Dies

[RonS]

I am kind of new at reloading and don't know a lot about it as of yet. Right now I'm loading .223's for my AR. I am using a Lee Deluxe Die Set at the moment. Someone mentioned to me I should try "small base dies". Can anyone explain what small base dies are and do? Thanks
Monte'

 

[Kenny474]

Small base dies are a full length sizing die that will completely resize the case down the the extractor groove, essentially sizing the neck, pushing the shoulder back, sizing the case body, and it is a few thousandths tighter (will size the case smaller) than a standard FL die at the die opening so as to size the case a bit smaller towards the base of the case above the extractor groove. They will help when you are loading for a semi-auto as the cases will feed easier.

Since you are shooting an AR-15 you should be using the full length sizing die that is in your set. Lee deluxe dies come with a collet neck sizing die (best used with a bolt action), a full length die, and a dead length bullet seater.

You don't want to use the collet die with a semi-auto as it only sizes the neck and cases that have been previously fired will be formed tightly to the chamber and will often have feeding issues in semi-auto actions as the rounds fit tighter and take more force to chamber.

The full length die is the one in your kit with the hex nut at the top with a decapping rod sticking through it. The collet die has a knurled knob at the top the same diameter as the die itself. I am sure you know which is the bullet seater if you have used them before.

You don't necessarily need a small base die. I use Lee full length dies for my semi-auto and also used them for my DPMS LR308 AR-10 and I have yet to have any feeding issues. The only reason you would need a small base die is if you were having feeding issues when your cases are sized with the full length die already.

If you use the full length die according to the instructions you should be fine. You put the shell holder on the ram and raise the ram to the full up position and screw in the full length die until it contacts the shell holder plus 1/4 to 1/2 turn. You add the extra turn to compensate for any press flex and to insure you are making solid contact between die and shell holder. You want to use a steady stroke and be sure the die makes firm solid contact with the shell holder. You don't want to smash them into each other, just firm steady pressure the whole stroke while insuring you apply firm pressure when the die makes contact.

If you have any other questions about your dies or small base dies just ask.

Kenny

 

[Kenny474]

You also want to crimp your bullets when used in an AR-15, as the hard fast chambering cycle can push an uncrimped bullet back into the case which will raise pressure dangerously high.

Using the crimp operation built into most bullet seaters (I am unsure if the dead length seater has this feature) is less than ideal, as you must be critical with trim length or you will get uneven crimping from case to case and even buckle cases that are longer than the case you set the die up with.

If you don't have one already, go buy a Lee Factory Crimp Die. They apply an even crimp regardless of case length, and have zero chance of buckling cases. They also make a far superior crimp that is much better than a roll or taper crimp. Also, you don't need to be critical with position of the cannelure at the case mouth as you would with a typical roll or taper crimp, or even use bullets with a cannelure.

You definitely want to be crimping your bullets for safety reasons. The best way is with the Lee FCD. It's very inexpensive and worth every penny when loading for an auto.

I also did some research (looked at mine), your seating die doesn't offer a crimp function, so you will need some way to do this.

 

[RonS]

Kenny474, thanks for the info. I will be calling Lee to order a small base die for my AR and use the deluxe set for my bolt gun. I bought my dies used and they also came with a RCBS comp seater and a Lee crimp die but was told it would cause high pressure and to only use it with 5.56 NATO chamber. My AR is a .223 with a 1:14 twist and my bolt gun has a 1:8 twist.

 

[Kenny474]

Lee doesn't make a small base die set. RCBS does, but unless you are having a feeding issue when using a standard full length die than all it will do is excessively work your brass and wear out your cases faster. What you want is a standard Lee full length die. I don't want to see you get another die you already have or one you don't need. So you need to help me figure out what you actually have. If you have a camera, posting a pic of all the dies you have will make this really easy.

Your Lee Deluxe die set should already have a Full Length die, and that is all you will need. I am going to give you a link to the deluxe die page on Lee's site. It will explain that both the collet die and full length die are included.
http://www.leeprecision.com/cgi/catalog/browse.cgi?1280634535.493=/html/catalog/dies-dlxrifle.html

First off, we need to figure out exactly what you actually have for dies.
I think either you or I are getting confused about what you have for dies, and what the deluxe die set consists of. The Lee deluxe set comes with 3 dies: a dead length bullet seater, a collet neck sizing die, and a full length sizing die.
The RCBS comp seater was added by the previous owner, which you probably knew. And if you actually have the deluxe dies, the crimp die was added as well.

First off, are your dies in a Lee box or a round Lee container that has a base the dies screw into and is red in color? If they are in a Lee box it will have a clear plastic lid and be either red or yellow. Pacesetter dies come in red, deluxe in yellow.

Now you need to help me figure out what dies you actually have by matching them to my description.
The full length sizing die will have a hex nut on the top with the decapping rod in the center of the hex nut.
The collet die will have a knurled knob the same diameter as the die body.

The die with the hex nut is what you need to use. No small base necessary.

And as far as the crimp die raising pressure, it's pure BS for the most part. It can be used safely on either .223 or 5.56NATO brass, in either your bolt gun or your AR. By crimping the rounds you will raise shot start pressure, as it takes more energy to get the bullet to move than if it isn't crimped. Benchrest shooters do this by jamming bullets into the rifling. If you raise the shot start pressure it will help give you consistent ignition and improve the accuracy and consistency of bullets loaded to mag length and not jammed into the rifling.

You should develop your loads with a crimp if you plan to crimp, as crimping after you have an accurate load will change the tune and could have a negative effect on accuracy.

Please understand that it is FAR more dangerous to shoot uncrimped bullets in a semi auto than to crimp your rounds. If you get a bullet that gets pushed back into the case you WILL have a serious pressure spike that could ruin your whole week, possibly your life.

Also, know that most all factory rounds are crimped, so the high pressure line truly is BS.

 

[RonS]

Kenny, I have a complete set of Lee deluxe dies in a round yellow container as you discribed plus a seperate Lee crimp die in a green box and a RCBS comp seater in a gray box which I purchased from a gentlemen who know longer was able to shoot. I did have a feeding problem while at the range one day when a couple of rounds, the bullet tips jammed into the lugs but did not push the bullet back into the case, cases were crimped. The person seated next to me saw this, he advised me to get a small base die and stop crimping. That is what brought me to ask the question.

 

[Kenny474]

OK, that makes perfect sense as far as what you have for dies. But that was the worst advice ever in regards to crimping. So if it happens again the bullet will stuff back inside the case and possibly chamber, which is going to create a huge issue. Not good advice.

If the jam was caused by the bullet hitting the locking lugs, than it's a mag issue or OAL issue. If the rounds were only going part way into the chamber and hanging up because the case diameter was too large, than a small base die will help. Small base dies are not going to help a jamming issue.

Sorry about the other post, I was a bit confused as to what dies you had as it sounded as though you had just one miss-matched set.

If the jamming is only occasional and only happens to a few rounds or with a certain mag, I would keep the round and inspect it for flaws and also the magazine as well.

 

[RonS]

Kenny474, being a mag problem makes better sense to me now that you have explained the purpose of the small base die. My OAL with a Berger 40gr bullet was only 2.240. Sorry if I confused you about the dies but I didn't realize it made a difference. The next time I go to the range I'll know better than to take advise from a ..."joker", I have been reading these blogs for sometime and now I know where to go for good advice. And those "jokers" say you guys don't know jack! Thanks for all your help and I hope we can talk again.