case length question

M

mendozer

New member
I reloaded a batch 2 years ago and had great results. Last year I bowhunted. This year gonna do elk with rifle.

So I get my cases and prep them all the same way but I'm getting sporadic length readings.

Here's my process:
Deprime
sonic cleaner
lube
resize and check headspace/length with Lyman gauge/trim if needed
sonic cleaner
prime
load!

I'm getting lengths from 2.492-2.503 throughout the lot, despite not only using the length gauge but also trimming it down (to the most that I can by the way using my Lee .30-06 trimming die).

My books say 2.484 is the max, yet I've seen 2.494 online as well.

I can't figure out why I'm getting sporadic readings.

I'm using my caliper which is very precise too. So it might be the tiny movement of the case while between the caliper arms

thoughts?
 
We are talking about the 30/06? The 2.494 is the maximum case length for most reloaders. I add additional chamber length from the shoulder to the bolt face; that puts me outside of most rloaders. And then there is a recommended 'trim to length'; that would be .010" shorter than maximum case length.

I have no clue what a Lee case trim die is, I have RCBS case trim/form dies and I have found there is no way to trim a case more accurately than the RCBS trim/form die; problem, the die and press have threads. Threads do not lock me up because one of the first tools I stack up in front of me when reloading is the feeler gage.

F. Guffey
 
There are all kinds of trimmers out there. I can verify that you should stay clear of the (Old RCBS collet type holders). Depending on the case rim diameter and width the trimmed cases can very a lot in length.

Lyman makes carbide expander rods that they claim will slide through the neck with less resistance. That might be what you are looking for. Used with Decaping or Neck Sizing.

Of course trim after sizing.
 
The brass your sizing , are they all the same brand ? I also have the Lyman case gauge, for measuring found the RCBS Precision Mic very easy to use. Your brass is clean so I would guess it's how your setting up your F/L sizing die. I just posted a question on a Go Gauge, helped me find what my chamber size is. I use the standard RCBS F/L die with the Redding competition shell holder set of 5 , very helpful in sizing accurately. I can now size all my cases to .0015 case space. Once you size all your cases the same length from the base to the datum line, trimming your cases to the same OAL, I trim all my cases .005 from max. You can start from the shortest set your cutter to that length , having all your cases trimmed to the same length.
 
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2.484" is the trim-to length. Like F. Guffey says, 2.494" is the max case length.
Lock your calipres at 2.494" and use it as a case length gauge to check 'em all. Then trim only the cases that are too long. Doesn't hurt to set the ones that are less than 2.494" already aside and check 'em with the calipres at 2.484", but anywhere between those numbers is fine. SAAMI tolerance is actually 2.494" -.020" though. So a tick under 2.484" is fine too.
Your Lee .30-06 trimming die will do nicely. You will still have to chamfer and deburr.
"...what a Lee case trim die is..." http://leeprecision.com/quick-trim/
 
ok thanks for the tips. I'll try the locked caliper thing. As for my F/L sizing die, it's a Hornady. So you're saying I might be resizing it with improper spec?
 
That's why I asked. You shouldn't mix brass when working up a load. One time I thought all brass was the same. Federal brass is much thicker, causing less volume, would be a problem with hot loads. Should reduce load by 1 grain from listed loads. Once you know your chamber size, you can size for minimum case space in your chamber. I think you have to know if your fired cases are getting wider, shorter or longer. Test with one brand of brass at a time. They might fire form differently in your chamber.
 
ok I'll measure my last batch of reloaded cases. They were once fired Federals too I believe. So just federal has this issue? 1 full grain makes a big differnce for grouping too. I only have once reloaded batch under my belt, but the best performing group I had was my highest load.
 
Never used PPU or S&B. Winchester & Remington are about the same, thinner then Federal. I saw there was a difference when I added powder, using IMR 4064 my powder on the Win. & Rem. brass was much lower in the case then Federal. Asked the question to this forum & just as I expected federal was thicker. You probably will hear from your post about the other two cases. I know military cases tend to be on the thick side. For hunting, on the high side of the load chart is fine. Try to stay away from max. Especially using a thicker case. I'll check back later, heading to the range. Chris
 
OK so my last batch was all Federal (Fusion ammo to be specific). This round of cases has some remington, federal and allot of S&B and PPU. I couldn't discern a thickness difference with my caliper. I registered them all at .015 thickness at the necks.

My fired federals (now two firings since factory and 1 reload) was still at a length of 4.490 or less, none were over. Everything I resized this time around was over. I didn't change any setting on my die.
 
Maybe I'll group the federals together to save as one brass type and the PPU as another. I'll toss the S&B and few remingtons.

As far as new, midway was winchester pretty cheap but they have sketchy reviews. Might be worth it for lapua since people say they reload many times.
 
FWIW last year for chamber size I just loaded a bullet into a shell to the lands, backed off .030 if memory serves, and that was my COAL
 
Mr. Guffey makes a VERY good point!
If you have 0.0015" head space, then you need to reduce length by about 0.002" to keep from jamming mouth of case into the end of the brass chamber.

CW makes a good point about Datum Point chamber sizing,
Getting that case head (head stamp end) to the datum point on the shoulder gets the case to fit the chamber HEAD SPACE,
Then, and only then, do you trim for case length...

The 'Neck' can be trimmed a little 'Short' since all the neck does is keep the bullet centered in the case, and hopefully the bore, but not all chambers are centered with the bore... That's another thread entirely.

Generally, with longer range single shot rifles, you only want to 'Bump' the brass back enough it will fit into the chamber properly.
Sometimes you/the press wins, sometimes the brass wins and won't bump back where you want it.
Again, that's another thread entirely... Not all presses are created equal...
 
Mandozer
What make & action is the rifle ? I shoot a Rem.700. On the Remington s it's easy to strip the bolt and only use the bolt body to chamber a sized case. When the round is fired , the case expands & springs back .001 the case get wider making it shorter. Picture the shape of the chamber, we want to get the case to be the exact shape & size from the shoulder to the bolt face. I never knew the size until I ordered a Go Gauge, installed it in my chamfer, the bolt closed without any resistance. Cut a piece of .002 off the feeler gage and placed it on the back of the Go Gauge , the bolt didn't close. Tried .001 closed. Installed the Go Gauge in my RCBS Precison Mic to get a measurement added .001 Now I know how long my case should be. I'll size a case , check it in the mic. & in my chamber. Sounds like a lot to do but its not. The .015 neck thickness, did you measure the thickness at different areas of the case ,let's say 12 & 6 o'clock on the neck. .015 is thick . l found Rem. & Win. brass.thinner. I like the thicker brass. Size with the expander ball, lube the inside of the case neck with a Q-tip. Remember to remove all the lube , inside and out before adding powder. I'm lucky , one of my shooting buddies doesn't reload, gives me all his brass. Once you have your case sized for your chamber then trimmed to proper length, then you can seat the bullet to what works best for your rifle from the ogive, not AOL, not as accurate. The Precision Mic. does it both, measures from the case base to datum line also case base to ogive. Sorry for the long post.
 
I do resize with the full size die from Hornady with the ball inside.

As far as these gauges you mention I have the Lyman gauge that has an upper and lower limit for case length on the top and inside has the headspace measurement. Problem is I can barely feel the top of the case poking out over the upper limit because it might be off by 4/1000 inch.

For whatever reason, I also wasn't able to trim my cases any shorter. My Lee QuickTrim is set to the max and I couldn't take any more off. It's a 30-06 specific die and has .006 max trim potential.
 
mendozer
The Lyman case gauge will give you max. & minimum case length, if checked with your calipers while case is in the Lyman die , you can get the measurement. I like the Precision Mic. makes both case & bullet measurements very accurate & easy to use. I don't know the Lee Quick trim , will check it out & get back to you, I would think it should cut lower then max.
 
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mendozer
Specs for the 30-06 trim lengths 2.474 to 2.494 A trim to 2.484 is right in the middle, which is a safe average trim. Some chambers could be longer. You want the case to have enough space to allow the bullet to exit the case , without the end of the case being at the end of the chamber with no room to release the bullet , causing pressure problems. You may have a slightly longer neck in the chamber, just trim it to the setting on the Lee Quick trimmer.
Is there a black adjustment ring on your cutter to trim lower then max.? What is your trim length ? What rifle are you shooting ?
 
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I have a savage 111. Yes my quick trim has the black dial. I just took one of the soon to be trashed S&Bs and trimmed one from 4.502 to 4.489. I may have had my dial on the wrong side of the .006 spectrum. However, that clearly trimmed more than .006.

I can't remember my process for figuring out headspace last year other than using the gauge for shoulder width, then running everything through the quick trim. Other than that I used my bullet comparator set to measure OAL after backing off the lands a certain amount
 
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