I've been in the process of prepping a couple thousand 5.56 Lake City brass cases. I've already sized them all after setting up dies using a headspace gage. I'm at the trimming stage now and decided to check all cases again in the headspace gage. Lo and behold, a little more than 1% of them did not fit. I was baffled until I decided to try inserting them base first into the headspace gage. And that was where the problem was. The bases were too fat to go in. Is this where a small base die would come in handy? I've just recently returned to reloading after more than a decade and don't remember ever having this problem before with regular FL dies.
Small base dies for once-fired mil brass
- Thread starter satexas
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dh1633pm
Contributing Member
Yes, that is the purpose of the small base die.
243winxb
Member
Could be a burr on the rim from the extractor keeping it from going into the gage.
Ironicaintit
Member
243winxb said:
satexas said:
Not to try and be redundant, or belabor a point, but...
I'd double check and see if there is a burr present at the rim. It doesn't take much of a scuff to keep it from seating in the gauge.
With both 308 and 223, even with cases shot in pretty loose chambers and hot loads: the only reason I've ever had one not fit the gauge was because of a burr, and I only use a plain ol' FL die.
Gentlemen, I stand corrected. 243winxb and Ironicaintit were spot on. I examined the cases and found they did indeed have burrs from extraction. I took a small fine file to the burrs, and they now fit! Thanks guys! You saved me the expense of buying a small base die!
jwrowland77
Member
Ummm, did you try it in your rifle?
I use 5.56 LC brass for my match loads and use a Redding body die. I've never used a SB die or a case gauge. I always test the cases in the firearm they're to be used in. I figure I spent several hundred dollars on a case gauge that also fires completed rounds, might as well use it.
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I use 5.56 LC brass for my match loads and use a Redding body die. I've never used a SB die or a case gauge. I always test the cases in the firearm they're to be used in. I figure I spent several hundred dollars on a case gauge that also fires completed rounds, might as well use it.
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No, I haven't tried to fit the cases in my rifles. I'm assuming (bad word...bad bad bad), that since the cases fit between the min and max planes of the headspace gage, that they should fit in any rifle. These will be shot out of any of my AR-15s, and I'm not loading for precision.
waffentomas
Member
Don't need a SB die in a military type semi. Their chambers are roomy. SB dies meant for tight match chambers in .223 bolts. Those burrs, and this forum saved you $50. Go buy ammo!
I would try them in your rifle. Just because they fit your gage does not mean they'll fit our rifle. You may or may not need small base dies. The correct answer is it depends. Use a case gage to make sure your headspace is proper and check your rifle with your reloads. I sized a couple hundred once and assumed they fit since they passed the gage. They didn't and I got to size them all again.
-jeff
Whenever there is a fit problem, measure. Measure one of the offending rounds, the diameter in a few places along the case. Measure the rim diameter and check for bends or burrs. Compare your measurements with SAAMI specs. I would rather know for sure, what size a cartridge is, than if it goes or doesn't in a "gauge"...
Ok guys, I took one of the cases and it fit nicely in my rifle. All it was, was just burrs on the rims from extraction. I really appreciate all the responses, plus I feel better actually knowing they fit in my chamber! And, I saved 50 clams!
Nature Boy
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Glad you figured it out. I realized it also doesn't take much build up of case lube in the gauge to cause your brass to show being out of spec. Drove me nuts during my very first loading session. Even called Dillon thinking I wasn't resizing my brass correctly. Dillion guy clued me to clean the gauge and try again. Sure enough
By the way (just for laughs) RCBS says their small base die will size the body (NOT THE BASE) down a few thousands tighter than a standard full length die. And it will bump the shoulder back a few thousandths shorter than a standard full length die.
http://www.rcbs.com/Products/Dies-b...-Sizer-Die-Group-D-Bottleneck-Rifle-Cart.aspx
But those dies only affect the shoulder and body, they don't touch the base and rim. So if the base and rim were satexas problems, he would have wasted his 50 clams anyway.
If you read some posts, the guys swear that if you don't use Small Base for an AR rifle the sun will fail to rise, the birds will fail to sing, and bears will come down from the woods to eat you. Maybe because they see "Small Base" and they think that refers to the cartridge base. No, it's a manufacturing term.
In a machine tool company, small base means reducing setup dimensions on the mills and lathes making the product. [For instance, setting up to make Small Base Camshafts for a race car engine so the lobe lift can be higher.] To make dies that reduce shoulder and body by .003", they simple use a "small base" setup on their tooling. So the manufacturers started calling those dies Small Base. It has nothing to do with the base of the cartridge case. It's the machine tool setup.
http://www.rcbs.com/Products/Dies-b...-Sizer-Die-Group-D-Bottleneck-Rifle-Cart.aspx
But those dies only affect the shoulder and body, they don't touch the base and rim. So if the base and rim were satexas problems, he would have wasted his 50 clams anyway.
If you read some posts, the guys swear that if you don't use Small Base for an AR rifle the sun will fail to rise, the birds will fail to sing, and bears will come down from the woods to eat you. Maybe because they see "Small Base" and they think that refers to the cartridge base. No, it's a manufacturing term.
In a machine tool company, small base means reducing setup dimensions on the mills and lathes making the product. [For instance, setting up to make Small Base Camshafts for a race car engine so the lobe lift can be higher.] To make dies that reduce shoulder and body by .003", they simple use a "small base" setup on their tooling. So the manufacturers started calling those dies Small Base. It has nothing to do with the base of the cartridge case. It's the machine tool setup.
FROGO207
Member
I just reject those into a bucket of "I'll tend to those if I ever need to use them." I have so many 223/5.56-308/7.62x51 brass that I really do not need to mess with them at the present time. I also do that with the brass that will not easily fit into the shell holder due to burrs there as well. Someday if I ever retire or get bored enough then I will get my file and go for the gold
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.FWIW and off topic; Like Frog, I have a "tend to them later box" that I "store" questionable ammo/brass, etc. Sometimes I'll run into a solution on a forum or in a book and dig out those "odd" rounds and fix 'em...
Example, I had about a hundred HXP cases that would not fit an RCBS case gauge after F/L sizing. I tried everything I could think of; measured diameter the entire length of the body and case lengths, all dimensions seemed to be in spec., re-adjusted sizing dies several times, even changed sizing dies. Only on HXP brass, not Hornady and I worked on this for several weeks (I wasn't gonna toss 100 30-06 cases!). Finally I saw/discovered a very slight bend in the case rim. Eureka! The case rim was being distorted on ejection from my Garand just enough to make the cases "stand proud" a few thousandths in my case gauge. Case gauge in now "in storage"...
Example, I had about a hundred HXP cases that would not fit an RCBS case gauge after F/L sizing. I tried everything I could think of; measured diameter the entire length of the body and case lengths, all dimensions seemed to be in spec., re-adjusted sizing dies several times, even changed sizing dies. Only on HXP brass, not Hornady and I worked on this for several weeks (I wasn't gonna toss 100 30-06 cases!). Finally I saw/discovered a very slight bend in the case rim. Eureka! The case rim was being distorted on ejection from my Garand just enough to make the cases "stand proud" a few thousandths in my case gauge. Case gauge in now "in storage"...
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tcoz
Member
If the cartridge head is the only part that protrudes from a case gauge it's almost surely burrs, dents or a slight bend in the rim. The M1 Garand is one of the worst offenders. In my experience it hasn't affected chambering or extraction unless it's really severe.
Waffentomas said it best...
"Don't need a SB die in a military type semi. Their chambers are roomy. SB dies meant for tight match chambers in .223 bolts. Those burrs, and this forum saved you $50. Go buy ammo!"
Waffentomas said it best...
"Don't need a SB die in a military type semi. Their chambers are roomy. SB dies meant for tight match chambers in .223 bolts. Those burrs, and this forum saved you $50. Go buy ammo!"
The base of the small base die will never make it to the base of the case if the base of the case is the head of the case.
My shell holders have a deck height of .125"; that means the base of the case can not be sized. If I was curious about the head of the case being upset I would turn the case around and shove it into the big end of the die.
I have cases that have been hammered with heavy loads, the heavy loads crushes the case head. Under normal conditions and factory loads the case head upsets .00025", in theory the case head would expand .001" when fired 4 times. And then there are cases that are thought to be soft.
The small base die has nothing to do with the small base of the case, the small base die is smaller in diameter at the base of the die. Then there is always that discussion about how much smaller in diameter the small base is than a standard die.
I have small base dies, my small base dies want to keep every case I shove into them. I measured them and they are smaller in diameter than small base dies.
Then then there is the M Garand, the M1 Grand shot the same ammo as the 03 and M1917, the difference between the 30/06 chamber and the M1 30/06 chamber was less than .0005". I am told the old guys could not hold tolerances that close but it is in the book.
I have an old gage that measures down to .000005", to me it was useless so I modified it to start measuring at .0005".
F. Guffey
The case gage measures fired and, new and full length sized cases, again turn the case around and place the head of the case into the case gage. Again there is no way to size the head of the case below .125" from the head of the case because of the deck height of the shell holder. Meaning if the case head will not fit the case gage the case head has been crushed/upset.
"SB dies meant for tight match chambers in .223 bolts."
RCBS doesn't know that. Go look at the RCBS web site. http://www.rcbs.com/Products/Dies-by-Category/AR/Small-Base-Taper-Crimp-Die-Set-AR-Series.aspx
This is what it says,
"RCBS® AR Series Die Sets are a must for progressive reloaders. They feature a Small Base Sizer Die designed for semi-automatic firearms, and a Taper Crimp Seater Die. The Small Base Sizer guarantees the cartridge will rechamber in AR-platform weapons."
Apparently RCBS doesn't read posts on this High Road forum, they don't know SB dies are meant for tight match chambers in .223 bots. They sell Small Base dies by the hundreds to AR owners because the Internet tells hundreds of AR owners that they must use Small Base dies. So RCBS sells them by the hundreds.
tcoz
Member
ants, I'm not sure which side of the fence you're on from your post but I definitely agree with the following statement that you made...
IMO, those of us on THR represent the most knowledgeable 5% of handloaders. The other 95% only know enough to be able to throw together some ammo that they can shoot in their guns. Conversations I've had with "reloaders" at the range are what lead me to that conclusion. The majority of them also don't know to to properly adjust a sizing die and as a result they often make ammo that won't chamber or extract. RCBS is appealing to these people by saying that their SB dies are meant for ARs and their tight chambers and will make ammo that's guaranteed to chamber. Most of us know that the AR platform isn't universally known for having tight chambers except maybe in the case of a few companies, with Noveske coming to mind.
I like RCBS and use a lot of their equipment. I think they're using a good marketing strategy with these die sets which they state are designed for semi-automatic firearms and will make cartridges guaranteed to chamber in AR platform rifles. I just don't believe that the majority of AR platform rifles need SB dies. They need owners who know how to adjust a sizing die.
Like I said though, this is just my opinion.
IMO, those of us on THR represent the most knowledgeable 5% of handloaders. The other 95% only know enough to be able to throw together some ammo that they can shoot in their guns. Conversations I've had with "reloaders" at the range are what lead me to that conclusion. The majority of them also don't know to to properly adjust a sizing die and as a result they often make ammo that won't chamber or extract. RCBS is appealing to these people by saying that their SB dies are meant for ARs and their tight chambers and will make ammo that's guaranteed to chamber. Most of us know that the AR platform isn't universally known for having tight chambers except maybe in the case of a few companies, with Noveske coming to mind.
I like RCBS and use a lot of their equipment. I think they're using a good marketing strategy with these die sets which they state are designed for semi-automatic firearms and will make cartridges guaranteed to chamber in AR platform rifles. I just don't believe that the majority of AR platform rifles need SB dies. They need owners who know how to adjust a sizing die.
Like I said though, this is just my opinion.
RecoilRob
Member
Since the conversation is about 'small-base' RCBS dies, if you're in the market for a set be sure to get the 'X' die as it really does control the stretching pretty well. Once you have all of your brass trimmed to a consistent length, you can then set the decapping/expanding rod to them as it has a shoulder that bumps the case mouth right as the case is getting fully into the die. This little bump prevents the neck from stretching more than a few thousandths so you'll likely never need to trim that case again in it's lifespan of 4 or so firings. Past that...I'd not know.
carbine85
Member
A lot of AR barrel manufacturers make tighter chambers than a "Mil Spec" chamber. SB dies may or may not be needed, it all depends on your barrel. I think Lee dies are somewhere between standard and SB.
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