Small base dies are generally not needed and here are some indicators to look for to make the decision.
First off take about five fired cases from the rifle in question and measure the base of the case in the web area .200" from the rim. (308 Cases will normally give you .471" to 473" and I have seen .475" from some chambers.
Next resize the cases and measure them the same way.
Generally all 308 FL dies will size the base down to around .468". Thusly if you have fired cases measuring .471 or larger and sized cases measuring .468" /.469" you are obviously have .003" to .004" clearance between chamber wall and case and trying to size smaller has no relation to case base dimension.
A new 308 commercial case generally measures .465" and LC cases measure .468" so you won't find 308 dies going much less in base dimension.
OK lets say you have hard closing but the above dimension shows you have a smaller sized case than the chamber so where is the problem?
Hate you tell you guys this but there is one hell of a lot of dies floating around that are chambered too deep at the manufacturer and even running the die all the way to the shell holder just won't size the shoulder. Everyone knows when you size a case it gets longer.
What everyone does not know is the shoulder goes forward and if the die is chambered too deep the shoulder will not be moved enough to set it back thus the case shoulder jams the chamber shoulder.
Not to worry guys it is a VERY EASY FIX. If you have a buddy with a lathe remove the lock ring and expander and chuck the die in lathe and take off about .010" from bottom of FL die. This will allow the die to go further down before touching the shell holder and thus you are bringing the shoulder down with it.
I have about 55 sets of dies and I figure I have had to turn the bottoms off 15 of them in order to get them to size correctly. I have also had to dress dies for others.
On a couple I have had to cut .015" from bottom of die to get them to size.
Make sure you recut the radius on the bottom of the die like it came. This can be done with emergy cloth.
I also use L.E. Wilson Case Gages and MO Gages. The L E Wilson gages will tell you right quick whether your case is sized to "factory" specs thusly you need one for the calibers you will fire especially in gas guns. FL size a case and drop in the Wilson and it will tell you everything you need to know. It will also tell you the length of the case for factory specs.
In my bolt guns I use MO Gages. I adjust my dies so the shoulders of my cases are only bumped back .001 to .002".
I have rifles with very tight chambers and zero headspace all the way to jumbo factory chambers and I don't use a SB die for anything. I have four 308 reamers. Necks at .337, .339, .341 and .344. The base dim I generally order in 308 is .468" to 4685" this with headspace at zero and neck at .339 nothing on the case moves over .002" upon firing and this makes for long case life if LC cases are used.
So before you lay out a wad for a SB die do some measuring and see exactly where your problem is.
As well you may have problem a die won't fix. Case in point friend had a 300 Win Mag. Factory ammo would work fine but dies would not size right. He bought a total of three sets of dies and none would allow him to fire a reload. I told him to bring it down and some ammo and I sized cases with my die and I knew he had a chamber problem.
I unscrewed the barrel, set it back one thread and rechambered it with my tight 300 Win Mag die to zero headspace and all his reloaded ammo chambered and shot fine. It was a bad chamber reamer that cut factory chamber. Mine was a custom (tight base/neck) 300 Win Mag reamer by Dave Manson and my friend is tickled no end with his rifle now.
So before you jump up and start throwing money out for SB dies measure what you have and what you get and trace down where the problem is. As indicated first thing to get is a L E Wilson case gage so you know where you are going and can determine why you are not getting there.
First off take about five fired cases from the rifle in question and measure the base of the case in the web area .200" from the rim. (308 Cases will normally give you .471" to 473" and I have seen .475" from some chambers.
Next resize the cases and measure them the same way.
Generally all 308 FL dies will size the base down to around .468". Thusly if you have fired cases measuring .471 or larger and sized cases measuring .468" /.469" you are obviously have .003" to .004" clearance between chamber wall and case and trying to size smaller has no relation to case base dimension.
A new 308 commercial case generally measures .465" and LC cases measure .468" so you won't find 308 dies going much less in base dimension.
OK lets say you have hard closing but the above dimension shows you have a smaller sized case than the chamber so where is the problem?
Hate you tell you guys this but there is one hell of a lot of dies floating around that are chambered too deep at the manufacturer and even running the die all the way to the shell holder just won't size the shoulder. Everyone knows when you size a case it gets longer.
What everyone does not know is the shoulder goes forward and if the die is chambered too deep the shoulder will not be moved enough to set it back thus the case shoulder jams the chamber shoulder.
Not to worry guys it is a VERY EASY FIX. If you have a buddy with a lathe remove the lock ring and expander and chuck the die in lathe and take off about .010" from bottom of FL die. This will allow the die to go further down before touching the shell holder and thus you are bringing the shoulder down with it.
I have about 55 sets of dies and I figure I have had to turn the bottoms off 15 of them in order to get them to size correctly. I have also had to dress dies for others.
On a couple I have had to cut .015" from bottom of die to get them to size.
Make sure you recut the radius on the bottom of the die like it came. This can be done with emergy cloth.
I also use L.E. Wilson Case Gages and MO Gages. The L E Wilson gages will tell you right quick whether your case is sized to "factory" specs thusly you need one for the calibers you will fire especially in gas guns. FL size a case and drop in the Wilson and it will tell you everything you need to know. It will also tell you the length of the case for factory specs.
In my bolt guns I use MO Gages. I adjust my dies so the shoulders of my cases are only bumped back .001 to .002".
I have rifles with very tight chambers and zero headspace all the way to jumbo factory chambers and I don't use a SB die for anything. I have four 308 reamers. Necks at .337, .339, .341 and .344. The base dim I generally order in 308 is .468" to 4685" this with headspace at zero and neck at .339 nothing on the case moves over .002" upon firing and this makes for long case life if LC cases are used.
So before you lay out a wad for a SB die do some measuring and see exactly where your problem is.
As well you may have problem a die won't fix. Case in point friend had a 300 Win Mag. Factory ammo would work fine but dies would not size right. He bought a total of three sets of dies and none would allow him to fire a reload. I told him to bring it down and some ammo and I sized cases with my die and I knew he had a chamber problem.
I unscrewed the barrel, set it back one thread and rechambered it with my tight 300 Win Mag die to zero headspace and all his reloaded ammo chambered and shot fine. It was a bad chamber reamer that cut factory chamber. Mine was a custom (tight base/neck) 300 Win Mag reamer by Dave Manson and my friend is tickled no end with his rifle now.
So before you jump up and start throwing money out for SB dies measure what you have and what you get and trace down where the problem is. As indicated first thing to get is a L E Wilson case gage so you know where you are going and can determine why you are not getting there.
