Small Base vs. Full length re-sizing

Remington1981

My question is; what is the difference between the two? I use a small base die for my AR, because I was told that you had too so that the cases would not jam. Does it hurt the Accuracy by using small base dies?

Tailgunner1954

The only difference between a SB and a "regular" FL die is that the SB sizes just a little further down the very bottom of the case.
The "base" of the case is the end with the headstamp and extractor groove. Due to the radius/taper at the mouth of the sizing die, this area dosn't get sized with a "regular" die, but the smaller amount of radius/taper of the SB die allows it to "reach" a little closer to your shell holder. Other than that small difference, the 2 types of dies are identical.
As to weather or not you need a SB for your AR, would depend on how oversize the chamber the brass was origionaly fired in was. Back when fired from a Machine Gun (with their oversize chambers) 30-06 & 308 brass was common, the SB dies were often needed even for a bolt gun.

Remington1981

quote:Originally posted by Tailgunner1954
The only difference between a SB and a "regular" FL die is that the SB sizes just a little further down the very bottom of the case.
The "base" of the case is the end with the headstamp and extractor groove. Due to the radius/taper at the mouth of the sizing die, this area dosn't get sized with a "regular" die, but the smaller amount of radius/taper of the SB die allows it to "reach" a little closer to your shell holder. Other than that small difference, the 2 types of dies are identical.
As to weather or not you need a SB for your AR, would depend on how oversize the chamber the brass was origionaly fired in was. Back when fired from a Machine Gun (with their oversize chambers) 30-06 & 308 brass was common, the SB dies were often needed even for a bolt gun.


Thanks you very much.. Now it makes sense as to why my .223 brass is the only ones that I have trouble "sticking" cases in.. Thanks again

charliemeyer007

I like the Lee sizing lube because it doesn't kill primers and it works good. For really hard sizing the Redding/Imperial sizing die wax is the best I have found.

tsr1965

SB dies are often needed for reliable function of any semi-auto, pump, and some lever actions taking high pressure bottleneck rounds. This includes AR's, AK's, BAR, Remington's(740,742,4,7400,760,6,7600), FAL's,HK's and many others. I am not saying that 100% will need the SB, but 90% will. The best sizing lube I have found is the Hornady One Shot, wax based, spray lube. It is awesome. Our Handloading moderator JustC, would be able to add to this.

mrbruce

I imagine the only thing Justc will add is to use Imperial Die Wax [:D]