Your opinion on crush fit brass

[LTH]

I wanted to see where the shoulders were on once fired brass at my rifle's shoulder in the chamber.
This is with a vanguard s2 3006.
The 2.0395" far right is the same position as a new unfired case.
The 1st and 2nd chamber pretty good.

Any opinions appreciated from your experiences to bump or crush !

 

[Walkalong]

There is nothing to be gained by a crush fit in my opinion. Tight yes, crush no.

 

[gamestalker]

I get what it is your trying to accomplish. Actually, I think I brought this topic up a while back, and someone here posted a link for the tool. I think Hornady makes it. I wish I could remember what it's called. Maybe the person who posted the link will do so again.

Don't you just hate having to waste components to get the shoulders pushed out? I certainly do, and IMO, I really think the manufacturer's should get more involved with this aspect of brass preparation. The idea I had, was if I could get the shoulders pushed out enough, I can always just use the FL die to bump them back to zero. I've tossed around a couple of ideas on how to accomplish this using hydraulics. The crush fit idea doesn't seem like it would be very practical IMHO, seems like the results would be rather inconsistent.

GS

 

[LTH]

Hi Gamestalker, I have hornadys tool for shoulder measurement and the bullet oal length gauge.
By smoking the shoulders , I wanted to get an idea of what the distance of bolt to chamber shoulder is for my rifle.
It looks like it's somewhere at the 2.041" .

I wanted to see how close the gauge is as well.

By doing this , I'm trying to understand about case stretch , max head space , excessive head space and what folks are saying about slight crush fit etc......

And also comparing to SAAMI.

Fooling around with my FL die , I took one case back to a unfired position a was able to stretch one.

I thought that if anyone had a vanguard , I could see what they are doing or compare notes .

Thanks

 

[ironworkerwill]

There is nothing to be gained by a crush fit in my opinion. Tight yes, crush no.

I like this statement.

I guess at times we can loose concentration resizing a batch and short stroke one. We know right off what went wrong. Make sure you run them trough the case gauge for SD and hunting applications. One grain of grit and your out of business on the follow up shot.

 

[LTH]

One grain of grit and your out of business on the follow up shot.

You know what ! That is an excellent point , thank you !
I guess that's why it's said to bump 1 to 2 thou. back when resizing and never why they advise it.

 

[gamestalker]

I use a home made method to measure datum line on the shoulder to case head. Very simplistic, yet it delivers repeatable results. I haven't been able to find a commercial gauge that satisfies my quest for repeatable measurements, and those that claim to be accurate are expensive, only to find out they aren't.

Something I have done numerous times, and still do depending on the circumstances, is I'll remove the extractor button / spring, then I chamber a piece of measured brass (head to datum line shoulder). Then I'll add, cut to fit pieces of .0005" feeler gauges to a spic and span clean bolt face and chamber (I have a small stash just for this purpose). I chamber the piece of measured brass and continue adding .0005" feeler gauge shims until I'm at zero. It might sound extreme, and maybe it is, but it tells me with near precision where my shoulders are in relation to the chamber dimension. I magnetized them a little, it helps them stay in place during the process.

Put your thinking cap on, you should be able to build a reliable tool for this process. I almost bought the IT gauge, but the mixed reviews changed my mind.

GS

 

[Walkalong]

There are various ways to measure where the case shoulder is at, both home made and commercial. The new reloader has no need to try to get things within .0005, which is hard to do consistently. That is so close to a crush fit that the cases that resist sizing even slightly more than average will end up a crush fit. There is simply no need to cut it that close for anything less than a full blown accuracy rifle.

Bump your auto cases back an average .003 and call it good. Some will be less and some will be more, it's just the nature of the beast. Not all your brass will size exactly the same due to slight differences in spring back. Or just screw the die down to contact the shell holder, size your cases, and call it good. That works for many reloaders than one might think.

Leave the super tight brass to chamber fit to the more experienced reloaders, which you will be someday, but start more simply.

 

[notaglockfanboy]

IMO, by crushing the case in the chamber is the same as using your bolt action rifle as a press. It puts unneeded wear on the locking lugs. I neck size and bump the shoulders back after about the third or fourth firing, I also anneal after four firings. Extends brass life and helps accuracy. YMMV

 

[LTH]

Hey GS, pretty slick idea !

Walkalong , your right , I'm gonna keep it simple.
When I read and research hand loading , it seems like 95% of it is precision shooting.

Reading RCBS die instructions, my shoulder was pushed back way past an unfired case and then I read about excessive head space and then I'm down another trail.

I found a video on this guy working an ocw test from a starting load to max.
I was impressed.

And then found a video of the same guy showing how he reloads , prep etc.......

Very very simple and very tight groups.

He measures coal,
not from ogive .
All though , I'm gonna do the jive
Thanks guys for the advice !!!!!

 

[quartermaster]

LTH, i use my Hornady headspace gage all the time to set up my sizing die. I don't think you can use it to compare any Saami dimensions though. It is not meant for that nor sized for that purpose. It is great for comparing relative measurements and very repeatable for me. It has definately been one of the valuable tools added to my collection of reloading assets as well as the bullet comparator.

To get back to the original subject of this thread, I wouldn't suggest going with a crush fit. It seems to me you would be just asking for trouble at some point in time. I don't believe there is anything to gain over just setting back the shoulder .002 plus or minus. QM

 

[ironworkerwill]

I have a minimum match chamber on my target rifle and I have set the headspace up on minimally sized and annealed brass. I have virtually no head space but its not a "crush" fit. It shoots more accurately than I can. It took a while to determine when I felt a slight drag or a good snug fit, I feel very little resistance while chambering and no one notices it while firing the rifle.

 

[LTH]

y

Member

*

*

Join Date: December 22, 2014

Location: Kentucky

Posts: 341

IMO, by crushing the case in the chamber is the same as using your bolt action rifle as a press. It puts unneeded wear on the locking lugs. I neck size and bump the shoulders back after about the third or fourth firing, I also anneal after four firings. Extends brass life and helps accuracy.*

Yeah ! That doesn't sound good at all ! Using the bolt as a press .

 

[gamestalker]

I wasn't implying it's necessary to get my brass to within .0005", what I was stating is with a new rifle or a chamber I haven't loaded for yet, that this method works for me to determine where zero is, which tells me how far to bump the shoulder for that rifle.

GS

 

[LTH]

To get back to the original subject of this thread, I wouldn't suggest going with a crush fit. It seems to me you would be just asking for trouble at some point in time. I don't believe there is anything to gain over just setting back the shoulder .002 plus or minus. QM

________________

How far back , factory demension?

 

[taliv]

i haven't really put a ton of thought into it, but the more you size, the more room there is and the more room there is, the more your case will lay in the bottom of the chamber, causing your bullet to be very slightly off axis to the bore at the throat. i speculate that a crush fit, while bad for so many other reasons, could have the sole virtue of properly aligning the bullet so that it goes in more straight. i think the only further improvement required would be to have the case head centered on the bolt face instead of laying on the bottom.

maybe not though. i probably shouldn't try to think about geometry past my bedtime

 

[Clint M]

I enjoy reading these post as you can see new hand loaders rely starting to understand what they are trying to accomplish when sizing brass. I shoot for .002"on bolt guns as mentioned above springback dirt, grease, oil carbon etc also you can gall your bolt lugs if any grit or dirt is on them when chambering brass that is tight.

Now take a look at what your full length die does to your neck, measure the neck on some full length sized cases, then remove expander ball/stem and size a couple of cases. Most dies size the neck down way to much, still I use FL dies for everything. Even on my bench guns that see no hunting work I bump the shoulder back until the case chambers easy then a bit more for all the things mentioned above. I have seen no accuracy difference between sized brass (shoulder to case head) or very tight fitting compared with sized brass that easily chambers.

I love the Hornady headspace comparator I also use their bullet comparator.

 

[quartermaster]

LTH, not from a factory load, but from fired case. Upon working up loads, I will usually set back from my longest case.

You will find much better brass life setting the shoulder back a small amount vs. drastic FL sizing and fired formed brass always shoots moer accurately fo me.

QM

 

[JimKirk]

I size all my bolt action cartridges to a tight fit ... by tight I don't mean gorilla twist tight .... just a faint hint that the cartridge is fitting into the chamber with out much of any slop ... I don't have to force the bolt handle down, but I do feel a slight resistance at the end of the bolt stroke.... as someone above said ... that centers the cartridge into your chamber ... it also help case life by not allowing artificial headspace to be created when you over size your brass ... I have .25/06 brass that has 20 or more firing at full load levels .... that is because the brass has very little to stretch ...

One of the first things I see now days is for the reloader to get a chamber gauge .... you don't need a gauge unless you are loading for a AR or other semi auto ... with a bolt action the chamber should be your gauge ... if you fit your cartridge to the chamber... case life will be long and the proper fit goes a long ways toward accuracy...

Crush fit ... NO .... but snug YES !

 

[LTH]

I really appreciate all the help , this has been eye opening.
I have read so much on this topic and you guys have helped me to understand better.

I'm gonna put some notes in my book and when it comes time to resize ,I'll have it.

I'm starting out with Nosler brass and their components with their # 7 manual.

Many thanks !

 

[Snyper]

Reading RCBS die instructions, my shoulder was pushed back way past an unfired case and then I read about excessive head space and then I'm down another trail.

That's because Remington is giving instructions that will make the cases fit any rifle with that chambering.

After fireforming, if the loads will be used in the same rifle, you don't use the same beginning set-up

 

[LTH]

Thanks Snyper

 

[gamestalker]

What JimKirk said, slight resistance. Make sure the bolt, chamber, and brass are clean, helps avoid a false fit.

GS

 

[fguffey]

The 2.0395" far right is the same position as a new unfired case.

The 1st and 2nd chamber pretty good.

first I would have made an attempt to determine the length of the chamber from the shoulder to the bolt face. SAMMI says "2.048 minimum and 2.058 maximum". If your measurements are accurate you do not have a case that is close to fitting with a crush.

In my opinion fitting with a crush is a bad habit. Then there is 'bump', bump sounds too much like an accident. I do have bump presses, I also have presses that do not bump. All of my cam over presses are bump presses. My presses that do not bump are not cam over presses.

I am the big fan of comparators, I compare fired cases with cases that have not been fired and are of minimum length, that is the same as full length sized, new, over the counter ammo. The difference in length indicates the effect the chamber had on the case when fired.

F. Guffey

 

[LTH]

um". If your measurements are accurate you do not have a case that is close to fitting with a crush.

Thanks for the reply , my smoked shoulders tell me different, unless I'm missing something.

Are they snug fit ?
I used the wrong term in the title , should have wrote slight .

I posted the pics in hopes that someone would give me an idea what's going on ,unless what I did doesn't mean anything!