556 sizing problems

[Striker9]

I have an Anderson Mfg. AR15, and they indicated it IS chambered for 5.56. I resized on 550b using Dillion dies but they don't chamber properly and get stuck. Not sure what I'm doing wrong. I'm feeling like the shoulders aren't getting size/pushed back far enough because I've measured everything else compared to .223 and I can't find any major differences. I just don't have a way to measure the shoulders angle. They fit fine in case gage. I've tried taking the size die all the way down to shellplate but i know that's not proper setup or the way to go so put it back to recommended specs. If anybody has had this problem or knows how i can fix, please help. I have a lot of 5.56 brass and would like to be able to use it. I'm a newbie so please keep words to five letters or less. ;-)

[Mad River Arms]

Dillon says to screw the sizing die down to the shell plate, back it off a half turn, size a case, measure it with a case gauge and adjust from there. I take that to mean up or down to get the case headspaced correctly.

I have my die all the way down to the shell plate and with commercial brass it headspaces correctly in the Dillon case gauge and is trimmed to the correct length with the RT 1200B. However I have found that LC cases are not getting sized the same and are still a little long with respect to headspace but are getting trimmed to the correct OAL. I haven't figured that one out yet.

-MRA

[RiggerJJ]

LC is harder, takes more ummpf to size.

OP, are you trimming the brass to spec length as well? (if not, the neck could be too long), you MUST trim most of the time...

Don't forget, you MUST use case lube when full length sizing bottle neck cases...

Take your size die down to the shellplate, lift the ram, and screw it DOWN 1/4-1/2 a turn further(called over-camming). Then try a case in your chamber, I'll bet it fits... (further than 1/2 turn will damgage things like the shellplate)

If it doesn't, then you may have to use 2 sizing dies...one full length die, and then a BODY die to bump the shoulder down a bit more. I have one chamber that I have to do this with...

jj

[Mad River Arms]

LC is harder, takes more ummpf to size.

Take your size die down to the shellplate, lift the ram, and screw it DOWN 1/4-1/2 a turn further(called over-camming). Then try a case in your chamber, I'll bet it fits... (further than 1/2 turn will damgage things like the shellplate)

If it doesn't, then you may have to use 2 sizing dies...one full length die, and then a BODY die to bump the shoulder down a bit more. I have one chamber that I have to do this with...

jj

Duly noted re LC brass. Any references on over-camming?

-MRA

[Jaxshooter]

I use a Redding Small Base resizing die and have eliminated the problem you are having completely.

[427Cobra]

Get a small base die, use a Headspace Gauge to set up FL dies, IMHO the instructions that most FL dies come with are only good for toilet paper.

http://www.cabelas.com/product/Shooting/Reloading/Tools-Accessories|/pc/104792580/c/104761080/sc/104635080/Hornady-Lock-N-Load-Headspace-Gauge/740263.uts?destination=%2Fcatalog%2Fbrowse%2Fshooting-reloading-tools-accessories%2Fhornady%2F_%2FN-1100198%2B1000003666%2FNe-1000003666%2FNs-CATEGORY_SEQ_104635080%3FWTz_l%3DUnknown%253Bcat104792580%253Bcat104761080%26WTz_st%3DGuidedNav%26WTz_stype%3DGNU&WTz_l=Unknown%3Bcat104792580%3Bcat104761080%3Bcat104635080

[ajg308]

The 550 shellplate has a little spring to it. The directions say to screw it down til it touches then back it off. With the spring in the shell plate it mind I always go til it touches and then screw it IN a half turn. Works for my, YMMV.

[Striker9]

Small base die, i was wondering if that would do the trick. I will get one, hopefully local shop has them, if not there is a big gun show this weekend and maybe can find one there. I was think about the RCBS Precision Mic too. Thanks for the input all. Fortunately i have a couple extra toolheads i can use as additional prep for the 2000+ pieces i'll need to take the shoulders down on. It seems that is the problem becasue they are sized, proper length, etc. They just get stuck in the chamber and won't extract properly. I did try the different shellplate/die adjustments and just don't feel like that is the issue. And I basically have the FL die down to the shellplate. Not willing to take it lower for fear of bending it, then i'll have a whole host of other problems.

[benos]

Take your size die down to the shellplate, lift the ram, and screw it DOWN 1/4-1/2 a turn further(called over-camming). Then try a case in your chamber, I'll bet it fits... (further than 1/2 turn will damgage things like the shellplate)

The 550 shellplate has a little spring to it. The directions say to screw it down til it touches then back it off. With the spring in the shell plate it mind I always go til it touches and then screw it IN a half turn. Works for my, YMMV.

From talking with lots of customers on the phone, I've heard that's the ticket.

be

[g56]

I'm getting to around 10,000 rounds of 223/5.56 loaded on a Dillon RL550 using standard Dillon dies, absolutely no problems at all using the Dillon dies. If you are using Dillon dies, small base dies just aren't necessary. I run all my cases through my Giraud trimmer every time after sizing, it takes less time to run them through the Giraud than it does to measure them.

All my loads are run through AR15's, I don't own a 223 bolt action at all.

Edited June 23, 2011 by g56

[Striker9]

From talking with lots of customers on the phone, I've heard that's the ticket.

be

Thank you very much for the input and suggestions. I will try this again. Just on a visual check the shoulders look slightly different to my commersh 223. The cases I've tried to load are trimmed so I've eliminated that as a variable. I just don't know. g56 indicates he's had no problems with Dillon dies but it may not hurt to try small base or body die, they don't cost that much. I have another press and extra toolheads i can try it on. I'm going to narrow it down and figure it out. And will let you all know.

[Spanners]

I had issues with my RCBS(or Redding?) dies and changed back to an old Lee - job fixed.

Wasnt touching the shoulder when used in the Dillons - no good chambering in BA also - but in a single stage with shellholder was fine.

[Striker9]

Thanks Spanners, i'll keep that in mind. I keep my partner press nearby if i need to do some dirty work.

I do have a question for the salty dogs. Once the shoulders are pushed back, is that going to be a reoccuring issue for those 5.56 cases? I.e. will I have to size them again? I've had no problems reloading my commercial brass. Thanks.

[Joe139]

I had the same problem loading with a 1050 with a Redding die.First you need a Dillon case checker to make sure you don't under size them.It is a go no go type gauge you drop them in it and it can not stick out past the base of the gauge or go down past the groove cut in it.My die was not screwing down far enough it hit the base.That was my die I ended up putting it in a lathe and taking about .005 off of it.Them I screwed it down about .003 or 1/4 turn or so farther down and then that little bit sized it down enough to chamber.So if you turn your die down a little more which you said you backed it off the 1/2 turn maybe turn it a 1/4 turn it may be just enough to chamber but be carful not to under size it.That was just how I handled my problem.I would get a case checker to be sure since then I have a case checker for everything I load.

[benos]

Thanks Spanners, i'll keep that in mind. I keep my partner press nearby if i need to do some dirty work.

I do have a question for the salty dogs. Once the shoulders are pushed back, is that going to be a reoccuring issue for those 5.56 cases? I.e. will I have to size them again? I've had no problems reloading my commercial brass. Thanks.

Once you shoot any rounds with pushed back shoulders, then just resize them with a properly adjusted sizing die and you'll be all set.

be

[Striker9]

Hey, I'm pleased to report that the Redding Small Base Body die worked! It appears to have left a shiney ring all the way down by the base. My other FL size die was not doing that. Then, I made several dummies and they chambered and extracted perfect! I'm jazzed. Except, now...i have to process 2000+ pieces ....again....

Thank you all for the input and suggestions.

[ItsanSKS]

I had the exact same problem when I first started loading for 5.56. Cartridges made to pass the case gauge still wouldn't chamber in the rifle. Bought the above-referenced RCBS Precision Mic setup, and VIOLA! Problem solved.

When using the precision mic, you first fire a factory round (I use a group of 5) then measure the 'headspace' using the precision mic. I take an average over 5 rounds, as there is some variance. When setting up your sizing die, adjust the die depth so that you are sizing the brass to .001 - .002" smaller than the fired casing. IE: Fired case(s) measure .005" on the precision mic, set the sizing die to size the cases to .003 - .004" Before starting full production runs, always verify that the finished product will chamber in the rifle. (remove the firing pin for this test, to eliminate the possibility of a slam-fire)

I *used* to have the RCBS X-Die, which is also a small-base sizing die. I found that the upper die half was pretty weak, and I would end up replacing it nearly every 2-3000 rounds. On a 650xl, that can mean that a weekend's worth of reloading just got stopped, because of a weak die. Bought the Redding NM Competition die set, and haven't looked back. The micrometer bullet seating die is worth its weight in gold, especially for anyone who changes bullet profiles/weights within the same caliber. (I load 55, 62, 69 and 77 for 5.56, and all I have to do is rotate the bullet seating stem to the appropriate number, which I've notated, and change the powder drop)

[Striker9]

I had the exact same problem when I first started loading for 5.56. Cartridges made to pass the case gauge still wouldn't chamber in the rifle. Bought the above-referenced RCBS Precision Mic setup, and VIOLA! Problem solved.

When using the precision mic, you first fire a factory round (I use a group of 5) then measure the 'headspace' using the precision mic. I take an average over 5 rounds, as there is some variance. When setting up your sizing die, adjust the die depth so that you are sizing the brass to .001 - .002" smaller than the fired casing. IE: Fired case(s) measure .005" on the precision mic, set the sizing die to size the cases to .003 - .004" Before starting full production runs, always verify that the finished product will chamber in the rifle. (remove the firing pin for this test, to eliminate the possibility of a slam-fire)

Ya know....that would be great if I knew how to use the darn thing. I have one but the instructions didn't help this newbie very much. Not sure if I'm reading the tick lines on the headspace nut or the body. And I'm not sure on how to get my dies to correct measurement per the mic instructions. I currently have them set up per the die instructions. Almost thinking I should just call a gunsmith and have him show me how to use it. I am self taught reloader and don't know others except here on these boards.