AR reloaders input please.

[Conte]

The only difference I've heard so far between reloading for an AR vs bolt action is apparently the throat in an AR is a bit longer so a cartridge fired in both will have less pressure in the AR.

This assumes it has a 5.56 chamber.
Use 223 load data and work up to a mid hot load. That's what worked the best with me.

I've loaded thousands with Lee Dies. Worked Great.

Powder selection is important. Some powders won't cycle as well as others. 4198 and 3031 give a great bang for buck in a carbine but don't work well in a rifle length gas system.

PRIMER SEATING IS PARAMOUNT. You want to make sure all your primers are correctly seated flush or below flush. This will eliminate the biggest safety issue that I'm aware of. I use a ram primer to make sure. "Sloppy primers make slam fires".

Depending on the cut of the chamber, Neck sizing can work really well. I've neck sized exclusively and it has caused no problems.
You MUST FL size, unknown brass. You MUST keep track of which brass came from which gun. Best to label your brass. I use a sharpie to tag a mark across the head so I know what brass I pickup at the range is mine that I fired out of that gun that day.
I don't recommend Neck sizing unless you're an experience reloader who can do certain chambering experiments safely to get a feel for how your Neck sized rounds will cycle. Basically, knowing the risks, and pre chambering sized brass to see how smoothly it'll seat into battery and knowing what to look for.

Crimping is optional provided you have proper neck tension to begin with.
I crimp FMJ plinking rounds. I don't crimp "presicion" rounds.

In short, lee works.

 

[stralia]

This assumes it has a 5.56 chamber.
Use 223 load data and work up to a mid hot load. That's what worked the best with me.

I've loaded thousands with Lee Dies. Worked Great.

Powder selection is important. Some powders won't cycle as well as others. 4198 and 3031 give a great bang for buck in a carbine but don't work well in a rifle length gas system.

PRIMER SEATING IS PARAMOUNT. You want to make sure all your primers are correctly seated flush or below flush. This will eliminate the biggest safety issue that I'm aware of. I use a ram primer to make sure. "Sloppy primers make slam fires".

Depending on the cut of the chamber, Neck sizing can work really well. I've neck sized exclusively and it has caused no problems.
You MUST FL size, unknown brass. You MUST keep track of which brass came from which gun. Best to label your brass. I use a sharpie to tag a mark across the head so I know what brass I pickup at the range is mine that I fired out of that gun that day.
I don't recommend Neck sizing unless you're an experience reloader who can do certain chambering experiments safely to get a feel for how your Neck sized rounds will cycle. Basically, knowing the risks, and pre chambering sized brass to see how smoothly it'll seat into battery and knowing what to look for.

Crimping is optional provided you have proper neck tension to begin with.
I crimp FMJ plinking rounds. I don't crimp "presicion" rounds.

In short, lee works.

I will be using AE box ammo for range plinking but reloading for my precision rounds also. Is there any reason to, or not to crimp for the precision rounds? This particular build has a RRA 16" match barrel and I will be shooting out to 200 yards. I reload for other target guns I own including .223 but haven't started load development as yet for the AR so any input on the precision side would be appreciated.

 

[ffgats]

The Genenral Rule- Bullets with Cannelure= Crimp, No Cann=No Crimp
Sometimes the Crimp will add more of the Variables, A good Neck Tension is enoughh to hold the bullet- in this case 223 rem ( .224) usually needs .002-.004 Neck inside diameter, so thats.222-.200 I.D.
Check your expander( found on the decapping pin of your sizing die) if you have the correct size.
I full resized all my brass since I pick some range brass too, no time to sort, After many firings, your brass eventually will have to go to Full resizing anyways. Its true that full lenght resizing shortens brass life, but seriously if your shooting your AR in a CQB or 3Gun, what are the chances of retrieving 100% of your brass.

 

[TRG-42]

I will be using AE box ammo for range plinking but reloading for my precision rounds also. Is there any reason to, or not to crimp for the precision rounds? This particular build has a RRA 16" match barrel and I will be shooting out to 200 yards. I reload for other target guns I own including .223 but haven't started load development as yet for the AR so any input on the precision side would be appreciated.

First off ,if you are loading precision loads vs plinkers you are probably shooting 69Gr , 77Gr Sierra Match King , 75gr A-Max , one of the many Bergers etc . None of these bullets have a cannuler for crimping

The only exception to this is the SMK 77Gr used in the military MK262 Mod 1 loading but as far as I know you can't buy this projectile

Although the Lee Factory crimp die claims you can crimp on a non cannuler bullet why in the world would you take a precision made target bullet and deform it with a crimp

Keep in mind that one of the more common go to powders such as Varget for these heavy weight 5.56 loads , combined with the long length ( especially the A-Max ! ) leaves zero room in case anyways . Even if you had crappy neck tension I find it hard to believe you could actually push bullet in further

You will develop feel for how much neck tension there is when you seat the bullet. If case has thinner neck, it will have less neck tension, since the neck portion of your die is fixed. That is the advantage of bushing dies...you can control that buy choosing how much you want to squeeze the neck down

BTW : the reason the Lee factory crimp is best method if you need to crimp is that it crimps via a collet that is closed by the shell holder. Therefore it crimps regardless of variation in COL length. This is unlike a standard seating die that has roll crimp built in. The shorter the case , the less it crimps

As far as FL vs Neck , I never FL for any bolt gun since all brass stays with the one gun

I often FL my 5.56 I do since I have numerous 5.56 AR uppers . I only Neck size on my 6.5Grendel

I only neck size virgin 223 brass ( no need to FL size ) but I neck size to ensure proper neck tension ( using Redding bushing dies so I can control that )

I freaking hate cleaning lubed cases , which you need to do with FL . For neck sizing I use the Redding dry graphite neck lube

 

[stralia]

First off ,if you are loading precision loads vs plinkers you are probably shooting 69Gr , 77Gr Sierra Match King , 75gr A-Max , one of the many Bergers etc . None of these bullets have a cannuler for crimping

The only exception to this is the SMK 77Gr used in the military MK262 Mod 1 loading but as far as I know you can't buy this projectile

Although the Lee Factory crimp die claims you can crimp on a non cannuler bullet why in the world would you take a precision made target bullet and deform it with a crimp

Keep in mind that one of the more common go to powders such as Varget for these heavy weight 5.56 loads , combined with the long length ( especially the A-Max ! ) leaves zero room in case anyways . Even if you had crappy neck tension I find it hard to believe you could actually push bullet in further

You will develop feel for how much neck tension there is when you seat the bullet. If case has thinner neck, it will have less neck tension, since the neck portion of your die is fixed. That is the advantage of bushing dies...you can control that buy choosing how much you want to squeeze the neck down

BTW : the reason the Lee factory crimp is best method if you need to crimp is that it crimps via a collet that is closed by the shell holder. Therefore it crimps regardless of variation in COL length. This is unlike a standard seating die that has roll crimp built in. The shorter the case , the less it crimps

As far as FL vs Neck , I never FL for any bolt gun since all brass stays with the one gun

I often FL my 5.56 I do since I have numerous 5.56 AR uppers . I only Neck size on my 6.5Grendel

I only neck size virgin 223 brass ( no need to FL size ) but I neck size to ensure proper neck tension ( using Redding bushing dies so I can control that )

I freaking hate cleaning lubed cases , which you need to do with FL . For neck sizing I use the Redding dry graphite neck lube

Great information thank you. I will be loading 69gr SMK with Varget, is there any point in trying a 55gr Vmax for instance, or is that more for plinking purposes rather precision?