22-250 small base sizing die

2

2old2run

Private
Minuteman
Oct 20, 2024
19
15
Northern Wisconsin
#1
I'm considering building an AR platform in 22-250. Looking for a small base die set and see they are no longer made by RCBS. I don't want to be married to factory ammo if I go this route. Does anyone have any experience with this type of setup? Just curious.

It would be hell if I had to go the bolt gun route, lol.
 
#3
Pick up a Lee .45ACP U-die small base sizing die and pull out the guts, voila, 22-250 (or any other .308-sized case head case) small base die (~$20).

It won't touch/bump your shoulders or necks, so you'll also/still need to use a 22-250 sizing die, but the Lee .45 U-die is just a carbide sizing die for a straight-walled pistol case, so it'll take care of the base of the cases for you.
 
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#4
CK1.0 said:
Pick up a Lee Factory Crimp Die in .45ACP and pull out the guts, voila, 22-250 (or any other .308-sized case head case) small base die (~$20).
Click to expand...

I've heard this recommendation before... I already have a 'ring' die, so I don't really need another. Just out of curiosity... what does the ID of these dies actually measure? What do the cases actually measure @ the 0.200" line coming out of one of those?
 
#5
memilanuk said:
I've heard this recommendation before... I already have a 'ring' die, so I don't really need another. Just out of curiosity... what does the ID of these dies actually measure? What do the cases actually measure @ the 0.200" line coming out of one of those?
Click to expand...

I actually edited my post while you were typing... I misspoke, it's the .45ACP U-die small base sizing die (NOT the Lee FCD) that does the trick. IDK what the ID is exactly, but it works. A .45ACP case OD is .476", using the U-die (-.003") you get .473" (same as a .308).

www.midwayusa.com

Lee Undersize Carbide 45 GAP, 45 ACP Small Base Sizing Die

Lee U Carbide Undersized Sizing Dies are great for reloaders looking for ultimate feeding reliability in their handgun. These dies undersize brass...
www.midwayusa.com www.midwayusa.com
 
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#6
Then I don't see how that would actually work, in practice.

Most of my 'direct' experience is with .308 Win, as that's what I shoot in F-TR. Somewhere a few tenths north of 0.471" is where things start getting 'sticky'. Most small base dies squarsh it down to somewhere in the low 0.470 range. My 'ring' die is set for a 0.468" ID, which between spring back and whatnot, usually yields something in the range of 0.469" at the 0.200" line - and pretty much all the way to the extractor groove.

0.473" ain't gonna do it.
 
#7
memilanuk said:
Then I don't see how that would actually work, in practice.

Most of my 'direct' experience is with .308 Win, as that's what I shoot in F-TR. Somewhere a few tenths north of 0.471" is where things start getting 'sticky'. Most small base dies squarsh it down to somewhere in the low 0.470 range. My 'ring' die is set for a 0.468" ID, which between spring back and whatnot, usually yields something in the range of 0.469" at the 0.200" line - and pretty much all the way to the extractor groove.

0.473" ain't gonna do it.
Click to expand...

IDK, YMMV. I had a buddy having trouble with a new 6CM gasser and the U-die did the trick (I can't remember what the before/after measurements were, sorry).

For ~$20, it's worth a try...
 
#9
I see they still do. I was under the assumption that they were to minimize trimming. I do have x dies in several other calibers, but they also are specific as being small base.

I was mainly looking for a shooter. And ran across the 22-250 upper from Bear Creek Arsenal. After doing some reading about these, I'm reluctant to pursue.

I put a Howa together about 8 years ago in 223 remington, using a boyds stock. It was a good shooter on prairie dogs in south Dakota. Might just try that again in 22-250.
 
#10
I never needed a small base sizing die to run any 308, 6.5 CM, or 300 Ruger Compact Magnum, even with the max loads I run in the AR 10. Just regular FL dies work fine for a variety of autos, barrel lengths very firm 16" to 24" with most 18".
Many utilize the 6.5CM small firing pin dual ejector called "high pressure bolt".
One even has a magnesium upper with a titanium carrier, I just use regular sizing dies.
Try them first to see if ya even have a problem.
 
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#11
Use standard dies and if they don’t size the base small enough for your chamber then use a 308 small base die with the guts removed in conjunction with your 22-250 dies. My RCBS small base 308 die will get the bases down to .468”.
 
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#12
In reality it's not as it appears.
Most of the solid head portion of the case is not touched by any sizing die.
Because you have a shell holder and its thickness plus the lead in radius or champher on the die.
Mostly one sizes the portion just above the sold head where the real case expansion takes place.
Then part of the solid head is not supported by steel of the chamber.
If it expands the primer falls out.
You can not size what your die can not reach.
And you definitely are not reaching into the solid head
1 st pic 308 factory win chamber, notice there is no support over most of the solid head portion of the case. It could be .480" here and still chamber ...only the bolt .480 diameter goes over this portion of the .470" case head. If it expands .001" or .0015 " here your primer falls out.
The expansion mainly takes place above the solid case head where brass is thin.
Next pic here are some modified dies to make 308 into 35 Rem.
The shell holder is thinned and under cut to accept the thin silver brazed carbide ring extending from the special die. All undercut to fit inside the shell holder.
NOTICE when fully in max sizing position it still does not size maybe .030" of the solid case head. So its put in a lathe collet and turned down to size, as the case rim has to be cut down anyway.
So your factory dies do not even come close to fully sizing the solid head.

Next pic, this it the home built die to fully size the whole case...notice it meets resistance where most sizing dies do their work...this ia a real full length case sizing die...the whole case solid head and all, but does not touch the shoulder and neck.
You do not do this on a reloading press, but an arbor press.
Lube and size like using a bullet sizer.

These sizing problems are a mismatch between the rifles chamber and full length die, with tolerance stack up between the two, surface finishes, etc and even differences in brass cases and their hardness. I have a bunch of different 308 dies, maybe 8, each sizes a bit different. None are small base, but one Hornady die in particular oversizes the brass, but it does not reduce the solid head dia because it can not reach it...as shown.
 

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#13
45-90 said:
In reality it's not as it appears.
Most of the solid head portion of the case is not touched by any sizing die.
Because you have a shell holder and its thickness plus the lead in radius or champher on the die.
Mostly one sizes the portion just above the sold head where the real case expansion takes place.
Then part of the solid head is not supported by steel of the chamber.
If it expands the primer falls out.
You can not size what your die can not reach.
And you definitely are not reaching into the solid head
1 st pic 308 factory win chamber, notice there is no support over most of the solid head portion of the case. It could be .480" here and still chamber ...only the bolt .480 diameter goes over this portion of the .470" case head. If it expands .001" or .0015 " here your primer falls out.
The expansion mainly takes place above the solid case head where brass is thin.
Next pic here are some modified dies to make 308 into 35 Rem.
The shell holder is thinned and under cut to accept the thin silver brazed carbide ring extending from the special die. All undercut to fit inside the shell holder.
NOTICE when fully in max sizing position it still does not size maybe .030" of the solid case head. So its put in a lathe collet and turned down to size, as the case rim has to be cut down anyway.
So your factory dies do not even come close to fully sizing the solid head.

Next pic, this it the home built die to fully size the whole case...notice it meets resistance where most sizing dies do their work...this ia a real full length case sizing die...the whole case solid head and all, but does not touch the shoulder and neck.
You do not do this on a reloading press, but an arbor press.
Lube and size like using a bullet sizer.

These sizing problems are a mismatch between the rifles chamber and full length die, with tolerance stack up between the two, surface finishes, etc and even differences in brass cases and their hardness. I have a bunch of different 308 dies, maybe 8, each sizes a bit different. None are small base, but one Hornady die in particular oversizes the brass, but it does not reduce the solid head dia because it can not reach it...as shown.
Click to expand...
Appreciate all of your info and time!
 
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#14
I am late for the train, again.
Before you chamber your rifle, why do you think you will need a small base die?
My reamers are minimum SAAMI spec, and standard dies work fine.
Before you order the chamber, check the dimens. So called "match" chamber might be undersized without benefit.
The only time I tried a small base die, it shaved brass off the case.
 
#16
My RCBS SB die sizes all cases down to .467-468” except Winchester because they are .464” in diameter most of the time. You can easily tell the die sized all the way down to the extractor groove. In fact, it has trouble sizing Starline brass because the solid part of the case head is too big in diameter. I end up with a slight lip just north of the extractor groove.

The standard FL die may or may not size all the way down depending on the make of die and make of brass. But small base dies size pretty tight. I have several.
 
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#17
918v said:
My RCBS SB die sizes all cases down to .467-468” except Winchester because they are .464” in diameter most of the time. You can easily tell the die sized all the way down to the extractor groove. In fact, it has trouble sizing Starline brass because the solid part of the case head is too big in diameter. I end up with a slight lip just north of the extractor groove.

The standard FL die may or may not size all the way down depending on the make of die and make of brass. But small base dies size pretty tight. I have several.
Click to expand...
You are 100% WRONG. The FL die can NOT physically size down to the extractor groove.
Here is a 308 case sized down to .450" with a special ground sharp radius carbide die all the way down to touch the shell holder...a bit of brass is shaved off the head...but it stops short of the extractor groove by quite a margin.

.450" from ..4685"...this would Definitely would be a considered a small base die and undersized for a 308 case head.

But it doesn't size all the way down to the rim extractor groove...as you claim ...because it can not.

The shell holder and the lead in radius of your die cause this to be even more exaggerated on store bought dies.

I even cut shell holders down to the bare minimum, until they barely hold the case, and tiny radius on the dies to get farther down the case head, when forming 308 to other calibers.

Measuring over the unsized portion of the 308 case head, down there it's still about .4685 "in its orginial fired form.

When the solid head expands just a bit your primers pockets get loose or the primer falls out.

There is no argument here ...just the facts.

If you were into case forming, making dies, cutting extractor grooves, like forming 35 Rem from 308 cases you might have a clue.
Your lack of knowledge in this matter is astounding... so here is your a brief education.
 

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#18
45-90 said:
You are 100% WRONG. The FL die can NOT physically size down to the extractor groove.
Here is a 308 case sized down to .450" with a special ground sharp radius carbide die all the way down to touch the shell holder...a bit of brass is shaved off the head...but it stops short of the extractor groove by quite a margin.

.450" from ..4685"...this would Definitely would be a considered a small base die and undersized for a 308 case head.

But it doesn't size all the way down to the rim extractor groove...as you claim ...because it can not.

The shell holder and the lead in radius of your die cause this to be even more exaggerated on store bought dies.

I even cut shell holders down to the bare minimum, until they barely hold the case, and tiny radius on the dies to get farther down the case head, when forming 308 to other calibers.

Measuring over the unsized portion of the 308 case head, down there it's still about .4685 "in its orginial fired form.

When the solid head expands just a bit your primers pockets get loose or the primer falls out.

There is no argument here ...just the facts.

If you were into case forming, making dies, cutting extractor grooves, like forming 35 Rem from 308 cases you might have a clue.
Your lack of knowledge in this matter is astounding... so here is your a brief education.
Click to expand...

You are incorrect
 
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#22
918v said:
Clearly the die sized the case all the way to the extractor groove.
Click to expand...
No, clearly it does not...you are wrong again, and here's why...garbage in garbage out. You clearly do not know whats going on.

You are sizing the bulge not clear to the extractor groove.

Get a blade Mike or sometines cut the rim dia down in a lathe ...

Here ya go

Fired case measure over the head with your micrometer you will get off the solid head and on to the body where the largest expansion takes place between the solid head and the body juncture.
You run your die down to the bottom and only reach a portion of the solid head, so it does not size there.
The hot loaded 6.5 CM bulged at and ahead of the solid head...
This case has the rim turned down so it does not interfere with the measurement...some rims are smaller dia so as not to interfere with your measurement.
The solid head has only expanded .0007" to .0008" indicating close to max load, as .001" expansion here starts having short primer pocket life.
But above that more expansion occurred and that is what your sizing die sizes..the high point bulge...mine sets the bulge back about .0005" to 0006" from fired dia and does not touch the solid head.

You can actually see where the FL die stops.. .a long way from sizing all the way to the rim....seriously.

Also hold the micrometer and case into the light ...look at the micrometer anvils and see the light shining through near the rim ..
It's smaller there cause it's the solid head and didn't expand as much as the bullge which is what you are sizing...only a small portion of the solid head is touched.

Another example hybrid stainless steel case heads fired near 80,000 psi in 6.5 C M, any standard FL die can be used... you only size the expanded brass... not the stsinless steel case heads.
...But there is no need to be concerned they are .469" after firing 54 grains of powder behind a 150 gr bullet in a 308 and only the brass portion needs to be resized...
 

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#23
918v said:
Clearly the die sized the case all the way to the extractor groove.
Click to expand...
No it does not...
You are sizing the bulge not clear to the extractor groove.

Get a blade Mike or cut the rim down in a lathe ...

Here ya go

Fired case measure over the head with your micrometer you will get off the solid head and on to the body where the largest expansion takes place between the solid head and the body juncture.
You run your die down to the bottom and only reach a portion of the solid head, so it does not size there.
The hot loaded 6.5 CM bulged at and ahead of the solid head...
This case has the rim turned down so it does not interfere with the measurement...some rims are smaller dia so as not to interfere with your measurement.
The solid head has only expanded .0007" to .0008" indicating close to max load, as .001" expansion here starts having short primer pocket life.
But above that more expansion occurred and that is what your sizing die sizes..the high point bulge...mine sets the bulge back about .0005" to 0006" from fired dia and does not touch the solid head.

You can actually see where the FL die stops.. .a long way from sizing all the way to the rim....seriously....look at the case the difference in color and vertical scratches of the die...plus fires rounds from the chamber...see where the bulge is...not on the solid case head but just before it.

Also hold the micrometer and case into the light ...look at the micrometer anvils and see the light shining through near the rim ..
It's smaller there cause it's the solid head and didn't expand as much as the bullge which is what you are sizing...only a small portion of the solid head is touched.

Another example hybrid stainless steel case heads fired near 80,000 psi in 6.5 C M, any standard FL die can be used... you only size the expanded brass... not the stsinless steel case heads.
...But there is no need to be concerned they are .469" after firing 54 grains of powder behind a 150 gr bullet in a 308 and only the brass portion needs to be resized...

Another example... a homework assignment.
Check into the Glock bulge any why it's hard to size that far down with conventional dies ...and roll sizing the 9 mm. Might have something to do with the unsupported Glock chamber and +p loads, and the conventional shell holder and dies can not reach all the way down to the rim when sizing.... a whole new industry has been created to solve the problem.

One can learn something new every day...if ya want to...or be wilfully stubborn and wrong.
 
#29
Yes the die sizes the bulge ...not all the way down to the rim.

If you'd measure it correctly...but you do not, and continue to propagate your false narrative of sizing all the way to the rim.
If ya did, you'd see where your statement is wrong..

The fired case is .469" at the very bottom unsized with any die...and the same fired case is .471" at the bulge.
When ran through the Wilson die it measures .470" over the bulge but .469 on the case body near the very edge the die does not size...cause it's a smaller dia...
You can see where the die stops ..
If you care to look.
That's why you should use a blade micrometer.
Or mike the very edge of the case head if rim is smaller than the case body...
Again the die sizes the bulge not all the way down to the case rim.
Belted mags do not size the belt...the problem area is the bulge before the belt.
Same area is the problem in beltless cases, the bulge...how much the brass springs back and how much the die sizes it down with respect to the chambers dia at that point.
Same with the Glock pistol cases as mentioned and roll forming the cases.
"None so blind, as those who will not see."
 

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#31
918v said:
You’re incorrect
Click to expand...
And you...are wrong and you know it.
But will not admit it.
Went to the bulge area which is correct, and stayed away from mentioning sizes all the way to the rim... the last time.
So maybe you actually see the error of your measurement but now will not admit you were wrong.
If you compentent enough to measured the area with a blade micrometer you'd find the same thing I did with the caliper.
The blade Mike doesn't lie, it is what it is.
You are definate total waste time...
But you most likely learned I am correct...if you looked at any of the evidence intelligently.
If the solid head expanded to .471" your primers would fall out of the case.
 
#34
918v said:
Look at the pics and read the damn micrometer
Click to expand...
So here ya go Slick...PROOF!
The Hornady die is screwed all the way down to the shell holder with cam over pressure...
A 308 case is sized at ram full up position and contacts the shell holder.
Ram is relaxed ...shell holder removed.

LOOK AT THE DIE WITH THE CASE STILL IN IT AT THE FULL SIZE POSITION. THE SHELL AND RAM IN FULL CONTACT ....
IT CLEARLY DOES NOT SIZE ALL THE WAY TO THE RIM!

BUT HAS A GAP OF UNSIZED CASE LEFT
FACT AS ALL CAN CLEARLY SEE!

BUT WAIT THERE IS MORE!...THE DIE HAS A RADIUS OR CHAMPHER ON THE DIE TO FURTHER ADD TO THE UNSIZED PORTION OF THE CASE HEAD.

ALL FACT AS ANY LOW IQ PERSON CAN SEE.

So if you would have followed my instructions on how to mike it... you wouldn't look like such an insistant idiot and fool with egg all over your face.

Presenting as an emotionally immature dude without a clue...only a Democrat believes his lies, and never changes his faulty presentation.
A 1st grader could easily see, when presented with the full picture.

Today's lesson.
Instead on insisting on being right investigate what is being told ...some have a lot more experience in case forming and making cases from other calibers... you might learn something from them.

Can you make a 6mm ARC from a 308?
Or a 6 Dasher or 35 Rem from a 308?
What about 30 Remington, 405 WSL, 351 WSL, 30 RAR, 338 RCM, 510 whisper, or a host of other obsolete calibers from available brass cases.
Can you make brass by the hundreds or even a thousand if needed?
Look no head stampds, 250 formed cases from basic brass.
Make your own case forming dies, or bullet sizing dies? Bullets? Chamber your own rifles?
It's obvious you know little about dies, and can not take instruction... you're fired.
Need another candidate for this apprenticeship.
 

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#38
918v said:
Lol!!! Just because your dies don’t work doesn’t mean everyone is in the same boat.
Click to expand...
So here is the other part of by design.
The FL die doesn't size down to the rim ...because it doesn't have to.
This is a 308 chamber with the sized case, notice the amount of brass case head out of the chamber unsupported...this is the solid head and doesn't get resized here.

If it would expand the same as the bulge on many occasions the primer would fall out as it does with hot loads or over pressure loads where the primer pocket only lasts 2 or 3 firings.
This is the area one measures with a blade micrometer to get accurate case head expansion it you were to compare factory loads to a reload to get similar pressures.

This is for normal people, not delusional dearranged Democrats who believe in 73 genders like 918 v above, which at this point is the best compliment he has earned.
 

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#40
918v said:
Stop it you’re hurting my feelings
Click to expand...
It's your delusional wilful stupidity that's the problem,... and I could care less about your feelimgs. Your feelings are your problem.
Don't like reality,...change, or die in your delusional fantasy mental box of wilful stupidity.
Unfortunately the outlook doesn't look good for you... yet I remain hopeful, unfortunately fearing I have wasted my time on you, but may have helped out others in the process.
 
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