Small base dies

[Gator]

I'll be getting into reloading .223 in the near future and I have a question about dies. I have seen reference to small base die sets. Based on what little I know I have a few questions.

Are small base dies a requirement for any / all semi autos or is it dependent on the fit of a particular rifle's chamber?

I'm guessing if I use small base dies for my semi auto it won't cause any problems if I use the same dies for bolt gun reloading.

Tell me what I don't know as far as small base vs standard dies so I know what to buy.

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[ronn47]

If you have one gun generally you don't need small base dies.
If you are loading for different guns (semi-auto, single shot, bolt let's say) then you need to use small base dies.
Small base dies takes your brass back down close to factory specs.
If you are loading for one gun only then the normal spring back of the brass will allow your reloaded ammo to work (most of the time).

 

[GymB]

I have a small base sizing die, but haven’t needed it. I thought that I’d need it for sizing mil brass for my ar, but I don’t. Thinking about a bolt gun in 223, and maybe I’ll need it to convert mil brass for that, we’ll see. Won’t be moving brass back and forth between platforms, so only expect to use it once if at all.

I’d wait until you need it.

 

[Toprudder]

I have not seen - yet - where I need small base dies. I use a lot of range brass, and load for 3 different AR rifles. YMMV

 

[contender]

It depends.
Chamber dimensions can vary between manufacturers or even just because of new vs worn reamers. it's a SMALL variation usually. However, as noted above,, if using mixed brass,, combined with different actions,, (semi, bolt, single-shot, etc,) you may want to use a small base die to prevent the possibility of sticking ammo or brass.
I have seen it happen,, more than once.
The last place you want an ammo malfunction is when it's NEEDED.
And in serious reloading,, if you keep brass separate for each firearm, or are just loading for competition etc,, then once a piece of brass is used in that gun's chamber,, neck sizing is often preferred by many. And there are other reasons to use or not to use a small base die. These are just a few examples.

So,, as mentioned,,, "it depends."

 

[Gator]

FWIW, I do intend on keep brass separate between semi auto and bolt gun.

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[Dale Gribble]

I use SB dies for .223 and the reason I use them is because I want my ammo to work in any .223/5.56 AR platform I have in my hands at the time, whether it’s my rifle or one I may have to pick up and use.

I don’t tailor any of my 5.56 loads to work in any specific rigs I have, but all of them...and others, if necessary.

 

[Amanda4461]

FYI-if you have a match barrel, like a Krieger or Shilen, etc., you will want the small base die. The custom barrels for match shooting or critter work at long range, are made with tighter match chambers , rather than normal NATO chambers, that were designed to work in burst or full-auto mode. Small base sizing just because you have the die set, but not a match chamber, will work-harden the brass and you’ll get less reloads out of the case before it fails.

 

[Charlie]

I have never had any small base dies and have never had any problems with any of my autoloaders in 223, 308, or 30/06 that required small base dies.

 

[Sasquatch]

I don't like small base dies- I've got some posts on here about it. To me, they're really for under-sizing the brass so it will fit in any dirty chamber. I got rid of mine and only use normal dies.