223/5.56 Sizing Die.

[BYJO4]

I've have decided to load some for my AR. Over all the years, I have never loaded for a semi auto rife. From the reading I've been doing, it appears that a small base sizing die is recommended. I would just like to confirm with some of you that load for your AR. Thanks

 

[Reloadron]

As to the SB dies it really depends on who you talk to. I have a set and have never had the need to use them. If you are buying large quantities of bulk once fired military brass once fired in a machine gun with a large chamber then yes they can be a good thing. If you are buying new factory brass or loading cases that were once fired in your rifle then I don't see a need for them.

Will they hurt? No, not really other than the argument they may overwork your brass and shorten its life. I typically load brass 4 or 5 times and pitch it unless it still looks good. If you want to run brass longer and get more loadings then yes, the SB dies will work it more and maybe shorten the life of the brass.

So are they really necessary? Depends on what you are loading and where the brass came from in my opinion. Will it hurt to buy SB dies as your first set? No, not really.

Ron

 

[plmitch]

Not needed. I reload for my ar with a regular old lee set of dies.

 

[243winxb]

Reloadron covered it well. Most dont crimp, but you have a choice in RCBS dies of 2 crimp types. Roll & taper. Taper is more forgiving with different case trim lengths, if you feel a need to crimp.

 

[RDA 226sig]

The previous posters pretty much covered it well. It comes down to the chamber in your firearm and the source of the brass. If I was buying a die set specifically for AR loading I would go with the SB die.

 

[grubbylabs]

You should also take a look at the RCBS X die. So far it seems to be working well for me. I also picked up the worlds finest trimmer for 223. I trim all new to me brass per the die instructions and then shoot away.

The X die and WFT sure seem to shorten brass prep time.

 

[cfullgraf]

From the reading I've been doing, it appears that a small base sizing die is recommended.

If you do not have any 223 Remington dies, I recommend buying a small base sizing die. Just a bit of insurance against chambering problems. With the AR-15, there are several different chambers out there and accumulation of tolerances between the chambers and the sizing die could cause problems.

If you already have 223 Remington dies, you will most probably not have any problems but know where your fired cases come from.

Range pick ups and purchased once fired cases may have been fired in a large chamber and you may have problems. Just be aware of the situation and act accordingly should you have chambering problems due to the body not being resized sufficiently.

Everyone's comments thus far are good.

 

[rcmodel]

I have reloaded for AR-15's, Mini-14,s, and bolt actions for over 43 years with standard RCBS .223 dies.

IMO: There is never a need for Small-base dies until someday, you MIGHT buy a rifle with a tight chamber that needs one.

The rest of the problems people have is, they don't know how to adjust a standard sizing die properly in thier press.

rc

 

[kilibreaux]

Standard Lee dies will squeeze your cases down adequately to feed in an autoloading rifle.
So called "Small base" dies date from antiquity when few rifle shooters were doing autos and sizing for bottleneck cases was all about the neck leaving the body "expanded" or very much so because this preserves case life and accuracy.
Autoloaders need full length sizing and most modern dies will deliver this if screwed down so the shell holder is in contact with the die body during sizing and you're using dies that also compress the case body.

 

[steve4102]

From Sierra's "Loading for Semi Autos and Service Rifles".

Despite the oft-repeated advice that autoloaders, pumpguns and lever-actions require small base dies, the Service Rifles may be the exception that proves the rule. While it’s true that all of these action types lack the powerful camming forces of a bolt-action, the more generous chamber dimensions common to most Service Rifles are normally compatible with standard dies. Please understand that this is a general statement, and that there are exceptions to this. The point is, you don’t need to automatically go to a small base die set. Most of the standard reloading dies produced by reputable firms, such as RCBS, will resize fired brass properly to work in these rifles.

Link

http://www.exteriorballistics.com/reloadbasics/gasgunreload.cfm

 

[moonzapa]

If you are a pleasure plinker and don't mind an occasional stove pipe, or a failure to go to full battery, then continue to use standard dies for your AR platform rifle. For me, I want it to go bang every time. It's one less item in the equation to cause a failure and to me it's worth using. If I could do it over again, I would not have purchased an AR-10 rifle. I would have been much better off buying a Sig, MIA, or Ruger SR-762, etc. That's another subject and I'm getting away from your post. Good Shooting!

 

[Potatohead]

Reloadron covered it well

They dont call him ReloadRon for nuttin' lol

 

[pretzelxx]

Well, I plan on getting the rcbs x die for sizing and the Forster ultra micrometer seater. 110 for both, but makes seating super easy and the sizing reduces overworking the neck so you can use it more.