was the propellant originally used by Bob Hutton, the guy who invented the .223. Mr. Hutton was a friend of Eugene Stoner and that's how Hutton got involved designing the round. Mr. Hutton was also the Handloading Editor of Guns & Ammo magazine.

Automatic weapons are resonant mechanisms and the AR-15 was tuned for IMR-3031. The IMR-3031 burn rate was used to calculate the mass of the bolt and carrier together with the mass of the buffer.

Original .223 ammo was loaed with IMR-4475 which was a mass-production version of IMR-3031. And when used with IMR-4475, the AR-15 was superbly reliable. In July 1962, the AR-15 was tested in Vietnam and 80,000 rounds were fired. Over the course of firing 80,000 rounds there were no parts breakeages. A report titled "Test of ArmaLite Rifle, AR-15" was published. The report concluded that the AR-15 was "the best all-round shoulder weapon in existence"

The rifle was perfect until a change was made in the AR-15's propellant. The powder was changed from IMR-4475 to a ball powder, WC-846. Now this ball powder ruined the rifle. WC-846 contained calcium carbonate which caused fouling in the AR-15's gas-tube. Even worse, this ball powder burned at a slower rate.

Using a slower burning powder in the AR-15 created the following serious problems:

1. A higher residual chamber pressure. This created a tendency for the fired cartridge to stick in the chamber;

2. The higher residual pressure causes higher bolt velocity. The bolt wants to unlock right NOW and when combined with a sticky case, the extractor can yank the rim right off the cartridge case. This can lead to the most disasterous jam possible. Higher bolt velocity also leads to increased wear and parts started to break. As a result, Mr. Stoner's wonder-weapon became a rotten piece of Clinton.

To solve the ball powder fiasco, the Army decided to treat the symptoms and not the desease. The army tried to slow down the bolt carrier by using a new, heavier buffer. The sticky chamber problem was solved by the use of chrome plating. But the Army continued to use slower-burning ball powders.

Now if you want to deschmoe your AR-15 and to enjoy original 1962 reliability, USE THE RIGHT POWDER. USE IMR-3031 OR BENCHMARK! Don't use ball powder and don't be a schmoe!!

Read the tacked thread about loading .223 ammunition and follow all the advice contained therein. If you use this information and load your ammo with the right powder, your rifle will perk nicely.

If you use a carbine version of the AR-15, make sure that you use the right buffer. If you are using a telestock, use a 9mm buffer. The 9mm buffer is slightly heavier than a rifle buffer. Use the 9mm buffer to slow down your bolt velocity. Or you can use a fixed rifle stock and buffer.


If you have an AR-15 carbine, install a Defender D-ring around your extractor. The AR-15 carbine has a higher gas-port pressure than Stoner originally intended. And the bolt velocity is higher too. With the higher bolt velocity, the extractor is stressed and you need stronger extractor tension in order to maintain reliability. AND USE THE RIGHT POWDER!!

The Defender D-Ring offers cheap insurance for AR-15 rifles too. And as you tune your load, check the extraction pattern of your rifle. Make sure that the rounds are extracted and ejected about 8 to 10 feet from your rifle. If you use Benchmark or IMR-3031 you will find that you can achieve a remarkeable uniform ejection pattern and all of your fired cases will land in one pile. This is a very good thing. Now go to the tacked "Loading .223 ammo" thread and read it carefully.

The Defender D-ring is available from Brownells. It costs $12.95

Check out Brownells - Firearms, Reloading Supplies, Gunsmithing Tools, Gun Parts and Accessories. The Defender D-Ring can be found as part no. 741-015-003.

(The Defender D-Ring was designed by Mack Gwinn and L. James Sullivan. Take note that Mr. Sullivan was the engineer who assisted Mr. Stoner in the original AR-15 design)

So don't be a schmoe. Just listen to me.

Fluffy.
This guy probably on to something, I was with Bravo co. 1/3 Marines. They had us changing out those dam buffer tubes every few weeks, a lot of stuck cases in the heat of battle. Vietnam 67-68
 
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