flintbuilder
Inactive
awesome idea, i will try the feeler gauges before i start grinding shell holders or anything. and rotating the brass a few times.
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tight chamber?
- Thread starter flintbuilder
- Start date
JeepHammer
Moderator
At the risk of getting another post closed by adminstration...
This is probably an either/or deal,
Either the case from Datum line (on the case shoulder isn't being beat back enough ('Camming Over' the press shouldn't be required), to the case head *Should* fit the chamber.
If the case is too long, it simply won't fit and the bolt/chamber are sizing your brass, which is hard on the bolt/receiver.
Or,
The brass has bloated, swollen up when it was fired.
If the brass you are shooting the brass that come out of the same chamber, it shouldn't have bloated excessively.
The bloat is usually about 1/4 or 1/3 the way up the brass from the headstamp.
The craze of 'Small Base' dies was invented to try and combat the bloat issue...
Now, a Datum Line adapter will allow you to figure out if you have a shoulder issue or not.
I'm not sure I'd use a randomly drilled and champfered spacer from home Express or not, but a properly drilled adapter will give you a pretty good idea what's going on.
Keep in mind, some of the super tight chambers aren't actually SAAMI specification.
If you read the small print closely, you will find it says 'Semi-Finished Chamber' and advises you to see a qualified gunsmith for proper finish...
A legal disclaimer to keep the lawyers off their back when giving you a tight chamber that won't take every piece of crap ammo out there, but some are a little too tight...
Again, the dies ARE NOT SACRED, you CAN shave a little off the bottom to push the shoulder back further, WITHOUT stretching the press frame to near failure point (or past failure point).
When you 'Cam Over', you are stretching everything, bending the ram, etc. And all that spring action isn't going to give you repeatable results, so your brass comes out all over the place.
First, make brass that fits your chamber, then make brass that is consistent.
To tell consistent you will need ACCURATE MEASURING TOOLS and adapters.
You will pick this up as you go, the first order of business is making brass fit the chamber,
And if that means modifying dies to bend that brass into shape, so be it.
This is probably an either/or deal,
Either the case from Datum line (on the case shoulder isn't being beat back enough ('Camming Over' the press shouldn't be required), to the case head *Should* fit the chamber.
If the case is too long, it simply won't fit and the bolt/chamber are sizing your brass, which is hard on the bolt/receiver.
Or,
The brass has bloated, swollen up when it was fired.
If the brass you are shooting the brass that come out of the same chamber, it shouldn't have bloated excessively.
The bloat is usually about 1/4 or 1/3 the way up the brass from the headstamp.
The craze of 'Small Base' dies was invented to try and combat the bloat issue...
Now, a Datum Line adapter will allow you to figure out if you have a shoulder issue or not.
I'm not sure I'd use a randomly drilled and champfered spacer from home Express or not, but a properly drilled adapter will give you a pretty good idea what's going on.
Keep in mind, some of the super tight chambers aren't actually SAAMI specification.
If you read the small print closely, you will find it says 'Semi-Finished Chamber' and advises you to see a qualified gunsmith for proper finish...
A legal disclaimer to keep the lawyers off their back when giving you a tight chamber that won't take every piece of crap ammo out there, but some are a little too tight...
Again, the dies ARE NOT SACRED, you CAN shave a little off the bottom to push the shoulder back further, WITHOUT stretching the press frame to near failure point (or past failure point).
When you 'Cam Over', you are stretching everything, bending the ram, etc. And all that spring action isn't going to give you repeatable results, so your brass comes out all over the place.
First, make brass that fits your chamber, then make brass that is consistent.
To tell consistent you will need ACCURATE MEASURING TOOLS and adapters.
You will pick this up as you go, the first order of business is making brass fit the chamber,
And if that means modifying dies to bend that brass into shape, so be it.
RC20
He's trying to size the brass an test it in his rifles chamber by feel to get a zero headspace reading.
Got it. I know you can sort of do that.
Something seriously wrong if you have to do a hard cam over, and really anything more than a kiss.
I was thinking a tight chamber but then the brass would not go in either.
JeepHammer said:At the risk of getting another post closed by adminstration...
You didn't get the last one closed. I was reconsidering Jmorris's comment about how far it was drifting from the OP and you posted while I was in the act of composing the closing post. So we simply overlapped, and I was surprised your post was there when mine went up. Another thread more directly on the off-OP topics is fine.
Don Fischer
New member
I don't get why all this grinding is going on. What brand of die is it? Whatever it is it should return the whole case to SAMMI spec's. If it doesn't, I send it back. He said he'd fired the case's three time's but didn't say the case wouldn't chamber in his rifle. Neck size till the bolt won't close on a case in the chamber. From there start setting the die down till the bolt will close on the MTY case. If I though for one moment that I had to grind on the shell holder or die to get it to work right, it would get sent back to the maker. I don't think any die maker is in the business of making die's that need custom formed at home to work!
flintbuilder
Did you try store bought loaded rounds . What rifle is it ? Did you measure your fired cases at the neck , just below the shoulder , center , head & just above . Once you get the comparator you'll be able to check length . I never had your problem in F/L sizing . Why your die can't size your case down enough stumps me , in most cases the die oversized the case when your ram is at the top & you screw the die down to the shellholder until all thread slack is removed without can over. Do you have any new unfired brass to check in your chamber .
Did you try store bought loaded rounds . What rifle is it ? Did you measure your fired cases at the neck , just below the shoulder , center , head & just above . Once you get the comparator you'll be able to check length . I never had your problem in F/L sizing . Why your die can't size your case down enough stumps me , in most cases the die oversized the case when your ram is at the top & you screw the die down to the shellholder until all thread slack is removed without can over. Do you have any new unfired brass to check in your chamber .
I had an email exchange with RCBS recently, in which they said:
So, any die you buy could be as much as 0.004" different from the one in the next box, from 0.001" to 0.005" under SAAMI minimum. Springback, IME is always at least around about 0.001", so the largest die would bring the least springy case just to SAAMI chamber minimum, but the .223 case minimum is -0.004" shorter than that, and most commercial ammo makers seem to put their cases near case minimum. This would explain why the OP could find his resized ammo bigger than new ammo. He got a die on the larger size of the tolerance range, even though everything is still within SAAMI spec.
For most handloaders, if they segregate their brass by the gun they shoot it in, it won't matter that the die does not make brass match the manufacturer's number because they are going to fire the resized case in the same chamber, and it should be no bigger than it was coming out of that gun, and so it should function fine. What is happening to the OP is he appears to have cases growing in headspace during resizing for some reason.
One other possibility, and one I don't like to bring up as it points to a gun problem, is chamber axis alignment. Does a once fired case fits back into the chamber with the headstamp in any orientation around the clock in the chamber or does it fit in smoothly only with one orientation? If the latter is the case, the chamber could be reamed off-axis with the bore. That results in case rubbing, as resizing doesn't fully square the head back up.
Otherwise, it's just a matter of the die being on the big side and the chamber being on the short side and the combination resulting in a snug fit. If just a 0.001-0.002" shim under the case does the trick, then it's likely just a tolerance stacking problem and grinding the shim thickness from the die mouth is workable.
RCBS Tech said:…We base our rifle reloading dies on {a target value of} -.003 off minimum SAAMI spec, with +/- .002 machining.
So, any die you buy could be as much as 0.004" different from the one in the next box, from 0.001" to 0.005" under SAAMI minimum. Springback, IME is always at least around about 0.001", so the largest die would bring the least springy case just to SAAMI chamber minimum, but the .223 case minimum is -0.004" shorter than that, and most commercial ammo makers seem to put their cases near case minimum. This would explain why the OP could find his resized ammo bigger than new ammo. He got a die on the larger size of the tolerance range, even though everything is still within SAAMI spec.
For most handloaders, if they segregate their brass by the gun they shoot it in, it won't matter that the die does not make brass match the manufacturer's number because they are going to fire the resized case in the same chamber, and it should be no bigger than it was coming out of that gun, and so it should function fine. What is happening to the OP is he appears to have cases growing in headspace during resizing for some reason.
One other possibility, and one I don't like to bring up as it points to a gun problem, is chamber axis alignment. Does a once fired case fits back into the chamber with the headstamp in any orientation around the clock in the chamber or does it fit in smoothly only with one orientation? If the latter is the case, the chamber could be reamed off-axis with the bore. That results in case rubbing, as resizing doesn't fully square the head back up.
Otherwise, it's just a matter of the die being on the big side and the chamber being on the short side and the combination resulting in a snug fit. If just a 0.001-0.002" shim under the case does the trick, then it's likely just a tolerance stacking problem and grinding the shim thickness from the die mouth is workable.
condor bravo
New member
Grinding wheels were made for grinding a small amount from the mouth of the die. You might be able to get a small one at the hardware store that can attach to an electric drill. That makes the job quick and easy. I have done that to at least six sizing dies.
So, any die you buy could be as much as 0.004" different from the one in the next box, from 0.001" to 0.005" under SAAMI minimum. Springback, IME is always at least around about 0.001", so the largest die would bring the least springy case just to SAAMI chamber minimum, but the .223 case minimum is -0.004" shorter than that, and most commercial ammo makers seem to put their cases near case minimum. This would explain why the OP could find his resized ammo bigger than new ammo. He got a die on the larger size of the tolerance range, even though everything is still within SAAMI spec.
Again, I make datums, I purchase datums and collect datums; I am the fan of the standard and I am the fan of transfers, when I want to know the difference between one die or another I measure. In the beginning I had no clue how many reloaders had limited skills in a machine shop; I do not know how it happened but I have 3 machines that grind gages to length, they also grind gages with angles/tapers and then there is the diameter. So the machines also makes pilots. I can not imagine telling someone all a reloaders has to do is grind a little off the end of the die.
F. Guffey
F. G.
The average reloader can't do the things you do . You just want the tool you buy to work an do the job. In this case something is screwy , not the norm . As Unclenick stated , chamber issue or die . Or we may not be getting accurate information from poster . Some shooters hardly ever clean their rifle , when helping someone we have to rule out every scenario , I would think , answering back from the poster is needed. Sometimes I read posts where someone posts a problem an never answers back . Not this case . Most of the time someone finds the problem . Always makes good reading .
Chris
The average reloader can't do the things you do . You just want the tool you buy to work an do the job. In this case something is screwy , not the norm . As Unclenick stated , chamber issue or die . Or we may not be getting accurate information from poster . Some shooters hardly ever clean their rifle , when helping someone we have to rule out every scenario , I would think , answering back from the poster is needed. Sometimes I read posts where someone posts a problem an never answers back . Not this case . Most of the time someone finds the problem . Always makes good reading .
Chris
Last edited:
My Kimber 223 bolt gun has a really tight chamber. I have both Redding and CH4D die sets and added an RCBS small base FL sizer die. Of the three FL sizing dies the CH4D and RCBS size the brass small enough to bump the shoulder back to fit the chamber. The Redding die does not modify the body of the fired brass, just the neck. I discovered that with some shims in the shell holder and careful measurement of the cases. I like the PTG comparator tool that looks like a large hex nut. The Redding die works great for my 223 Mini 14.
flintbuilder
Inactive
Hey guys.
So I removed the ejector and the extractor. ahhhh. now I can feel the brass on the bolt with out interference. So with small cam over i am getting very small amounts of friction when closing the bolt. So I made a shim out of a pop can and it did just the trick. After a quick sizing with the shim it is a perfect fit. So rather the continuing to use a smashable shim I ground down the shell holder 2 thou and it works beautifully. All thanks to you guys and your help. Just a slightly small chamber. I have never tried any thing other than my own reloads in the chamber. No factory ammo, but I will. I feel great relief to know what was going on and to have the problem solved.
Thanks a ton to all.
So I removed the ejector and the extractor. ahhhh. now I can feel the brass on the bolt with out interference. So with small cam over i am getting very small amounts of friction when closing the bolt. So I made a shim out of a pop can and it did just the trick. After a quick sizing with the shim it is a perfect fit. So rather the continuing to use a smashable shim I ground down the shell holder 2 thou and it works beautifully. All thanks to you guys and your help. Just a slightly small chamber. I have never tried any thing other than my own reloads in the chamber. No factory ammo, but I will. I feel great relief to know what was going on and to have the problem solved.
Thanks a ton to all.
Tight chambers: I cut short chambers, I start by determining the length of the chamber in the new barrel. I have 20 receivers that require a case head protrusion of .110" + .005" for clearance. Before I remove a barrel I determine the length of the chamber from the shoulder/datum to the bolt face.
Papa bare, momma bear and baby bare chambers? I have no problem measuring the length of the chambers in thousandths with one gage, and then there are methods and techniques that do not use head space gages, again, this stuff does not lock me up.
F. Guffey
Papa bare, momma bear and baby bare chambers? I have no problem measuring the length of the chambers in thousandths with one gage, and then there are methods and techniques that do not use head space gages, again, this stuff does not lock me up.
F. Guffey
JeepHammer
Moderator
WOW!
You guys go at this different than a tool & die maker would!
First off, consistency!
The big IDEA is to be as CONSISTANT as possible, no matter what the case turns out like (as long as it fits the chamber).
Same press, same dies & shell holder.
The LEAST reliable part of the process is muscle force...
Try holding 20 pounds on an accurate scale and see how much that scale moves around.
(Probably the reason so many die makers recommend using the die/shell holder contact as a mechanical stop)
What *I* do, personal choice, so I don't need a bunch of crap about it...
Find (or make) a die that bends the case WALLS back in where they belong, and no more.
No sense in undersizing the case when it's not needed.
Then I shave the bottom of the die (usually lapped, very rarely need a lathe cut) to get the shoulder where it belongs.
The dies get a DEDICATED shell holder. Shell holders are cheap, if you can't afford one, then you shouldn't be spending money on guns or ammo...
The shell holder can also be shaved (lapped or ground).
Once the brass is 99% there, the old feeler gauge under the brass usually gets it to 100%.
This goes right along with what I've been saying all along, the dies are NOT sacred!
Make them fit the application...
When the dies are seriously undersizing the necks, you simply lap out the neck of the die until it fits YOUR brass & the bullet you are using.
When you want a little more neck tension, you simply lap the expansion ball down.
99% of the time this will elminates the need for crimping the neck in all but the most contrary feeding rifles...
Again, no sense in overworking the crap out of the brass when you don't need to.
When RCBS says they make there dies 0.003" undersized, that doesn't mean your chamber isn't under or over size, so you can have a serious gap between brass & chamber.
Again, seriously undersized brass blows out, gets seriously undersized again... And again... Overworking the brass when it doesn't need to be with a little work to the dies.
The 'Perfect' dies cut with the same tool used to cut the rifle chamber.
Barring that, getting a case sidewall fit FIRST is the hardest part, since it's hardest to adjust the sidewalls of the die.
Adjusting the depth/Datum Line is pretty easy,
Opening up the neck is harder than reducing the expander ball size, but neither is too difficult and the base 'Tools' cost about $25 for all the dies you own...
(Hand drill motor, wooden dowel rods, piece of old leather belt, lapping compound, sand paper)
For those that have or intend to buy 'Match Chamber' rifles, keep in mind the current crop of super tight chambers have right in the paperwork for the rifle the chambers are 'Semi-Finished' and recommend you see a qualified gunsmith if ammo doesn't fit the chamber.
Most will swallow tight SAAMI specification ammo (read American factory ammo), but reloaders quickly realize their reloading practices/equipment isn't up to the tolerance standards...
Sometimes the world doesn't fit, simply makes adjustments!
You guys go at this different than a tool & die maker would!
First off, consistency!
The big IDEA is to be as CONSISTANT as possible, no matter what the case turns out like (as long as it fits the chamber).
Same press, same dies & shell holder.
The LEAST reliable part of the process is muscle force...
Try holding 20 pounds on an accurate scale and see how much that scale moves around.
(Probably the reason so many die makers recommend using the die/shell holder contact as a mechanical stop)
What *I* do, personal choice, so I don't need a bunch of crap about it...
Find (or make) a die that bends the case WALLS back in where they belong, and no more.
No sense in undersizing the case when it's not needed.
Then I shave the bottom of the die (usually lapped, very rarely need a lathe cut) to get the shoulder where it belongs.
The dies get a DEDICATED shell holder. Shell holders are cheap, if you can't afford one, then you shouldn't be spending money on guns or ammo...
The shell holder can also be shaved (lapped or ground).
Once the brass is 99% there, the old feeler gauge under the brass usually gets it to 100%.
This goes right along with what I've been saying all along, the dies are NOT sacred!
Make them fit the application...
When the dies are seriously undersizing the necks, you simply lap out the neck of the die until it fits YOUR brass & the bullet you are using.
When you want a little more neck tension, you simply lap the expansion ball down.
99% of the time this will elminates the need for crimping the neck in all but the most contrary feeding rifles...
Again, no sense in overworking the crap out of the brass when you don't need to.
When RCBS says they make there dies 0.003" undersized, that doesn't mean your chamber isn't under or over size, so you can have a serious gap between brass & chamber.
Again, seriously undersized brass blows out, gets seriously undersized again... And again... Overworking the brass when it doesn't need to be with a little work to the dies.
The 'Perfect' dies cut with the same tool used to cut the rifle chamber.
Barring that, getting a case sidewall fit FIRST is the hardest part, since it's hardest to adjust the sidewalls of the die.
Adjusting the depth/Datum Line is pretty easy,
Opening up the neck is harder than reducing the expander ball size, but neither is too difficult and the base 'Tools' cost about $25 for all the dies you own...
(Hand drill motor, wooden dowel rods, piece of old leather belt, lapping compound, sand paper)
For those that have or intend to buy 'Match Chamber' rifles, keep in mind the current crop of super tight chambers have right in the paperwork for the rifle the chambers are 'Semi-Finished' and recommend you see a qualified gunsmith if ammo doesn't fit the chamber.
Most will swallow tight SAAMI specification ammo (read American factory ammo), but reloaders quickly realize their reloading practices/equipment isn't up to the tolerance standards...
Sometimes the world doesn't fit, simply makes adjustments!