It appears I need a small base sizing die.

[Jay24bal]

I built my third AR15 this winter, and took it to the range today for the first firing. As I always do with a new gun, I started with factory ammo to ensure that it functions as it should, and no problem, 100 rounds without a single hiccup. I was actually quite impressed with the gun as this was a "budget build," but it was flawless and held decent groups.

Then, I load up some of my handloads. Not a single one works. I made the rounds using the same die set-up I have always used for my AR fodder (about 3,400 rounds). At first, they seemed to be fine and seemed to chamber, but when I pulled the trigger, all I got was a click. There was no dent on the primer either. It was also more difficult than it should be to extract the round from the chamber. I then followed up with more factory ammo to ensure something did not get damaged in the interim, and it was back to flawless operation.

I have no experience with small base sizer dies, and this is the first time I have encountered this problem. Am I correct in assuming that the chamber is a tad tight and that a small base sizing die will help?

 

[F. Guffey]

It was also more difficult than it should be to extract the round from the chamber. I then followed up with more factory ammo to ensure something did not get damaged in the interim, and it was back to flawless operation.

After 3 builds and all that reloading seems comparing new factory ammo with sized ammo would be first on the list of trouble shooting. We know what rifle you are using, it would be nice to know what press.

Then there is 'mastery of the press' if my cases are not being chambered I want to know if the case is being sized, your cases could be whipping the press.

I would not assume the case is difficult to extract after pulling the trigger, the cases could be difficult to extract because of the bolt closing.

By all means purchase a small base die, I have a few, I do not need them but, I have them JIC.

F. Guffey

 

[chris in va]

I don't pretend to know a lot about AR building, but is it possible the barrel has a head spacing issue, maybe not screwed in enough?

 

[F. Guffey]

As I always do with a new gun, I started with factory ammo to ensure that it functions as it should, and no problem, 100 rounds without a single hiccup. I was actually quite impressed with the gun as this was a "budget build," but it was flawless and held decent groups.

Then, I load up some of my handloads. Not a single one works.

I would suggest he try sizing the 100 once fired cases he started with instead of the cases from his 3.400 pound stash, there is no telling how many times those cases have been fired.

then there is the press, no one knows the ability of the press to overcome resistance presented by the case, meaning the case can have more resistance to sizing than the press can overcome. There are fundamental skills that can be practiced by a reloader, but, that would require a feeler gage.

F. Guffey

 

[wwmkwood]

Welcome to the club. There are some tight chambered uppers out there that no mater what your head space may be "need" a small base die.

 

[mehavey]

Small base aside, are you sure the cases were effectively resized
to SAAMI minimums and not left slightly long due to case and/or
press springback?

(And if you believe you're sure, why do you think so?)

 

[A pause for the COZ]

Welcome to my world.
My 223 is the only gun that I have ever even had a problem with.

Still not 100% sure what the exact cause was. Pretty sure I was suffering from a combo plater.

I was getting a fail to chamber of one in about 10 rounds.
The kind where you have to lever open the bolt to get them out.

Here is what I suspect:
I was using a LEE turret press with 6 different turrets and I have multiple #4 shell holders.

After pulling my hair out, adjusting, re adjusting, and re adjusting again.
I think I narrowed it down to tolerance stacking between one shell holder and one turret. Thats because there is play in the turret that you have to adjust for and no two shell holders are the same size.
" Thats my story and I am sticking to it."

One other issue I have run into. Some 223 brass has fat heads. I suspect that is caused from being fired in a saw.

My solution to solve my hair pulling. May be extreme but having to lever open my bolt is some thing I have no patience with.

#1. Moved all my Rifle case sizing to a cast iron single stage press.
( this eliminates any slop in the process)

#2 I now use a small base sizing die.

#3 I check every sized case with a case head space gage.
( this catches the fat heads 100%. I cull those.)

This has solved my problem. Since I changed to this process. I have had zero fail to feed events. So I am happy.

Oh as a side note: Just to try it. I ran some 223 through my Hornady LNL AP. Sizing and priming on the press. I usually just load sized and primed cases on my progressives. Guess what came back? Yea back to my process.

 

[jepp2]

Am I correct in assuming that the chamber is a tad tight and that a small base sizing die will help?

Without knowing if you are measuring how much you are setting back the shoulder when you FL resize, can't tell. Do you measure the amount you are setting back the shoulder, or do you just screw the die down until it contacts the shell holder and give it another 1/X of a turn?

If you set the shoulder back the same as the factory ammo that chambers just fine and your reloads don't chamber, you need the small base die.

 

[Jay24bal]

Thanks for the replies so far. As to the questions:

I don't pretend to know a lot about AR building, but is it possible the barrel has a head spacing issue, maybe not screwed in enough?

Rifle is good to go. It cleared go no/go gauges and worked 100% with factory ammo.

#1. Moved all my Rifle case sizing to a cast iron single stage press.
( this eliminates any slop in the process)

I am using a cast, Lee single stage press along with the same dies I have made thousands of fully-functioning rounds in my other ARs before.

If you set the shoulder back the same as the factory ammo that chambers just fine and your reloads don't chamber, you need the small base die.

Yes, I not only measure OAL but also measure the case to the shoulder as well as the ogive of the bullet. According to my measurements, I should be good to go.

I am thinking a small base die is the answer.

 

[F. Guffey]

Rifle is good to go. It cleared go no/go gauges and worked 100% with factory ammo.

By all means purchase a small base die, I have a few, I do not need them but, I have them JIC.

For anyone else having troubler chambering sized cases I suggest they learn to measure a new, unfired, over the counter, factory case from the shoulder to the head of the case. I suggest saving one unfired case for comparison when sizing a fired case. I suggest a Wilson case gage, the very precision Wilson case gage that has been around since 1955.

For the advanced reolader the Wilson case gage can be used as a chamber gage, meaning it can be used to determine the diameter of the case head. I use chamber gages, there are times cutting the chamber from a barrel is a great source for chamber gages, and cheap, most smiths use old barrels to hold up tomato vines.

learn to measure a case for length, learn what is meant by minimum length and full length sized. And, know your press, know when the case whips the press, learn when the press whips the case. Then there is annealing.

F. Guffey

 

[F. Guffey]

Am I correct in assuming that the chamber is a tad tight and that a small base sizing die will help?

You have no choice, if you could measure the length of the chamber and the diameter of the chamber you would not have to assume.

Going back to the beginning, you fired 100 cases flawlessly, then you went to the stash of 3.400 pounds and that is where you deviated from practical practices. I would have suggested you measure the fired cases for length and diameter, everyone should know there is a small snap back/jump back/spring back of the case, your fired cases should have been measured for comparison with cases that are sized. Had you saved one new, over the counter factory round you would know what 'WII CHAMBER', had you saved a few of the once fired cases that fired flawlessly you would know the maximum length of the a cases that would chamber.

Am I correct in assuming that the chamber is a tad tight and that a small base sizing die will help?

By all means purchase a small base die.

F. Guffey

 

[Kimber84]

Small base aside, are you sure the cases were effectively resized

to SAAMI minimums and not left slightly long due to case and/or

press springback?



(And if you believe you're sure, why do you think so?)

X2 to this. Sounds like the bolt is being held open and is not rotating in, this causing the absence of a primer strike.

 

[F. Guffey]

press springback?

Methods and techniques:

how could a reloader determine if a case was sized before lowering the ram?

How could a reloader determine how much a press was going to spring back after raising the ram to the top when sizing the case?

Can a reloader determine how much of the case did not get stuffed in to the die when the ram is raised?

I have come to the conclusion reloaders are a proud people, too proud to bend over and check the gap between the bottom of the die and top of the shell holder, then there is the feeler gage, a modest and humble tool, when a case whips my press I know by 'how much', in thousandths. I have the directions for measuring with a light gage, I do not have a light gage, the cost is prohibitive, I am not too proud to use a feeler gage.

And there is nothing about me or my ego that prevents me from turning a press upside down to determine how it works and or does not work.

I have Rock Chucker presses, none of my Rock Chucker presses cam over. My Rock Chucker presses jam up, lock up and cram over. I have cam over presses, my cam over presses cam over.

F. Guffey

 

[mehavey]

reloaders are a proud people, too proud to bend over...

The image that comes to mind is not to be discussed in polite company.

That said, cam the (Lyman and/or RCBS box-design) press over by an 1/8 turn, hit the
case twice on the bottom stroke, and 99.44% of the time the OP will have reduced the
case to the die's SAAMI minimums. (Hornady a/o Prec Mic gauge would be great insurance.)

 

[tango1niner]

At the risk of starting some flames in my direction I feel WHENEVER reloading for a semi-auto you should be using a small base die. It's all about reliability... I want that round to chamber 100 % of the time. If you are hunting dangerous game I certainly don't want to hear a "click" instead of a boom. If you're shooting a match do you want an alibi, a stopage, FTF, and have to deal with the RO? I will take it further and say I don't want to hear "click" ever... except perhaps on a chamber I know is purposely empty.

ok, i'm ready... fire me up !

 

[Jay24bal]

My press does not cam over, and the die is seated all the way so that there is no gap in between the shell holder and the bottom of the die.

I stopped in at the LGS yesterday and they had small base sizing in stock so I picked it up and will give it a go. Hopefully this works.

Thanks.

 

[TylerOutdoorsman]

Have you tried a LEE Factory Crimp die? That's what I use as the final step when loading for a semi-auto rifle. That's solved all of my feeding issues in the past.

 

[mehavey]

My press does not cam over...

Out of curiosity, which press are you using?

 

[zxcvbob]

I don't have much experience with reloading rifle rounds; especially for a semiauto, but I've done it a little have some ideas anyway:

1) a small base die might be a good idea to use the first time you resize cases from the range-pickup bucket. (I just bought one for that purpose; having the same trouble as you every once in a while with my Mini-14) Use the regular sizing die on cases once you know where they've been.

2) I didn't see you mention anything about trimming the cases.

3) over-crimping might be causing the trouble. How does it work if you don't crimp at all?

I hope to learn something from this thread.

 

[Jay24bal]

I didn't see you mention anything about trimming the cases.

Yes, I measure every case and those that need trimmed, are.

Have you tried a LEE Factory Crimp die? That's what I use as the final step when loading for a semi-auto rifle. That's solved all of my feeding issues in the past.

Yes, every round has gone through the Lee FCD, set to a light crimp (just enough to get the brass to catch on the cannelure).

Out of curiosity, which press are you using?

I believe it is called the "Lee Reloader." It is the cast, "C" press made by Lee. I do all my rifle work on that press and save the turret press for handgun ammo as other than my AR fodder, all my other rifle loads are precision built for accuracy.