Small base sizer die for semi-auto?
- Thread starter Potshot21
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I've never used small base dies when reloading for semis and never had an issue. I even tried neck sizing and got about 80% of the rounds to function.
I was using Lee dies which some reports say are between regular dies and small base dies in dimension though.
I put about 1000rnds of reloads through my M305 before selling it and never had an issue. If you have a smaller than normal chamber you may need a small base die but that would have to be assessed on a case by case basis.
I was using Lee dies which some reports say are between regular dies and small base dies in dimension though.
I put about 1000rnds of reloads through my M305 before selling it and never had an issue. If you have a smaller than normal chamber you may need a small base die but that would have to be assessed on a case by case basis.
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Isn't RCBS the only company that even offers small-base dies? The other die makers don't seem to find them necessary. That kind of tells me they are a gimmick.
Heard the same thing too. Maybe this is why RCBS put out the small base die.
I have small base dies in .223 and 30-06, the dies only make the diameter at the base a .0005 smaller than a standard die. The big difference is the die sizes further down the case insuring the case will chamber. I use these dies if I buy once fired brass or use range pickup brass to bring the case back to minimum dimensions. Once the case has been sized with the small base die normally you can use a standard sizing die because military chambers are larger in diameter and headspace.
I'm loading for 3 different AR15 rifles so I use the small base die all the time due to the slight differences in chambers.
Bottom line, in most circumstances all you need is a standard sizing die for military chambers and if a chambering problem does happen you can always pickup the small base die.
I'm loading for 3 different AR15 rifles so I use the small base die all the time due to the slight differences in chambers.
Bottom line, in most circumstances all you need is a standard sizing die for military chambers and if a chambering problem does happen you can always pickup the small base die.
The big question is how tight is your chamber.
The norc chambers are generous and any fl die should be fine. My lee dies will leave my cases at 1.634, which would be to tight for a 1.632 match chamber. Most nor chambers run around 1.64 and >
The norc chambers are generous and any fl die should be fine. My lee dies will leave my cases at 1.634, which would be to tight for a 1.632 match chamber. Most nor chambers run around 1.64 and >
Below is an example of chamber diameters, the military 7.62 NATO chamber is .0035 larger in diameter than a match chamber and .0025 larger than a standard SAAMI chamber. "Generally" a standard resizing die is all you need on a "normal" milsurp rifle and you will need to adjust the dies for the rifles longer headspaced chamber. Meaning the resizing die will be adjusted higher than normal so you do not push the shoulder back too far.
The .223/5.56 military chamber is the same as above and the military chamber base diameter is .002 larger than SAAMI standards. Meaning in most cases the normal resizing die is already a "small base" die.
I also stated I have small base dies and another reason I have them is military brass is made to higher standards and is harder in the base than commercial cases. "IF" you load commercial cases "HOT" in a larger diameter military chamber you "might" need small base dies to bring the softer brass back to proper tolerances and dimensions.
This is why I said try standard dies first and then buy small base dies "IF" you need them. The problem is nothing is written in stone, not everyone has the same size chamber, not everyone uses the same type brass and sizing dies are made to plus and minus dimensions.
The .223/5.56 military chamber is the same as above and the military chamber base diameter is .002 larger than SAAMI standards. Meaning in most cases the normal resizing die is already a "small base" die.
I also stated I have small base dies and another reason I have them is military brass is made to higher standards and is harder in the base than commercial cases. "IF" you load commercial cases "HOT" in a larger diameter military chamber you "might" need small base dies to bring the softer brass back to proper tolerances and dimensions.
This is why I said try standard dies first and then buy small base dies "IF" you need them. The problem is nothing is written in stone, not everyone has the same size chamber, not everyone uses the same type brass and sizing dies are made to plus and minus dimensions.
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Nobody needs a small base sizer, well, nobody needs one until they need one. Then they do.
About once a week we get someone suggesting that someone else should grind down their resizing die some unknown amount because of chambering problems. What that can do negatively to headspace is considerable.
I've got 4 small base dies in 4 different calibers and use them a lot. Granted, that's mostly on minimum spec match chambers but they also often get used when I want ammo to feed through like factory. They have earned their modest cost back by civilizing brass fired in a generous chamber that won't chamber easily in another rifle even after full length sizing. I've done many hundreds of those for friends that got a pile of free brass from others.
By taking out the decapping assembly on a small base .300 Win die it becomes a body die for .257 Weatherby and 7 mm Rem mag. Probably .264 too although I don't have one and haven't checked.
The 30-06 SB die I got for a BAR will put a little extra base squeeze on .270 and 25-06.
The .308 SB die does the same for .243 and I suppose 7-08.
I use SB dies at times when ammo will be used interchangely between two or more rifles. When the kids are practicing with their .223s, or we are shoveing handfuls of 30-06s into mags, or my son is going to use my .300 ammo instead of his practice ammo I just want the stuff to work. A stuck live round gets old real quick.
About once a week we get someone suggesting that someone else should grind down their resizing die some unknown amount because of chambering problems. What that can do negatively to headspace is considerable.
I've got 4 small base dies in 4 different calibers and use them a lot. Granted, that's mostly on minimum spec match chambers but they also often get used when I want ammo to feed through like factory. They have earned their modest cost back by civilizing brass fired in a generous chamber that won't chamber easily in another rifle even after full length sizing. I've done many hundreds of those for friends that got a pile of free brass from others.
By taking out the decapping assembly on a small base .300 Win die it becomes a body die for .257 Weatherby and 7 mm Rem mag. Probably .264 too although I don't have one and haven't checked.
The 30-06 SB die I got for a BAR will put a little extra base squeeze on .270 and 25-06.
The .308 SB die does the same for .243 and I suppose 7-08.
I use SB dies at times when ammo will be used interchangely between two or more rifles. When the kids are practicing with their .223s, or we are shoveing handfuls of 30-06s into mags, or my son is going to use my .300 ammo instead of his practice ammo I just want the stuff to work. A stuck live round gets old real quick.
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