Failure to fully chamber round

[Waterwolf]

I purchased a Dillon shell checker. The worst loaded round was .006 past the max. Yes that is past the max, but would that cause the bolt to hang up before going into battery??? Seems like the bolt is out quit a way. Could it be the gun? there are 3 AR15's doing this same thing. Also the round is getting jammed into the chamber. We have to pull back on the charging handle and smack the but to the ground to dislodge the shell. No one has been hurt so far, but really would love to solve this issue. So come on smart guys, please help.

[bigbird34]

Have your measured the brass and trimmed it to length ?
BB34

[Tim R]

This a common problem for new 223 AR hand loaders, I once had this problem as well. I was trying to load like I did for my match tuned 308 M-1.

The case needs to be sized down further. I tighten my die down until I don't have any light between the die and the shell holder with a case in the shell holder and in the die with the ram all the way up. It also means the shell holder and base of thee die will be very tight when the ram is up and there is not a case being sized. A small based die won't fix it either.

[Steel Talon]

FWIW
Sounds like the shoulder. Alot of AR's experience this problem. A small base die should take care of it.

Peace
Steel Talon

[Waterwolf]

What are the advantages of a small base die??

I have checked my shell length, and all seems fine.

I'm using a Dillion 650, and the shell sizer die is set all the way up.

[Waterwolf]

The shell did appear to have some shoulder marks.

[Tim R]

Does the shell holder and the bottom of the die have any light between them when the ram is all the way up and there is a case in the die? If there is, the die needs to be turned down some more. Progressives have more flex than a "O" single stage. One way I check my sized brass is to place a sized case in the chamber and close the bolt. Does the bolt close and then eject the case easily when the charging handle is pulled? If not then you are going to continue to have problems.

[Waterwolf]

I had the die all the way down, with the locking nut. But removed the locking nut and put it below the loading block, if that makes sense. So the nut is now below the fixture that the die threads into instead of on top. It should work that way. I don't have any more time to play tonight with the reloader. But ran one shell through, and it was right on the money. EXCEPT the shoulder was crimped in. So I'm assuming that it is now to low. Any thoughts?

[steve4102]

I had the die all the way down, with the locking nut. But removed the locking nut and put it below the loading block, if that makes sense. So the nut is now below the fixture that the die threads into instead of on top. It should work that way. I don't have any more time to play tonight with the reloader. But ran one shell through, and it was right on the money. EXCEPT the shoulder was crimped in. So I'm assuming that it is now to low. Any thoughts?

Sorry, but you have me a bit confused. Have you followed the instructions that came with your FL dies. They need to be set up correctly or all hell breaks loose.
Here is a quote from RCBS as to the proper way to "Generically" set up your FL dies.
Step 5: Install the Sizer Die

Thread the sizer die into the press until the die touches the shell holder when the ram is at the top of the press stroke. Raise the press handle and turn the die down another one-eigth to one-quarter of a turn and set the large lock ring. If you're using a carbide sizer die, make slight contact with the bottom of the die and the shell holder.

If you are not doing this then you will always have feeding problems in your "gas-guns".

[Slamfire]

I purchased a Dillon shell checker.

You mean one of these?

Yes that is past the max, but would that cause the bolt to hang up before going into battery???

Yes it could, and it has in other folks AR's.

You need to size the case to fit in the chamber. If possible you would like to set back the case shoulder about .003” from the fully expanded condition it comes out from the rifle. In no circumstance do you ever want to size it more than .006” as you are likely to get a case head separation on the next firing. There have been instances where I followed the die manufacturer's instructions and I got a crush fit in the rifle chamber because the sizing die did not set the shoulder back enough. In some instances I have had to grind material off the bottom of a sizing die to get sufficient case sizing. Just take the instructions that the factory sends with their dies, and toss out the part that tells you to size to the shellholder. Or shellholder plus a ¼ turn. You will find that such guidance is inaccurate at best, rubbish on the average.

This web site is really useful for showing how to use case gages. I recommend looking at the pictures, and it explains the special case gages needed for the belted cartridges.

http://www.realguns.com/Commentary/comar46.htm

[Alleykat]

You don't need a small base die to properly bump the shoulder; just set the sizing up correctly, using the case gage. The case head should be above the bottom of the cut and below the top of the cut.

[30Cal]

If the shoulder is buckling then you're probably crimping too much.

[Alleykat]

I just don't crimp .223s.

[Tim R]

If the shoulder is buckling then you're probably crimping too much.

My thought is maybe Waterwolf is using too much case lube. I have never seen a shoulder buckle in a size die. I have seen oil dents.

But 30Cal could be right. I've seen some messed up cases come out of the seating/crimp die. A few of them were mine. I don't use a crimp on my 223.

Before I would grind on the bottom of a die, Redding has some shorter shell holders which puts the case in the die a little further.