tight chamber?

F

flintbuilder

Inactive
Hey guys

long time reader, first time poster

Quick question.

Im using a factory hunting 223 bolt action rifle, with lapua brass that i have fired 3 times in only this rifle, with only neck sizing. I want to start to full size just enough to get 2 or 3 thou clearance after each firing to be more consistent with each reload

I have a RCBS 223 full length sizing die that when I use it, maximum sizing, the brass is still tight in my bolt action chamber. Do I understand correctly that when I remove the firing pin and place the brass in the chamber I should be able to close the bolt without friction, or with very small friction, to indicated the brass is sized to get a 2 or 3 thou head space?

What I do is raise the ram all the way up touch the die to the RCBS shell holder, advance the die a quarter turn to get cam over, size the brass, clean off the lube, try it in the chamber, and the de-pinned bolt wont close without a bit of force, like a knife through coolish butter. With a fired un-sized brass the bolt closes like a knife in cold butter. It is a better fit once i full length size it but still not a free floating bolt close.
Does this sound like I am doing something wrong, have a tight chamber, need a small base die?

The guy at the local shop said to use a small base die or to grind down the full length die because my chamber is just a tight chamber.

What should I do?:confused:

Thanks for any help
 
American made chambers are made to SAAMI spec. European chambers are made to CIP spec, that's different than SAAMI. Slightly smaller as I recall.
FL sizing dies take the cases to SAAMI spec too. The SB dies are usually for semi-autos and aren't required for bolt actions. An SB sizer sizes a few thou more than an FL die. It's an either/or but not both thing.
Anyway, all neck sized cases, regardless of the rifle or brand eventually require FL resizing. You might be there with your cases. It does sound like the easiest fix is an SB die though. Grinding an FL die won't do much of anything.
 
Before I went to a small base die, i’d grind a bit off the top of the shell holder and see if that helped. That will allow a teeny bit more shoulder setback.
 
Hey guys.
thanks for all the input. When I close the deprimed bolt it closes loose and floppy. I will remove the extractor/ejector and try it again. If that doesn't do it i will grind down the shell holder a thou at a time and see if that will get me to fit. the brass has not been annealed, i was planning on doing that, i will try that prior to sizing all of the brass if i can get one to fit with the above mentioned steps.
Great advice I will try them tommorow, stuck at work for a 13 hr shift today.
Thanks a ton!!!! Ill post tommorow to let you know how it went.
 
I have ground down at least a half dozen full length dies. Better than grinding some from the top of the shell holder that could weaken it
 
Taking a thousandth off the top of a shell holder isn’t going to cause it to fail. And the shell holder is the cheapest part involved. It has not caused any failure of the two I ground slightly.
 
A few tips for you to consider.

1. Open and close the bolt on an empty chamber to develope a sense how an unimpeded closing feels like.

2. With the extractor on, close the bolt on a brass. Open and pull back the bolt slightly, without ejecting the brass, and close again. The extractor may affect the first closing, but not the subsequent ones.

3. Test a factory round. Compare it to your sized brass.

4. When opening the bolt on your sized brass, do you feel resistance during primary extraction stage. Your chamber may be tight diameter-wise but not length-wise. Color the brass with ink may tell.

5. When sizing your brass, with the ram fully up, see whether there is gap between the die's bottom and the shell holder's top. If there is, don't bother to grind the die or the shell holder. They are not limiting yet.

6. Check brass overall length. Trim if it is over the maximum.

Hope it helps.

-TL

Sent from my SM-G930T using Tapatalk
 
How are you measuring your brass . What is the measurement from the base to the datum on the fired to the sized cases . when F/L sizing are you using the expander ball , its a good idea to add a little lube on the inside of the necks with a Q tip before sizing . I sounds like your cases are expanding with neck sizing and when your full sizing the case is getting longer . I full size only with the standard RCBS Full Size standard die using the Redding precision She'll holders set of 5. When you remove your firing pin assembly ,using only the bolt housing ,does it have a ejector plunger on the bolt face like on a Remington? Check also your trim length .
 
Thanks for the help guys.
I don't have a tool for measuring the datum line size, but am getting the hornady head space gauge set. I'm just measuring overall brass length with a caliper until i get the tool. I have length trimmed the sized cases to see if they were too long. still stiff. Ill keep trying the least invasive tips first and try them each until i get it.
keep the ideas coming.
Much appreciated.
 
I am trying to wrap my mind around the fact that you have to removed the bolt face parts to get this to work.

What make gun do you have to start with?
 
I have a RCBS 223 full length sizing die that when I use it, maximum sizing, the brass is still tight in my bolt action chamber. Do I understand correctly that when I remove the firing pin and place the brass in the chamber I should be able to close the bolt without friction, or with very small friction, to indicated the brass is sized to get a 2 or 3 thou head space?
Click to expand...

Reloaders do not consider the case can whip the press, when I size a case I determine if the case won or the press and die won. For me? it is so easy if I adjust the die down to the shell holder and then add 1/4 turn to the die I am lowering the die .017". When I check to see if the case won or the press won I measure the gap between the shell holder and bottom of the die.

And then? When I have a chamber that is longer than a go-gage length chamber I increase the gap between the shell holder and bottom of the die, in the perfect world and my press does not flex a die adjusted to the shell holder with an additional 1/4 turn should size the case to minimum length/full length.

F. Guffey
 
When you get the tool, remember it is a comparator and not an absolute measurement tool. You want to zero it on the new brass you have, then on fired brass and then on brass fired and resized and get an average of both.

You can improvise a comparator with a spacer. This is in .308 below. For .223 you want something with a hole about 19/64", so drilling out a 1/4" spacer probably makes the most sense.

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Welcome to TFL!

Im using a factory hunting 223 bolt action rifle, with lapua brass that i have fired 3 times in only this rifle, with only neck sizing. I want to start to full size just enough to get 2 or 3 thou clearance after each firing to be more consistent with each reload
Click to expand...

First question: what rifle??

Next question: why does it matter?
Meaning, other than your personal desire for consistency, is it something that will matter to the rifle you are using???

The forums are full of advice on how to measure.. well, everything, but measuring to get .xxx" off the lands or measuring to get a certain amount of "bump back" to the shoulder (and some other things), MAY NOT MATTER to your rifle's accuracy!

What is your rifle, and how is it shooting now??

seriously. All the tips, tricks, tools and gauges to make "the best" ammo are wasted effort (and money) if your rifle isn't up to the task of USING them to be more accurate.

Next question is "how accurate do you need to be?"

A .223 sporting rifle needs not be benchrest accurate, it needs to be sub-Minute of Varmint. (and this varies with the varmint! ;)

Remember, group size is total spread, in all directions, around the point of aim. A 1 MOA rifle will put all its rounds 1/2MOA from the point of aim.

It was mentioned to lube the inside of the case necks, so the expander button doesn't "drag" in the neck on the way out, possibly stretching the case. I use the RCBS liquid in the pump bottle, and it does a good job of getting in the necks, so I don't need to lube each case for that, individually.

TO get JUST the feel of the bolt closing on the case, you need to remove the firing pin assembly, and the extractor and ejector from the bolt body. (skip this if it has a Mauser style claw and ejector blade)

You COULD have a "tight" chamber, or you could just be looking at the build up of tolerances, tight chamber and "loose" sizer die, both within acceptable tolerance, but at opposite ends of the range.

Test with other makes of brass. Test compared to factory loaded ammo (which is always slightly undersize). Do this before spending any serious money on tools, gauges or mods to the rifle, or dies, or shell holder.

If you have a "minute of coyote" rifle, precision loaded ammo might make it a "minute of ground squirrel" rifle, but it might not. Don't expect miracles, but if you get them, give thanks.
 
RC20
He's trying to size the brass an test it in his rifles chamber by feel to get a zero headspace reading.
 
This may or may not help

I had a similar problem with my 1917 Eddystone. The culprit was a dirty chamber resulting in difficult chambering with FL-sized brass. Chamber looked clean but a healthy effort with a chamber brush it became a great deal cleaner. Result was chambering and ejection as designed. Occasionally a simple solution works.

The Eddystone is a good shooter.
 
Hi guys
RC20
My understanding is that you remove the bolt and apparently the extractor/ejector as well so that when the bolt is in the gun it will float freely and the tension of the removed parts don't interfere with the action being closed on a piece of brass. this way you can actually feel how tight the brass is in the chamber. if the other parts are still assembled you feel their function instead of the bolt closing on the brass. try it out.

44amp.
It matters because my rounds are getting tight in the chamber. tighter and tighter with each reloading from expansion. The RCBS full length die isn't bringing the brass back to a small enough size to fit without feeling tight. I know its not a bench rifle by a long stretch of the imagination. I just want to cycle the rounds with out having to fight the round into the chamber when a coyote runs in front of me.
The rifle is a run of the mill Thompson center venture predator.

Thanks guys. please keep helping me learn. i am still new at the reloading stuff
 
As some have pointed out, grind or file a little off the bottom of the die which will result in additional sizing and will not hurt the die at all.
 
One thing to realize is that neck-sized brass does get a little tighter with every firing and that every third to fifth round you may need to full-length resize again.

Before you go grinding dies and the like, try board memeber F. Guffey's favorite hack, and see if you can pick up a set of feeler gauges that are narrow enough to fit into the shell holder slot and support and lift the case head. If you know someone with shim stock, you can also use tin snips to make a piece that will fit. You have to remove the decapping pin to do this unless you have a shim washer or drill a hole for it through shim stock, because there's no way for the decapping pin to go through a solid feeler gauge. But you usually can fit gauges up to around 0.005" under most brass in its shell holder and that will add that much resizing to the overall case length. This step will tell you how much additional resizing you need, as will the comparator measuring method.

One other thing to try is just running the same brass up into the case again, counting to five, and withdrawing it, rotating it about 1/3 turn and repeating, then withdrawing and rotating another third of a turn and doing it again. IME, this usually shaves another 0.002" off the head-to-shoulder length of the case.
 
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