Length & Trimming of old .30-30 brass questions

cappy102 · Jun 19, 2019

I'm a new member and will post an introduction in the proper place, if necessary, but have been following this thread with interest. My experience reloading is limited to just the last couple of years, and there are questions aplenty. To get to it...recently I inherited a pile of my Dad's old reloads. Old as in late seventies.

The cartridges that I have a question about are .30-30, a mixed bag of R-P and Win brass. Once dis-assembled, I sorted the headstamps and measured the cases. Out of 60 cases, one measured 2.040", one 2.030", and all the rest were consistently 2.024" +/- a negligible amount. No idea how many firings they've seen.

All this got me curious, so I measured some factory .30-30 ammo I have on hand. The Rem 170gr 'Core-Lokt' cases measure 2.020". The Win 150gr 'Powerpoint' cases measure 2.026".

What are the published trim-to lengths based on? Speer, Lyman, and Lee all have different lengths for this cartridge in their loading manuals, but all are over 2.028".

Hooda Thunkit · Jun 19, 2019

I don't know for certain on what the "trim to" length is based, but I suspect it's based on SAAMI specs.

For instance, Lee trimmer states "trim to length 2.019 - 2.039"
https://leeprecision.com/gage-holder-30-30-win.html

That's a .020" span.

You didn't ask, but here is what I would do with that brass.
Deprime, clean, inspect.
Full-length size.
Trim it all to a single length, whichever length makes them all the same.
Chamfer, deburr.
Sort by headstamp, load and shoot.

I would be more concerned about brass too long, than brass too short.

Reloadron · Jun 19, 2019

Speer #12 Suggested Trim To is 2.0295" so we can call it 2.030"
Hornady 9th Edition Suggested Trim To is 2.029"

Finally looking at the SAAMI Specifications (Page 96) reflects a case length of 2.0395" -0.0200" so using SAAMI specifications any case length between 2.0395 and 2.0195 is within specifications. Split the max and min delta for 0.010 and add that to the min of 2.0195 and we get the 2.0295" we see above so I would just call it at about 2.030" placing you right about midway between min and max and just make them all uniform within the range.

Ron

Slamfire · Jun 19, 2019

Trim length only real importance for the reloader is keeping the case neck out of the throat. While this is a 30-06 case, you can see the clearance between the throat taper and the case neck

You don't want the case neck to be pinched in the throat. That is about it. I have accidentally trimmed cases much below minimum, and as long as the case held the bullet, the bullet went downrange and generally impacted close to where it was aimed.

As for 30-30's, I don't own enough to know if there really ever was a standard SAAMI chamber used by manufactuerer's. My Marlin 336 has a huge chamber and the bullet has to jump two tenth's of a inch before it touches the rifling. I still trim my 30-30 brass, but I doubt I will ever have a case neck so long that it will pinch the bullet.

Don't sweat the tiny stuff. Set a trim length that you like, maybe it has all the digits of your birthday, or is a number easily remembered, and just use that.

lightman · Jun 19, 2019

Welcome Aboard! I think its cool that you are trying to use some of your Dad's old stuff!

The old chart that I have had forever has a suggester trim to length of 2.028. A 30-30 case has a long neck so I would be comfortable trimming your brass .001 shorter than your shortest case and loading them.

Cuz70 · Jul 12, 2019

I'd do as the lightman said .Load em up.

FROGO207 · Jul 12, 2019

The main thing about this cartridge is that you do need a roll crimp to keep the bullet from collapsing back into the case under recoil in a tubular magazine. If all the brass are all the same length then roll crimping will be consistent and you will not be adjusting your die all the time. Also the longer the neck the more neck tension as long as it does not get pinched as stated above. Different brands of ammo use bullets with canalures in different locations and trim their brass accordingly. So pick a length and make them all the same and note that length in your reloading log.

Patocazador · Jul 12, 2019

Most of the .30-30 bullets you acquire will have a cannelure. Decide on a bullet and COAL and trim to the length that allows roll crimping in the cannelure. This procedure will provide the best overall solution to your problem.

Charlie98 · Jul 12, 2019

FROGO207 said:
The main thing about this cartridge is that you do need a roll crimp to keep the bullet from collapsing back into the case under recoil in a tubular magazine.

Just FYI, Cappy, the .30-30 brass has a very thin neck... trimming them all to the same length and getting an even crimp is critical. I've crushed more .30-30 cases than all the other cartridges I load for combined... because I put too much crimp into them, or they were mix-master lengths. A good crimp is good, but you don't have to put the patented Charlie98 Death Grip Crimp in there...

Length & Trimming of old .30-30 brass questions

cappy102

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Hooda Thunkit

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Reloadron

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Slamfire

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lightman

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Cuz70

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FROGO207

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Patocazador

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Charlie98

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