brass sizing for AR15

[rcoodyar15]

Ok this is probably a dumb question. I have always full length resized my brass for my AR's. I have very good luck with accuracy in my bolt gun neck sizing only.

anybody out there just neck sizing brass for their AR?

How about you guys that shoot high power and single load bergers

[Ryno12]

I briefly experimented with neck sizing only on ARs when I first started reloading. Huge feeding and ejection issues. I had to mortar the majority of cases out of the chamber.
I quickly gave up on that & went back to full case sizing.

[HKGuns]

FL sizing only for my AR reloads. Too many issues to do otherwise.

[Koshinn]

For semi-autos (and full-autos I guess), full length size for sure.

[rcoodyar15]

What a shame but that is what I figured.

I wonder if anyone makes a body die that doesn't resize the neck

then you could at least use a neck sizing die.

I don't want to take the expander ball out of my die because it still will size the neck but much too small. Then you have to use an expander mandrill to open it back up. Kind of defeats the purpose of not overworking the brass.

I want to keep the runout down on my precision loads. My forster resizing die does a good job but neck sizing on my bolt guns is better.

[Koshinn]

What a shame but that is what I figured.

I wonder if anyone makes a body die that doesn't resize the neck

then you could at least use a neck sizing die.

I don't want to take the expander ball out of my die because it still will size the neck but much too small. Then you have to use an expander mandrill to open it back up. Kind of defeats the purpose of not overworking the brass.

I want to keep the runout down on my precision loads. My forster resizing die does a good job but neck sizing on my bolt guns is better.

I don't get the point of a body die that doesn't resize the neck?

[CrazyIrishman]

Redding makes a body die for the 223 that sizes the case body obviously, but also bumps the shoulder fyi. For my ARs I just full length resize with my Forster, but I have experimented with the body die and neck sizing for a few of the ARs. In my opinion it seem like just another way to skin a cat, group sizes didn't shrink, and its more or a pain to get set up and more work in the end and runout was SLIGHTLY less, like half a thousandth, roughly. I just use the neck sizing setup for my bolt guns, that's what I bought it for to begin with. the above was just one of those ideas that pops into your head at the reloading bench thats worth at least trying in the pursuit of tiny groups

[bp7178]

Being that this is posted in the precision rifle board, I would assume you are going for maximum accuracy.

The way to do this with a gas gun is to bump size. Smashing all your brass down in a FL die isn't going to get it. Using once fired factory new brass, fired in the rifle you intend to size for...clean it and gauge it with a RCBS mic. Set your FL die so it barely touches the shell holder. Run the brass through it, and re-measure. You're looking for a .003 reduction when measure with the RCBS mic. Adjust the FL die a bit lower and run it through again. Keep doing this until you get that .003 reduction. This is how you obtain perfectly sized brass that will function perfectly well in your rifle.

The only issues are if you're reloading for many different rifles, which have chambers in which the headspace is less than the rifle you sized for, well greater than .003 less anyway.

The goal here is to reduce the amount the brass has to expand to seal to the chamber when firing. When you examine your fired brass, you should not have any soot below the neck, or at least a minimal amount from the residual carbon left in the chamber after extraction.

[boombotz401]

I've found for an AR type platform the most important thing is consistency

Use a concentric tool

Use the same brass stamp once fired from your rifle

Hand seat the primers

I've found better accuracy without crimp

As for FL sizing using fire formed brass from your rifle .. .001-.003 should eject fine


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[Kansaswoodguy]

I played around with it some in a tight spec chambered Kreiger barrel but finally gave up and went back to FL resizing

[NuJudge]

Most bolt actions have a very gradual initial extraction feature, which is accompanied by a very gradual final breech closing, and the firing pin is strictly held to the rear during breech closing. None of that is present in most AR rifles.

There are lots of websites on the net that show blown up rifles caused by insufficiently sized cases in the AR.
http://www.fulton-armory.com/faqs/AR-FAQs/ReloadingThoughts.htm

[rcoodyar15]

I've found for an AR type platform the most important thing is consistency

Use a concentric tool

Use the same brass stamp once fired from your rifle

Hand seat the primers

I've found better accuracy without crimp

As for FL sizing using fire formed brass from your rifle .. .001-.003 should eject fine


Sent from my iPhone using Tapatalk

Well I like to experiment.

I tried the body die and neck sizing with a lee collet neck sizer. Not really any better than my forster die set

Now I am trying a new experiment. I bought a set of redding S full length sizing dies and a Wilson bullet seater. Really put this together for my portable reloading kit. Got me a Harrell combo press and a Harrell premium BR powder measure. Now I can reload anywhere.

yep I have found that a 0.003 shoulder bump work good.

[KUSA]

I've found better accuracy without crimp


I've had a bullet pushed back into the case before. I always crimp now. It may or may not effect accuracy but I sleep better at night now.