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8185854610
01-17-2017, 11:17 PM
I have noticed that Rcbs 223 small base dies are stretching my lc 2013 cases..
New case fired .001 to .002 length increase when fired in ar-15. I measure the case and size it with a small base die set correctly for .002 shoulder bump.
The case stretches .005 when sized. Now the case is 1.756, original length 1.750 +.001 from being fired and + .005 from sizing.. Fired only one more time and I am at 1.762. Trim is know necessary. So two firing with small base die and must be trimmed.

A guy at the range uses same exact gun and load lc 2013 case, Hornady fmjbt 55 grain 26.0 grains blc-2 and light crimp. He uses std fl dies works fine in his gun. He could not recall how many times fired before trimming.

My question is if you have no malfunctions using std fl dies about how many times fired before you hav to trim your cases.

J-cat
01-18-2017, 3:11 AM
The sb die is not causing your cases to stretch. Firing in your AR is causing them to stretch. The reason your buddy is not trimming his brass is because a 556 chamber is .050" longer than min trim length. That means 10 reloads before the case is too long.

8185854610
01-18-2017, 5:03 AM
Both guns ar 556 as is the ammo lc2013 cases are 556. As my post reads firing a new case that is 1.750 long stretch to 1.751 to1.752 after sizin in small base die they stretch another .005. But thanks

bazineta
01-18-2017, 6:35 AM
I guess the first question is, is your chamber undersized such that you need to use a small base die?

Reason I ask is that I run LC brass that's been fired in M240Bs through standard Redding dies, and the results are in spec; while I have small base dies, I've never needed to actually use one.

J-cat
01-18-2017, 7:14 AM
Both guns ar 556 as is the ammo lc2013 cases are 556. As my post reads firing a new case that is 1.750 long stretch to 1.751 to1.752 after sizin in small base die they stretch another .005. But thanks

You can't compare his fired brass to your resized brass. Resized brass will always be longer.

fguffey
01-18-2017, 7:23 AM
=8185854610;19518089]I have noticed that Rcbs 223 small base dies are stretching my lc 2013 cases..
New case fired .001 to .002 length increase when fired in ar-15. I measure the case and size it with a small base die set correctly for .002 shoulder bump.
The case stretches .005 when sized. Now the case is 1.756, original length 1.750 +.001 from being fired and + .005 from sizing.. Fired only one more time and I am at 1.762. Trim is know necessary. So two firing with small base die and must be trimmed.

There is a lot that happens between pulling the trigger and the bullet leaving the barrel reloaders do not understand. I have not given up on believing the reloader understands the case does not have head space and the case has two length; one from the end of the neck to the case head and the other from the datum to the case head. And then there is the perception they are able to move the shoulder; reloaders always start with :I BUMP...", and I always ask: "HOW?". NO one answers me, they just get mad or angry and snarky.

If reloaders would think about 'IT' they would understand the die does not stretch the case, the only direction brass moves is toward the neck. Not my fault but reloaders believe they can move the shoulder. Moving the shoulder is a bad habit. I find moving the shoulder is most difficult, it is easier for a reloader to claim they move the shoulder than it is to move the shoulder.

There are reloaders on the Internet that claim they have case heads that are not against the bolt face when the trigger is pulled, when an internet reloader tells me their case heads are not against the bolt face I tell them there is nothing they can do to prevent case head separation if the case head is not supported; and, they have no clue what all of that is about.

Back to the distance from the shoulder/datum to the case head, every reloader insist they move the shoulder and I ask; HOW? How can a reloader move the shoulder of a case? I can not move the shoulder of a case with a die that has case body support. I know, "Yes I can" is not an answer. I can not move the shoulder of a case with a die that has case body support; Why?

I can move the shoulder of a case with a die that does not have case body support; What is it a reloaders does not understand about moving the shoulder when firing and sizing?

F. Guffey

8185854610
01-18-2017, 7:28 AM
I am not comparing his brass to mine. he reloads also using regular fl dies and i am using small base. After firing I am taking meadurements of my own.

I am trying to find out what other people find the number of firings are before trim using std fl dies.

Also the brass I am using started out as new not once fired lake city. Thanks

mike.h
01-18-2017, 7:41 AM
I tried the small base dies for my .223 wylde chambered AR, but felt they overworked the brass. I now use the redding FL resizing die.

J-cat
01-18-2017, 7:43 AM
The only difference between a regular and small base die is the sb die is .001-.002" tighter at the base. That little bit does not induce .005" of case stretch.

Second, unless you are measuring both his and yours before assembly and after resizing your comparison is invalid. New brass varies in length more than that.

the86d
01-18-2017, 8:04 AM
Do RCBS X-DIEs really work for not trimming as often, or at all?

someoneeasy
01-18-2017, 8:40 AM
To avoid this problem, I use this secret technique that most reloaders try to avoid. Ready for it? I trim my brass after every firing! :eek:

No measuring and sorting or wasting time to keep track of how many times a case has been fired, just clean, trim, load, shoot.

It seems like you waste more time trying to measure and avoid trimming than just running it through the trimmer. I dont need to add another step in my process to slow me down, I just run it through the trimmer. If it only trims a little bit, then it trims a little bit, if it trims more, then it trims more.

8185854610
01-18-2017, 9:00 AM
Any idea how many times fired with fl dies befire necessary to trim, thanks for your input

8185854610
01-18-2017, 9:04 AM
Thanks i re-read you post

J-cat
01-18-2017, 9:57 AM
Any idea how many times fired with fl dies befire necessary to trim, thanks for your input

My chamber is 1.795" long. So from 1.750" it will take 8 reloads.

racinjason233
01-18-2017, 10:31 AM
[QUOTE=someoneeasy;19519181]To avoid this problem, I use this secret technique that most reloaders try to avoid. Ready for it? I trim my brass after every firing! :eek:

+1

Paseclipse
01-18-2017, 10:48 AM
I have noticed that Rcbs 223 small base dies are stretching my lc 2013 cases..
New case fired .001 to .002 length increase when fired in ar-15. I measure the case and size it with a small base die set correctly for .002 shoulder bump.
The case stretches .005 when sized. Now the case is 1.756, original length 1.750 +.001 from being fired and + .005 from sizing.. Fired only one more time and I am at 1.762. Trim is know necessary. So two firing with small base die and must be trimmed.

A guy at the range uses same exact gun and load lc 2013 case, Hornady fmjbt 55 grain 26.0 grains blc-2 and light crimp. He uses std fl dies works fine in his gun. He could not recall how many times fired before trimming.

My question is if you have no malfunctions using std fl dies about how many times fired before you hav to trim your cases.



When I first started loading 223 I was also on the SBD bandwagon until I figured out it really isn’t needed unless your chamber is on the tight side. SBD’s work brass a lot harder than FL die’s because it’s sizing the brass to the minimum.

Maybe give FL sizing a try and only use SBD’s if you really need to? You’ll probably get more life out of your cases.

Perhaps the .005” case stretch during resizing has something to do with the expander ball pulling through the case neck?


To avoid this problem, I use this secret technique that most reloaders try to avoid. Ready for it? I trim my brass after every firing! :eek:

No measuring and sorting or wasting time to keep track of how many times a case has been fired, just clean, trim, load, shoot.

It seems like you waste more time trying to measure and avoid trimming than just running it through the trimmer. I dont need to add another step in my process to slow me down, I just run it through the trimmer. If it only trims a little bit, then it trims a little bit, if it trims more, then it trims more.


^^^^ This.

I do the same thing because it’s faster to run cases through the trimmer than to individually measure each one or even check them in a gauge.

J-cat
01-18-2017, 10:59 AM
One benefit of not trimming is a longer neck which helps to stop bullet setback during feeding by virtue of more surface area adhering to the bullet.

bazineta
01-18-2017, 11:55 AM
OP, I just trim every time -- I have a Wilson trimmer, and frankly once practiced with it, it's practically as fast to trim as it is to measure, so I just trim.

However, the thing is, unless you have a very tight match chamber, I'd recommend trying a standard die instead of a SB die; no point in working brass without necessity.

ar15robert
01-18-2017, 7:38 PM
I shoot .223 out of my mini 14 and ar15 plus i pick up everyone elses in my group who dont reload so i have multiple brass from different guns.

I also use the FL dies and have been doing so for about 16-17 years with no issues.I started with small base dies but found they werent needed for my rifles.I also trim all of my brass after each firing or the brass i get it just makes things easier down the line esp if you do light crimping.Some brass i see more material coming off when trimming others not so much.

1911colt.ml
01-23-2017, 2:34 AM
I use the Small base die because I fire my 223 reloads out of several different rifles. Most of my AR type chambers are on the tight side so I like them.

LynnJr
01-23-2017, 5:29 AM
When you first get your new brass it has to fit in every chamber including those made for bolt guns.
The chambers in semiautomatic guns tend to be larger so the cases can feed and extract without any jamming issues.
What that means is the brass from a semiautomatic tends to come out larger.
By using a small base die you are now squeezing the base down more than normal and that brass has to go somewhere so it grows in length.
Yes you can just keep trimming it but you are weakening the area right in front of the web by oversizing your brass.
Small base dies are not where you should start they are used when properly set up full length dies are not sizing the base of the case enough for proper functioning.
If standard dies work with your guns chamber you are over working your brass with small base dies and it won't last as long.

J-cat
01-23-2017, 6:50 AM
Not true. The extra .001" of sizing at the base does not reduce the life of the case in any meaningful way. I have reloaded FGMM 20 times, yes 20 times, using a small base die. I trimmed .070" of case neck in the process as the case stretched. What goes first is the primer pocket, then the case head, and SB sizing doesn't play into it.

'ol shooter
01-23-2017, 12:13 PM
:lurk5: A good discussion.

LynnJr
01-23-2017, 12:30 PM
Not true. The extra .001" of sizing at the base does not reduce the life of the case in any meaningful way. I have reloaded FGMM 20 times, yes 20 times, using a small base die. I trimmed .070" of case neck in the process as the case stretched. What goes first is the primer pocket, then the case head, and SB sizing doesn't play into it.

100% wrong.
If your trimming brass after each firing that brass is coming from somewhere.
The OP's brass is growing in length because the chamber is allowing the brass to expand outward and forward and he is then squeezing it down excessively.
This causes casehead separations and loss of brass life.
In your example your gun may need small base dies but if it doesn't you are also overworking your brass.
Yes you may be getting g 20 loads from a piece of brass but without small base dies you might get 59 reloads. We don't know because you only gave us part of the story.

8185854610
01-23-2017, 12:52 PM
UPDATE I took 20 pieces of brass and measured them for overal length. They are lake city 556 2013 brass. Bought new have been fired twice. I set up redding small base dies with .002 shoulder set back. Process 10 pieces of brass which were exactly 1.755 in length. Lubed with imperial wax. And full sized them, the remeasured the average length increase was .006.
I repeated the same process with identical brass with lee std full length dies same shoulder set back. The average increase in length for the 10 cases was .005. The lee dies offer much less force.

fguffey
01-25-2017, 7:45 AM
UPDATE I took 20 pieces of brass and measured them for overal length. They are lake city 556 2013 brass. Bought new have been fired twice. I set up redding small base dies with .002 shoulder set back. Process 10 pieces of brass which were exactly 1.755 in length. Lubed with imperial wax. And full sized them, the remeasured the average length increase was .006.
I repeated the same process with identical brass with lee std full length dies same shoulder set back. The average increase in length for the 10 cases was .005. The lee dies offer much less force

Less force? And that is it? I would think someone could find another 'therefore'. If I was interested in 'less force' I would use a force gage. And then there are gages that are not being used when making comparisons.

F. Guffey

8185854610
01-25-2017, 8:04 AM
It was about 1/2 the pressure (pressure on my arm guage) on the press lever with the standard dies, and that's it. Get a gauge and duplicate the test and post the update, might be helpful?

fguffey
01-25-2017, 8:13 AM
The sb die is not causing your cases to stretch. .

Because reloaders are conditioned to respond to words, groups of words and phrases it is impossible to separate stretch and flow. There was a time I would ask the question: "Is it stretch or flow or is it stretch and flow?" and that just made every reloader angry and it seemed they scorned the day they ever learned to read.

It makes no sense to me how a die can stretch a case. It is right up there with moving the shoulder: I ask "How do you do that?", no one has ever said; "I do not know".

F. Guffey

fguffey
01-25-2017, 8:19 AM
It was about 1/2 the pressure (pressure on my arm guage) on the press lever with the standard dies, and that's it. Get a gauge and duplicate the test and post the update, might be helpful?

John Lewis, I understood every thing you said but I thought with all of the talent reloaders on this forum someone could add something to your conclusion. Something like: "This is what he discovered' therefore, etc. etc..

F. Guffey