Std or Small Base Dies for Autoloader?

[mtgrs737]

I am looking to buy dies for M1, M1A, and 5.56mm Rifles and was wondering which type of die you folks recommend. I have always used std. sizing dies but have heard that small base dies might be better for autoloaders. Also what do you folks think about the RCBS X dies? I would like to reduce the wear and tear on my brass due to resizing.

[country gent]

Ive loaded for years with standard dies for my M1As with no concerns or problems. Both of mine are Krieger SS heavy barrels and match chambers. My Ars I use standard dies and no issues again krieger lilja barrels and match chambers. I had to face .005 off the bottoms to get headspace on sized rounds right with both calibers due to min cut chammbers. Small base dies will work brass much more than standards. A friend was using small based dies with his rifle He bought a bunch of once fired 308 ( fired in a belt feed machine gun) sizing that brass really worked him also. The handiest tool I have is a barrel stub with the neck shoulder cut in it. I can measure a fired case and get a reading to the shoulder then a sized case and besure Im pushing the shoulder back .001-.002.

[jmorris]

I own no undersized dies. If a case sized to factory dimensions will not cycle in a given firearm, I fix the firearm.

[Outpost75]

Small-base dies are not intended for semi-automatic rifles, but for pump and lever-actions such as the Savage 99 and Remington 760, which have poor chamber- camming leverage.

Their use in loading ammunition for the Garand, M14, or M1A is unecessary, and causes excessive cold working of the brass, which reduces case life.

[Bayou52]

Their use in loading ammunition for the Garand, M14, or M1A is unecessary, and causes excessive cold working of the brass, which reduces case life.

I have a M1 Garand with a brand new Criterion barrel (30-06).

Has anyone made reloads for use with one of these Garand barrels, and if so, did you use standard full length sizing dies rather than small base sizing dies?

Question - Did the standard sized casings cycle well in this Criterion Garand barrel or were there any cycling issues?

Bayou52

[USMC87]

I use only standard full length dies for autos and never had a problem.

[country gent]

SO a fired case that measures "0" on a Mo's headspace gage needs fixed? Barrel was chambered to my go gage and bolt closed with light finger peresure. Sized cases were coming out at +.001

[Reverend Recoil]

I use standard dies for my M1 and AR15 service rifles. My M1 has a new CMP Criterian barrel and will clean the 200yd SR target. There are no cycling problems. Last week I won a gold medal with this rifle at the John C Garand Match at Camp Perry. Load: Speer 125gr TNT bullets, 49.0gr IMR 4064.

[Bayou52]

Thanks for the info, Rev. Recoil, on your use of standard dies with the Criterion barrel.

And congrats on winning that gold medal at the Camp Perry match.

Bayou52

[Lloyd Smale]

I use small base dies on all my ar loading in 223 and 308. I figure the extra 40 bucks for a die set is cheap insurance to make sure ALL my ammo runs in ALL my guns. I have ars that need them and ars that dont but dont want to have to have seperate ammo. I also feel that small base sizing and trimming after everyshot is insurance that guns that may be called apon to defend my family go bang EVERY time. Ive seen no differnce in accuracy using them. Brass life differnce if any is so small i cant tell. Bottom line is i see benifits but not one reason not to.

[Lloyd Smale]

I have 7 ars. Its a heck of alot cheaper to just buy a set of sb dies then rechamber guns that dont need it.

[Lloyd Smale]

Id like to see something in print to back up that statement. Id bet 80 percent of the small base dies sold are used in the 223 and 308 for semi auto ammo. Do a search for small base dies and see what every description you find says.
Small-base dies are not intended for semi-automatic rifles, but for pump and lever-actions such as the Savage 99 and Remington 760, which have poor chamber- camming leverage.

Their use in loading ammunition for the Garand, M14, or M1A is unecessary, and causes excessive cold working of the brass, which reduces case life.

[historicfirearms]

I've got a set of 223 X dies. I like them because after the first trimming, you don't have to trim anymore. It does become a little more work to keep brass separated for another step, but the x dies save a lot of time trimming and chamfering.

Like Lloyd, I think the small base dies are valuable for semi autos. I've got a brand new AR10, and the standard lee dies wouldn't size military brass down enough to chamber. Nothing wrong with the rifle, but most 308 milsurp brass was machine gun fired in guns with very generous chambers.

[jmorris]

Bottom line is i see benifits buy not one reason not to.

Only negative I see is that you own a gun in a common chambering that will only use special undersized ammo.

[mtgrs737]

How much smaller do the small base dies size the base than regular dies? I have heard that it is only .001" but I have no experience myself in this area. I am wanting to buy some x-dies in .223, 308, and 30-06 but can't find any one place that has them all in stock.

[Rattlesnake Charlie]

Start with some standard dies borrowed from a buddy. If there is a problem with any of your firearms, you can then consider fixing the gun or getting small base dies. I've never needed them. Did start with RCBS small base dies in .308 Win for a Savage 99 because that is what RCBS chart called for. Turned out, it was not needed, and even had to go to standard size as the small base was really oversizing the case, Like could barely get it done with RCBS Rockchucker Jr.

[jmorris]

How much smaller do the small base dies size the base than regular dies? I have heard that it is only .001" but I have no experience myself in this area.

I don't either but I bet the tolerance on the dies is more than .001".

This is an interesting read.
http://riflemansjournal.blogspot.com/2010/06/basics-resizing-case-dimension-changes.html

[felix]

Wanna' be 100 percent reliable or darn close to it? You need a sloppy gun. The AK47 my sons had shot over 5000 rounds with zero hiccups. Charging beer cans were extremely nervous but never really worried about being hit at ranges 20-100 yards. For me, give me a gun with having bare minimum tolerance using custom ammo. This means custom dies without exception for my level of fun. I like to play sniper 90 percent of the time when I go shooting anymore. ... felix

[fredj338]

How much smaller do the small base dies size the base than regular dies? I have heard that it is only .001" but I have no experience myself in this area. I am wanting to buy some x-dies in .223, 308, and 30-06 but can't find any one place that has them all in stock.

That is about right, it's a small amount. I look at SB dies as insurance, especially when using mixed brass. So I have them for my AR & M1. The SB die was designed for auto, lever & pump because none of them have strong camming action.
AS to the 'X' die. I have one for the 223 & like it. In a test run of 20 cases, I reloaded them 7x w/o any measurable stretch. I then started losing some to neck/shoulder splits. I attribute that to harder mils spec brass. If it saves me from trimming more than once, I am fine with that.

[myg30]

I used the X dies in 223. I was a little un sure about trimming the brass so much shorter[.030 ?] and have to do the sizing twice the first time. I've not reloaded the brass a second time yet but from all the feed back they seem to work good. I try to keep the shorter brass separate and not mix it with factory length brass. It all cycled in my mini with no trouble.

Mike

[EddieNFL]

Loading for ARs since the late '70s. Lost track of haw many different rifles and barrels. Haven't need an SB, yet.

[FLINTNFIRE]

Never needed a small base for any of my autoloaders , but a bolt action 300mag. mark x had to use the small base rcbs dies as the full length would not chamber , factory would fit and the small base resized would fit .

[geargnasher]

I am looking to buy dies for M1, M1A, and 5.56mm Rifles and was wondering which type of die you folks recommend. I have always used std. sizing dies but have heard that small base dies might be better for autoloaders. Also what do you folks think about the RCBS X dies? I would like to reduce the wear and tear on my brass due to resizing.

I recommend good quality, standard dies. IF, and that's a very weak IF, you need them, it will likely only be for the 5.56 and only then for fixing bulged heads on machine gun brass. If standard dies won't do that, the brass may worthless anyway, or the standard dies not made correctly. The M1 and M1A have been gobbling up handloads for generations now using lowly "standard" dies. With regard for cast boolits, the more closely the brass fits the chamber, especially the head-end, the more potentially accurate the gun will be.

Gear

[winelover]

Been using X-Dies since they became available. Work as advertised. Especially good for calibers that tend to stretch after a few loadings. The 243 Winchester, comes to mind. Not necessary, for the 270W.

Winelover

[BrassMagnet]

Small-base dies are not intended for semi-automatic rifles, but for pump and lever-actions such as the Savage 99 and Remington 760, which have poor chamber- camming leverage.

Their use in loading ammunition for the Garand, M14, or M1A is unecessary, and causes excessive cold working of the brass, which reduces case life.

I guess it is time for my 2 cents worth on this.
I believe most of you are missing the boat on this. So I will divide my answer into multiple parts and try to cover all of the issues. There are many issues here.
Tolerances on machining reloading dies vary. Most FL dies are made within specifications, but could be near maximum size. SB dies are supposed to be at or near minimum dimensions. I also have "BAR" dies for "Browning Automatic Rifles" which I assume to be an early marking for SB dies.
I have had experiences with dies and molds which were not properly machined and can not make ammo within specifications. The molds must be replaced. Maybe the dies can be adjusted to work and maybe they need to be replaced.
When shooting a semiautomatic, cartridge fit is critical. Under sized cases can fail to function. Over sized cases can jam the action, crack the receiver, or even slam fire. Primers which are not seated below flush are likely to slam fire, as are sensitive primers.
Use a cartridge case gauge to adjust your reloading dies for proper dimensions. This is important and not too expensive! Don't skip it! A bolt action rifle can force an over length cartridge to chamber without harming the rifle. Slam enough of them into a Garand or M1A and you will crack your receiver in two.
Use an appropriate powder for your load! Bolt action load data is not appropriate for a semiautomatic, gas operated firearm. There must be enough, and not too much, gas pressure when the bullet reaches the gas port for the action to function properly. An inappropriate powder can be made to work, but at a cost of slamming the action harder than it is intended and greatly shortening the actions life.
Use load data tested in that type of firearm or GI load duplication data. Use a cartridge case gauge to adjust the dies. Ensure every primer is seated flush, or below, and that the primer is approved for service rifle use.
If you need load data which shows appropriate powders, I have printed sheets of load data which show military duplication loads and match loads. My sheets also show where the load data came from. It is old enough that it was printed on a Commodore 64 computer. As always, verify data against a load manual before trying it!

BrassMagnet

[Bayou52]

Turned out, it was not needed, and even had to go to standard size as the small base was really oversizing the case

That's interesting.

I just returned a FL SB 30-06 sizer die to RCBS as it was OVERSIZING the brass as compared to the standard die.

Also, I sent in some cases as well so they can check the specs on the die. I'm awaiting their response now.

Bayou52

[W.R.Buchanan]

I was told by a Factory Rep at the SHOT Show that the design for SB dies was .001-.003 under the standard minimum, however the tolerance for the operation was +/-.003. Which means a SB die can actually be larger than a normal die cut at the low end!

I looked at the guy and said "REALLY?"

He laughed.

I personally don't see a reason for SB sizing dies. It would take extraordinary circumstances for a gun to not chamber a normally loaded round, and as stated above, maybe the gun needs attention. Making specialty ammo for high volume usage is kind of counter productive. The only reason for these after hearing the reps response was that RCBS needed another product to sell, and there was some market for it.


HOT TIP! When sizing machine gun cases for the first time, first lube them with Dillon case lube or other spray lube thoroughly.

Then run them into the sizing die just past where they start to get hard to push in. Remove and then repeat.

It will go much smoother since you are not doing all the work in a single pass.

I have been using an X die to size all my .308 brass for my Gunsite Carbine. I trimmed them once short and have not had to do it again. I think for brass that you will load many times the X die is a good investment. However your regular sizing die should be used the first time you size the brass just so you are not trying to size large cases in the X die.

I will do the X die for .30-06 cases for my guns Springfield and Garand, but I think it is pointless for the .223's since they are never easy to find and nearly impossible to keep separate from previously X-died brass. IF you can then What the hey? it can't hurt.


Randy

[Bayou52]

I was told by a Factory Rep at the SHOT Show that the design for SB dies was .001-.003 under the standard minimum, however the tolerance for the operation was +/-.003. Which means a SB die can actually be larger than a normal die......

That's interesting to learn. I'll be soon speaking with a RCBS factory rep as to why my SB die is oversizing, as I've returned it to them already. I suspect he'll say just what you've said. I'll ask them to replace this die.

Bayou52

[DaveInFloweryBranchGA]

Years ago, I had an AR15 rifle that had problems chambering. I was to the point of actually thinking about buying a small base die and did. But after a long discussion with some old heads on this forum, I decided to follow their advice and give my standard die one more try. I did what they told me to and turned my standard die a bit more snugly into the press, making it size a bit more. Low and behold, my brass got right and started chambering. Turned out I wasn't adjusting the die quite right on that particular progressive press and tolerances had back up enough with "give" to cause chambering issues. Simply snugging up the die addressed the issue.

Here's my suggestion: 1. Instead of buying a set of small base dies, buy a Dillon or Wilson brand case gauge for the cartridge you are reloading. 2. Adjust your standard dies until your case measures properly in the case gauge. 3. Reload cartridges for your semi autos to your heart's content, having found that measuring/gauging your brass is the best approach.

BTW, I follow my own advice on every single semi auto I own. I haven't had a problem reloading for any semi auto since I started following my own advice above and I'd only had the one problem before.

So spend your money on a case gauge, not small base dies.

[Lloyd Smale]

dave the problem with your fix is that if your using once fired brass that may have been fired in a larger chamber by the time you ajust your die down to where it will size the base enought to function your pushing the shoulder back to far. I just cant figure why some of you are so adimately against sb dies. Ive tested rounds in my ars using both and have seen no differnce in accuracy and very little if any differnce in brass life. Standard dies are just fine if you have ONE gun and the chamber is cut generously enough for function and you plan to start with new brass. But in ars i go though lots of brass and just the fact I can buy once fired brass fired in about anything and make it work more then has paid for my sb die sets. Just the peace of mind of knowing there going to function a 100 percent makes it worth while to me to size sb and trim after every shooting in my ar loading. Id bet some of you that are against it are actually doing it and dont know it. Dillon and redding dies for the 223 are cut to small base dimentions.

[Lead Fred]

I have two friends that have 1950s remmy pumps, they HAVE to use small base dies.
They sizer die is .003 tighter than the std, and .001 less than my pro black set.

Being my M1 is match grade, I considered trying SB dies, just have not gotten around to it.

My bud uses them for his AR, & M1a. He has has sticky cases, it cured that.

[W.R.Buchanan]

Lloyd: I am not adamantly against SB dies. However they are a solution to a problem that I don't have.

In the vast majority of cases regular dies are fine.

If you experience a tight chamber SB dies might be the cost effective solution.

Just using them just because you "think" you need them is counter productive. IF the gun doesn't eject cases right it may need the chamber polished, and this is common with re-barreled Garands. If the gun won't feed factory rounds into the hole and close the bolt then the first place to look is the chamber itself.

If it won't feed your reloads into the chamber and close the bolt, then the first place to look is the sizing die.

If you are getting all you can out of the sizing die and the gun will go into battery with the chamber gages, then that die is not doing its job.

AS you know .30-06, .308, and .223 chamber gages IE; "Go gages" are available in .001 increments thru the .010 range of the go gages. This helps you discern exactly what you've got in the way of chamber tightness. IF the .001 over minimum gage is the only one that chambers, and this is not your target rifle, you may want to open things up a bit.

In a gun with a tight chamber that is used for target shooting small based dies may be a appropriate solution to feeding problems.

For a defensive gun, factory ammo should be the baseline test, if it won't run with factory ammo, there is definitely a problem with the gun.

IF it does run, then you should do everything possible to duplicate those round's dimensions in your reloads.

This can normally be done with normal sizing dies. There may be exceptions.

Accurately diagnosing the exact problem, is the key to fixing any problem.

Our government is a perfect example of those who don't do this well, and we see this everyday as problems spiral out of control.

Randy

[ROGER4314]

I shot NRA 200-600 yard matches with the AR-15, M1 Garand and M1A and used SB dies. I didn't care if the brass was worked more and was willing to reduce the life of my brass to ensure proper function. In nearly eight years of matches, I never had ONE single malfunction with the semi auto rifles! NOT ONE!

In bolt matches, my 1903A3 had a nasty habit of misfiring in rapid fire stages if I failed to return the bolt to fully down position. That was NOT the fault of the rifle......I was in a hurry. Another time, I had the 1903A3 stock/action mounting bolts come loose and the rifle developed a mind of its own. After that, I checked torque on those bolts before every bolt match.....with a torque wrench!

Flash

[Lloyd Smale]

I agree roger and would about bet a dime to a dollar that alot of the guys that are saying there not needed have at one time had a failure to feed and smacked there forward assist. Most blame it on a dirty gun or just think that it just happens occasionaly with an ar. Like i said in a previous post my ars might be called on to defend my family or maybe yours and i want them to go bang EVERYTIME i pull the trigger. One failure in even a 1000 shots is not exceptable so ill continue my routine of sb sizing and trimming after every firing. I know that way that my ammo is reliable and is going to fit in any gun i put it in. Like i said i see absolutely no reason not to other then the price of a set of dies. Ive seen no differnce in accuracy and the small amount more your sizing brass isnt going to effect brass life, at least not that i can detect, and it doesnt make loading any harder or slower.
I shot NRA 200-600 yard matches with the AR-15, M1 Garand and M1A and used SB dies. I didn't care if the brass was worked more and was willing to reduce the life of my brass to ensure proper function. In nearly eight years of matches, I never had ONE single malfunction with the semi auto rifles! NOT ONE!

In bolt matches, my 1903A3 had a nasty habit of misfiring in rapid fire stages if I failed to return the bolt to fully down position. That was NOT the fault of the rifle......I was in a hurry. Another time, I had the 1903A3 stock/action mounting bolts come loose and the rifle developed a mind of its own. After that, I checked torque on those bolts before every bolt match.....with a torque wrench!

Flash

[ROGER4314]

The small base dies offer you a slight advantage in reliability but it's like glass bedding a rifle action. Some say that a match rifle MUST be glass bedded to shoot competitively. That's total hogwash! Items like glass bedding may ad a point or two to your score. NM sights may add a point or two more but the rifle will shoot just fine without bedding or a full float tube on an AR-15. In fact, I quit worrying about such things and concentrated on making ME a better marksman. I have the awards to show that it was a good decision!

Small base dies give you a tiny edge in function. Is it a lot? NO! I've seen many malfunctions on the match firing line. I'll list a few. I stress that these were not MY malfunctions but I was there to witness them:

AR-15 misfire- Primer installed upside down. Poor QC on reloading. Lost a stage score.
AR 15 charging handle broken. Hooked end snapped off. Probably due to clearing a previous jam. Allowed to reshoot after repair.
AR-15 action wouldn't function in rapid fire stages. Untested ammo (Wolf). Underpowered ammo. We voted and allowed him to single load to finish the match. Came to the line with unknown ammo. Bad plan!
AR-15 brought wrong ammo to the line. He beat himself! He is a "High Master" shooter, too!
AR-15 Incomplete gun. Left the carrier and bolt group at home. Again, he beat himself!

Those are the ones that stick in my memory. In every case, close inspection would have kept the shooter in the match. SB dies give me just a shred of advantage in a match and that's why I used them for my competitive match ammo.

OH....I also check every round for proper primer installation and use a piece of glass to check for "rockers" (high primers). On a load that I can hear the powder, every round is shaken before it gets loaded into a magazine. Sometimes, I weigh them to make sure each has powder. If you don't do those things, YOU BEAT YOURSELF!

Flash

[W.R.Buchanan]

My hi volume shooting is at Rifle classes at Front Sight. Typically 400 rounds over 4 days. WE see every kind of service rifle known to man, and there is usually 60 people in every class. That's 24-25,000 rounds fired in one class. The vast majority of guns used are AR15's of one type or another.

Everyone is REQUIRED to use Factory New Ammunition. No exceptions. And no steel bullets are allowed either which eliminated most to the Russian ammo which can be problematic.

Malfunctions are common, and the reasons are pretty diverse, and ammo is almost never the cause.

I have seen a few new factory brand name ammo rounds with primers upside down, This is pretty rare.

However most FTF's are as a result of the bolt not being completely in battery. And this is common with AR type guns. In all of the cases I am siting the ammo was not the problem since it was factory new ammo. Dry guns, bad magazines and dirty guns are the biggest problems. Failures to eject are common and are the product of worn or bad extractors or bolts not being completely in battery, and this usually occurs as a result of "chamber checking" and failing to reseat the bolt afterwards. Note the button on the right side of the receiver called a "Forward assist" specifically used to avoid this problem. However it must actually be used to be effective. Again not an ammo related failure, simply operator error.

My point is that 99% of FTF's are the operators fault,,, not the ammo. Just learning to efficiently clear malfunctions trumps relying on the quality of your ammo to keep you running. You need both and neither is an end all.

Factory new ammo is the standard we judge all other ammo by, and if you can duplicate the size of those rounds then you should be just fine.

Another way to see if you are good is to buy a Wilson Case Gage for your caliber and run all your reloaded ammo thru that. If it fits in the gage it will fit your chamber,,,, unless there is something wrong with your chamber. This doesn't sound like it would be too big a deal to do if you are looking for 100% reliability. I know plenty of competition shooters who shoot reloads in their guns exclusively and I even know some who check every stinking round thru a case gage. Way too much for me, but if it makes them have a higher degree of confidence then What the hey?

Small based dies have only been produced in the last few years (<10) and only RCBS makes them. Why aren't the other die makers producing them?

How did we ever live without them?

The beauty of this country is that you can do pretty much whatever you want. I choose not to use this product simply because I don't see a valid reason for doing it. I think I have made a pretty good case for my stance on this subject.

YMMV.

Randy