Small Base Dies

03psd

Sergeant
Full Member
Minuteman
May 27, 2006
567
34
Oklahoma
When and Why?

I did a little reading on them and their use seems to be limited to autoloaders,yeah?

Other than possibly overworking the brass, any down side?
 
Re: Small Base Dies

Why?

When some snug chambered rifles with low camming power - autoloaders, pumps and some levers - can't fully chamber a normal reload (which is usually designed to be a tad larger than most factory ammo) we need to fully restore the case's base to factory norms, or a "small(er) base" by a couple or three thou. It's not a lot of difference but it can make a world of difference in chambering.


When?

Any time you actually have a problem chambering the reloads. But, if YOUR rifle swallows conventionally sized ammo you are better off NOT using a SB die because it will decrease case life somewhat.
 
Re: Small Base Dies

Small base dies are typically used for rifles with match chambers. I recently ran into this problem as I have an AR15 with a match chamber. It will chamber virgin rounds but will not chamber rounds that have been resized on standard dies. From what I have been told, I will have to resize with small base dies.

There is no other advantage to using small base dies that I know of and it will only work the brass more than needed.
 
Re: Small Base Dies

I use small base dies for my two match rifles. These two rifles have very tight match chambers. Virgin brass fits in nice and tight but since I load very hot (F-class loads) the base of the case tends to expand after a few loads. The S/B dies allows me to control that because they force this part of the case back into the proper dimension.

This means that load after load, my cases are always easy to chamber and for me that makes life easier. The last thing I want to do is close the bolt on 70+ hard to chamber and then extract rounds during a match. Lying prone with the left hand holding the rear bag and not moving for an entire string, my right hand appreciates the fact the bolt opens and closes easily all the time.

Since I use the SB dies all the time, I have not noticed any reduced case life, so color skeptical on that aspect. For my non-match chambered rifles, regular dies are fine, but these cases will simply not fit in my match guns.

I find there is no more effort resizing with an SB die than there is with a regular die, provided the SB die was used throughout the life of the case. I have tried resizing with an SB die a case that had been resized 3-4 times with a regular die, never again.
 
Re: Small Base Dies

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ChadJamesR</div><div class="ubbcode-body">Small base dies are typically used for rifles with match chambers. I recently ran into this problem as I have an AR15 with a match chamber. It will chamber virgin rounds but will not chamber rounds that have been resized on standard dies. From what I have been told, I will have to resize with small base dies.

There is no other advantage to using small base dies that I know of and it will only work the brass more than needed.

</div></div>
If used correctly a small base die wil not overwork a case used in a tight match chamber. Quite the opposite infact if the small base die is a body die. Because that match chamber only allows minimum expansion of the brass you can resize only the minimum amount to get the case back in the chamber. This then is far less working of the brass than happens in standard chambers with standard dies.
 
Re: Small Base Dies

"I use small base dies for my two match rifles. These two rifles have very tight match chambers.Since I use the SB dies all the time,.. I have not noticed any reduced case life, so color skeptical on that aspect."

Of course not, not in your tight chambered match rifles but how would you know without compairing to standard dies?

I suspect you would have noticed a difference if you had conventional factory chambers and that was clearly what I addressed, was it not??
 
Re: Small Base Dies

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fuzzball</div><div class="ubbcode-body">"I use small base dies for my two match rifles. These two rifles have very tight match chambers.Since I use the SB dies all the time,.. I have not noticed any reduced case life, so color skeptical on that aspect."

Of course not, not in your tight chambered match rifles but how would you know without compairing to standard dies?

I suspect you would have noticed a difference if you had conventional factory chambers and that was clearly what I addressed, was it not?? </div></div>

I'm not sure that I either grasp what you just said, or that you understood what I said earlier.

However, I have tried regular dies for resizing in my match chambers. They were iffy at best and that was after the first reload. Switching to SB dies and restarting with new brass cured all my problems. I have brass that has had 5 loads in my match AR and they still look like new. The .308 brass has had several loads and is also in perfect accordance to specs.

Resizing takes virtually no effort and loading & extraction is perfect. What more could I want?

And I keep pointing out that these two rifles have very tight match chambers.
 
Re: Small Base Dies

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BOLTRIPPER</div><div class="ubbcode-body">SB dies are a MUST in them chamberings that the brass grows at or near the base....very much like a belted magnum....because the case head-spaces off the belt.... </div></div>

Some say that a SB die wont get it done on a belted magnum case. I dont recall the name but there is a special die with a collete that a guy invented that is supposed to do a great job on belted cases because it sizes all the way down to the belt which SB dies dont. Or so I have been told.
 
Re: Small Base Dies

"SB dies do not overwork the brass. They size the base of the case an additional .001" over what standard dies do."

More like .003". I figger any working past what's absolutely needed is "overworking", guess we differ on that.