Here is some good info from Sierra.
Edited to move this to it's own thread, and sticky'd due to the importance. Thanks for this info, it is priceless.
Nickle.
I have talk to a couple of loader at work about the small base dies. It's surprising that they had not heard of this type of die. After researching semi-auto reloading it look like the small base die is only mentioned as an after though. But, they defiantly solved the problem of resized brass that dose not want to chamber. I will put it to work tomorrow.
Thanks wcmartin1 for take the time to post the info.
You should only use the small base dies if the regular resizing dies don't work for your rifle. I've reloaded for numerous semi-auto rifles in .223, .308, and 30.06 and never had an issue with the standard dies. The use of a small base die when you don't have to have one is said to greatly reduce the number of reloads you get from your brass due to the "work" done to the brass to resize it down to the smaller diameter (that's what the small base die does) each time you reuse it.
If someone has never had an issue they've never had to buy the small base dies.
Have a good one.
Quote from: M1A4ME on January 19, 2008, 10:34:39 PM
You should only use the small base dies if the regular resizing dies don't work for your rifle. I've reloaded for numerous semi-auto rifles in .223, .308, and 30.06 and never had an issue with the standard dies. The use of a small base die when you don't have to have one is said to greatly reduce the number of reloads you get from your brass due to the "work" done to the brass to resize it down to the smaller diameter (that's what the small base die does) each time you reuse it.
If someone has never had an issue they've never had to buy the small base dies.
Have a good one.
I have only encountered the problem one time in 50 years of reloading. This was fairly recently, about 8 years ago I traded for a Winchester M-70 classic in 270 Winchester. I purchased a set of dies at the same time, cleaned, sized, trimmed and loaded up a few rounds from once fired brass I picked up at the gun club rifle range.
I was pretty concerned when none of my reloads could be cambered and close the bolt.
I called RCBS and they said, oh, you have a tight chambered gun and need a SB (small base sizing die). I ordered one and received it in a couple of days. No more problems.
The factory rounds that I have checked mic. .467 +/- before it is fired and will run .468+/- after being fired in the 308LR. One Thousands growth is tight. Brass from other rifles run .468 to as much as .473 after fired. If I use the brass fired from the 308LR in my standard die it will work fine because it is already as small as the chamber it came from. When tiring to resize brass bigger then .469 in the two standard dies I have, they will not bring the brass below the .469 at the base. At .469, the brass will not feed because of the interference fit. This is also the worst case if you have a slam fire.
Using the RCBS small base dies are bring the brass back to .466 this works good. But, is hard on the brass. Annealing the brass will go along way to keeping it in good shape. If this turns out to be to hard on the brass, then I will send the dies in and have them opened up a bit.
I wasn't trying to say there was something wrong with the dies (or the rifle). Every rifle is different than the next one on the rack (or firing line). Opening up the die might get you back to the same place you were before buying the small base die.
If you are using that die to reload the brass from that rifle the "overworking the brass" comment may not apply due to the difference in your rifle's chamber. However, using the small base die to resize brass from another rifle that doesn't have as tight a chamber as your rifle might be an eventual problem.
Go slow, keep measureing and thinking (and talking to others with more experience) and you'll do alright.
Not at all M1A4ME, overworking the brass is important. I just went into more detail so some one reading the post would know the back ground and have some numbers to compare to. I also wanted to bring up the subject of annealing the brass. Another topic that a new loader may not know about.
One other topic that I have asked others is how many times they reload a single, 308 rifle brass. One can get many deference answers. I look at all my brass under magnification before and after sizing. Brass with cracks that could not be seen with the eye was found. Your right, go slow and learn.
Gentlemen,
I picked up small base dies in preparation to reloading my M4gery as that was what I had read was needed. Would you recommend I pick up a standard set to test? I don't want to shorten the life on my brass, it's too short as it is.
I have not reloaded for my CAR. My .223 reloads (standard Pacific/Hornady) dies worked great for my Ruger Mini-14.
No matter what they say about "mass production", every rifle is different than the one next to it in the rack. You won't know what your rifle "needs" till you try both kinds of dies.
As an example of the "funny" things that some folks believe are the gospel that ain't necessarily true - my M1A has a national match barrel, you know, tight chamber, minimum headspace, etc., yet I have always necksized only and my reloads for it worked great. Try different things till you find what works for you and your rifle.
usafe7ret: Yes, get standard full length dies for the brass that has only been fired in your rifle. Use SB for range pick up, then FL after first resizing. A turret press with extra turret makes this quick and easy.
A set of cartridge headspace gauges will be prudent (and irritating), so might as well get them at the same time.
http://appleseedinfo.org/smf/index.php?topic=874.0
SoM
For future reference, you MIGHT be able to get by with just standard dies, folks. Use the Small Base sizer, only if you need it, as you need it. I have both in .308 and .223, just standard for .30-06, and have no problems with my M1. Considering that I also have 2 Springfields (1903 and 03-A3), and don't keep the ammo/brass separate, that should say enough.
+1 on the case gauges. They're a good asset to check your ammo while reloading.
SoM
Read your link on the cartridge gauges ......WOW I think my head is spinning!
So's my pocket book!! But what fun!! I think ??? Standard dies & gauges to be ordered.
Well back to the bench
Nickle
Roger on the sizer die only
If you already have the Small Base SET, all you need is a regular sizer die. If you have a regular SET, all you need buy is the small base sizer die.