When Do You Trim Cases?

BarnardP · October 31, 2013, 02:05 PM

Greetings,

I've just stumbled upon this excellent forum, hope you don't object to my first post being a question...

I've just purchased a Wilson case trimmer (nice little piece of kit) mainly for the .308 I shoot in F/TR.

Should I be using this to return cases to 2.006" before or after neck sizing?

Thanks in advance,

Mick.

**Unclenick** · October 31, 2013, 02:17 PM

Welcome to the forum.

The SAAMI spec for .308 Win case length is 1.995"-2.015", and the military spec is 2.000"-2.015". Anywhere in there is fine. The 2.005" trim-to length is just the mid-point between the ends of the SAAMI spec. You don't need to trim again until a resized case exceeds 2.015" unless you are crimping, in which instance uniform length is needed for uniform crimp pressure and so has you trimming every load cycle.

With neck sizing-only there is very little case growth, so, assuming you don't crimp, you may have a long wait before you have to do it again. Most case growth occurs during a full-length resizing cycle. (See exaggerated illustration below.)

oldpapps · October 31, 2013, 02:53 PM

Welcome.

Unclenick knows.

As for me, I don't normally never trim any straight walled cases. However, I am compulsive and trim every one of my bottle necked cases. Do each and every one need it? No and during the process I see many that are never touched. I still run each case.

Trim after sizing. I think there is more stretching of the case during the pulling of the expanding plug than at any other time. I want greater uniformity.

Load with care,

OSOK

Sierra280 · October 31, 2013, 03:00 PM

I trim every time. Keeping the case necks the same length means equal bearing surface holding the bullet in each case-thus it helps minimize inconsistency (isn't that the goal of handloading?)

adrians · October 31, 2013, 04:55 PM

Timely thread , i'm in the process of trimming 250 once fired range pick-ups .

I have a Wilson trimmer and holders but I find it quicker to use a trim die .

BTW, it gives me a constant 2.015

4runnerman · October 31, 2013, 05:42 PM

Im with Sierra here. Every time. Range pick up you say. If your shooting for accuracy,start sorting and weigh the cases.

adrians · October 31, 2013, 06:09 PM

I agree with you 4runnerman consistency matters when reloading, all the "pick-ups" are all Federal cases , no mixed headstamps .

They were full length sized ,fire formed and now it's trim time.

Neck size only thereafter.

cw308 · October 31, 2013, 06:59 PM

Federal cases are alittle thicker than most, my have to reduce powder charge by .5 from load listings. I also neck size an partial neck size.keep my oal to 2.010,also clean outside of necks with 0000 steel wool,inside with bronze brush,uniform primer pockets & clean flash hole,debur inside flash hole once on all casings. I enjoy it all from shooting your own to reloading, great sport.

adrians · October 31, 2013, 07:41 PM

Quote:

Federal cases are alittle thicker than most, my have to reduce powder charge by .5 from load listings. I also neck size an partial neck size.keep my oal to 2.010,also clean outside of necks with 0000 steel wool,inside with bronze brush,uniform primer pockets & clean flash hole,debur inside flash hole once on all casings. I enjoy it all from shooting your own to reloading, great sport.

,,

Pretty much do all that sans the 0000 wool part

No need to reduce my charges as I start low to begin with,, like 3.5 of bulls eye and a 120 grn cast

Jim243 · October 31, 2013, 08:01 PM

Pistol cases I do not trim, but I shoot only semi-auto. Revolver cases I always trim. Rifle cases get trimmed depending on if they need it. I measure all cases on this gauge:

It shows me which need to be trimmed and which don't. They are measured AFTER full length resizing, I do not use fire formed cases, neck sized only.

This saves a lot of time not resizing cases that don't need it. And shows if the case is getting too small (yes some do shrink).

Jim

Valornor · October 31, 2013, 08:22 PM

I trim every time, it can be a pain but it's also an important part of having accurate rounds. It can also be interesting to see what brand cases stretch more then others. Also it can be interesting to see after the second or third firing the cases don't need to be trimmed back as much. Again that varies with brand.

Always trim after your full length resize and not before. Personally I try and trim to the minimum every time.

Bart B. · October 31, 2013, 08:41 PM

I've trimmed my .308 Win. and 30 caliber magnum cases every 10 or so full length sizing cycles. They shorten a couple thousandths when fired with maximum loads, then grow a few thousandths full length sizing them It's about .001" growth per cycle. The .308 cases are kept between 2.000" and 2.010" as I've not seen any accuracy difference between the shorter and longer ones.

Waldog · November 1, 2013, 08:31 AM

Since I got my Giraud trimmer, I trim each time they are fired. HOWEVER, I certainly didn't do that before I got the Giraud.

I used to trim to minimum and hoped that the necks would split before I had to trim again.

jimbob86 · November 1, 2013, 08:50 AM

When do you trim?

Every time they are sized.

Waldog · November 4, 2013, 09:33 AM

Sorry, should have been more clear. I trim AFTER I resize the cases.

rebs · November 4, 2013, 09:42 AM

Quote:

Timely thread , i'm in the process of trimming 250 once fired range pick-ups .

I have a Wilson trimmer and holders but I find it quicker to use a trim die .

BTW, it gives me a constant 2.015
_

How do you use a trim die ?

reynolds357 · November 5, 2013, 08:51 PM

Every time I full length size.

ranchito457 · November 5, 2013, 11:47 PM

Rifle cases every time no matter what.Handgun-never no matter what..

RC20 · November 7, 2013, 01:35 PM

I don't do neck sizing (have not bought into it) and shoot a lot of 30-06.

I have a battery powered "Littlb Crow Gunworks) neck trimmber. Like the Gerrard but not as expensive and vialb option if not loading large quanties.

Easier to just run them all through than to check each one (after the re-size of course)

Quote:

Federal cases are a little thicker than most, my have to reduce powder charge by .5 from load listings. I also neck size an partial neck size.keep my oal to 2.010,also clean outside of necks with 0000 steel wool,inside with bronze brush,uniform primer pockets & clean flash hole,debur inside flash hole once on all casings. I enjoy it all from shooting your own to reloading, great sport.

I have not checked the capacity but weight wise the case runs around 200 gr in 30-06 (sans primer) . RP avg is 195 and Hornady and Nossler which is supposed to be premier brass is down in the 180 gr range (and my brother was having case split issues, he gave to me as I run lighter loads and will see how they do with that)

BarnardP · November 7, 2013, 03:22 PM

Thanks all, I appreciate you taking the time to answer.

**Unclenick** · November 7, 2013, 06:57 PM

RC20,

An old rule of thumb is -0.06 to -0.07 grains of powder for each grain of brass.

105gr · November 7, 2013, 07:25 PM

RC20....what do you mean "havent bought into neck sizing"?

BumbleBug · November 7, 2013, 07:34 PM

I'm a big believer in using chamber length gauges to determine just what the max is for individual rifles using bottle neck cartridges. Sinclair has a video showing how they work.

Code:

http://www.youtube.com/watch?v=JKnXJxaAw2U

A quick check of a sized case with a dial caliper keeps me comfortable that I don't have a dangerous situation for my particular rifle. Within acceptable tolerances, I usually set the trimmer to the shortest case when I trim a batch. Straight wall pistol cases I just trim to SAAMI spec's when I do my initial prep.

FWIW...

...bug

Jay24bal · November 7, 2013, 10:14 PM

My rifle brass (all bottleneck cases) get trimmed every time I reload them, regardless of full length or just a neck sizing.

I have yet to ever trim a pistol case, granted the most any of my cases have been reloaded is 7 times.

Brotherbadger · November 8, 2013, 04:06 AM

Quote:

When do you trim?

Every time they are sized.

Agreed. With rifle it is just part of my routine. I don't even think about it, i just do it. With pistol, i don't bother.

October 31, 2013, 02:05 PM	#1
BarnardP Junior Member Join Date: October 13, 2013 Location: US of England Posts: 6	When Do You Trim Cases? Greetings, I've just stumbled upon this excellent forum, hope you don't object to my first post being a question... I've just purchased a Wilson case trimmer (nice little piece of kit) mainly for the .308 I shoot in F/TR. Should I be using this to return cases to 2.006" before or after neck sizing? Thanks in advance, Mick.

October 31, 2013, 02:17 PM	#2
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Welcome to the forum. The SAAMI spec for .308 Win case length is 1.995"-2.015", and the military spec is 2.000"-2.015". Anywhere in there is fine. The 2.005" trim-to length is just the mid-point between the ends of the SAAMI spec. You don't need to trim again until a resized case exceeds 2.015" unless you are crimping, in which instance uniform length is needed for uniform crimp pressure and so has you trimming every load cycle. With neck sizing-only there is very little case growth, so, assuming you don't crimp, you may have a long wait before you have to do it again. Most case growth occurs during a full-length resizing cycle. (See exaggerated illustration below.) __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

October 31, 2013, 02:53 PM	#3
oldpapps Senior Member Join Date: September 22, 2011 Location: Middle America Posts: 518	Welcome. Unclenick knows. As for me, I don't normally never trim any straight walled cases. However, I am compulsive and trim every one of my bottle necked cases. Do each and every one need it? No and during the process I see many that are never touched. I still run each case. Trim after sizing. I think there is more stretching of the case during the pulling of the expanding plug than at any other time. I want greater uniformity. Load with care, OSOK Last edited by oldpapps; October 31, 2013 at 03:16 PM.

October 31, 2013, 04:55 PM	#5
adrians Senior Member Join Date: August 6, 2010 Location: mountain view ,ar. Posts: 184	Timely thread , i'm in the process of trimming 250 once fired range pick-ups . I have a Wilson trimmer and holders but I find it quicker to use a trim die . BTW, it gives me a constant 2.015 __________________ instant karma's gonna get you , knock you right in the face...... j.w.l.

October 31, 2013, 05:42 PM	#6
4runnerman Senior Member Join Date: January 16, 2010 Location: Minnesota Posts: 3,577	Im with Sierra here. Every time. Range pick up you say. If your shooting for accuracy,start sorting and weigh the cases. __________________ NRA Certified RSO NwCP- Performance Isn't Optional

October 31, 2013, 03:00 PM	#4
Sierra280 Junior member Join Date: July 29, 2013 Location: Gardnerville, NV Posts: 569	I trim every time. Keeping the case necks the same length means equal bearing surface holding the bullet in each case-thus it helps minimize inconsistency (isn't that the goal of handloading?)

October 31, 2013, 06:09 PM	#7
adrians Senior Member Join Date: August 6, 2010 Location: mountain view ,ar. Posts: 184	I agree with you 4runnerman consistency matters when reloading, all the "pick-ups" are all Federal cases , no mixed headstamps . They were full length sized ,fire formed and now it's trim time. Neck size only thereafter. __________________ instant karma's gonna get you , knock you right in the face...... j.w.l.

October 31, 2013, 06:59 PM	#8
cw308 Senior Member Join Date: September 2, 2010 Location: Plainview , Long Island NY Posts: 3,863	Federal cases are alittle thicker than most, my have to reduce powder charge by .5 from load listings. I also neck size an partial neck size.keep my oal to 2.010,also clean outside of necks with 0000 steel wool,inside with bronze brush,uniform primer pockets & clean flash hole,debur inside flash hole once on all casings. I enjoy it all from shooting your own to reloading, great sport.

October 31, 2013, 08:01 PM	#10
Jim243 Senior Member Join Date: January 5, 2009 Location: Just off Route 66 Posts: 5,067	Pistol cases I do not trim, but I shoot only semi-auto. Revolver cases I always trim. Rifle cases get trimmed depending on if they need it. I measure all cases on this gauge: It shows me which need to be trimmed and which don't. They are measured AFTER full length resizing, I do not use fire formed cases, neck sized only. This saves a lot of time not resizing cases that don't need it. And shows if the case is getting too small (yes some do shrink). Jim __________________ Si vis pacem, para bellum

October 31, 2013, 08:22 PM	#11
Valornor Senior Member Join Date: March 18, 2010 Location: Orem, Utah Posts: 244	I trim every time, it can be a pain but it's also an important part of having accurate rounds. It can also be interesting to see what brand cases stretch more then others. Also it can be interesting to see after the second or third firing the cases don't need to be trimmed back as much. Again that varies with brand. Always trim after your full length resize and not before. Personally I try and trim to the minimum every time.

October 31, 2013, 08:41 PM	#12
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	I've trimmed my .308 Win. and 30 caliber magnum cases every 10 or so full length sizing cycles. They shorten a couple thousandths when fired with maximum loads, then grow a few thousandths full length sizing them It's about .001" growth per cycle. The .308 cases are kept between 2.000" and 2.010" as I've not seen any accuracy difference between the shorter and longer ones.

November 1, 2013, 08:31 AM	#13
Waldog Senior Member Join Date: March 28, 2007 Location: SOCAL Posts: 359	Since I got my Giraud trimmer, I trim each time they are fired. HOWEVER, I certainly didn't do that before I got the Giraud. I used to trim to minimum and hoped that the necks would split before I had to trim again. __________________ I am the Christian Conservative that CNN warned you about!! “Socialism is the philosophy of failure, the creed of ignorance and the gospel of envy.” Winston Churchill

November 1, 2013, 08:50 AM	#14
jimbob86 Junior member Join Date: October 4, 2007 Location: All the way to NEBRASKA Posts: 8,722	When do you trim? Every time they are sized.

November 4, 2013, 09:33 AM	#15
Waldog Senior Member Join Date: March 28, 2007 Location: SOCAL Posts: 359	Sorry, should have been more clear. I trim AFTER I resize the cases. __________________ I am the Christian Conservative that CNN warned you about!! “Socialism is the philosophy of failure, the creed of ignorance and the gospel of envy.” Winston Churchill

November 5, 2013, 08:51 PM	#17
reynolds357 Senior Member Join Date: December 10, 2012 Posts: 6,165	Every time I full length size.

November 5, 2013, 11:47 PM	#18
ranchito457 Senior Member Join Date: April 2, 2013 Location: Manhattan,Illinois Posts: 179	Rifle cases every time no matter what.Handgun-never no matter what..

November 7, 2013, 03:22 PM	#20
BarnardP Junior Member Join Date: October 13, 2013 Location: US of England Posts: 6	Thanks all, I appreciate you taking the time to answer.

November 7, 2013, 06:57 PM	#21
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	RC20, An old rule of thumb is -0.06 to -0.07 grains of powder for each grain of brass. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

November 7, 2013, 07:25 PM	#22
105gr Member Join Date: November 6, 2013 Location: Groveport, OH...U.S. A. Posts: 29	RC20....what do you mean "havent bought into neck sizing"? __________________ TEAM HILLBILLY

November 7, 2013, 07:34 PM	#23
BumbleBug Senior Member Join Date: March 11, 2013 Location: Near Heart of Texas Posts: 870	Sinclair Chamber Length Gauges I'm a big believer in using chamber length gauges to determine just what the max is for individual rifles using bottle neck cartridges. Sinclair has a video showing how they work. Code: http://www.youtube.com/watch?v=JKnXJxaAw2U A quick check of a sized case with a dial caliper keeps me comfortable that I don't have a dangerous situation for my particular rifle. Within acceptable tolerances, I usually set the trimmer to the shortest case when I trim a batch. Straight wall pistol cases I just trim to SAAMI spec's when I do my initial prep. FWIW... ...bug

November 7, 2013, 10:14 PM	#24
Jay24bal Senior Member Join Date: December 13, 2011 Location: Cleveland, OH Posts: 735	My rifle brass (all bottleneck cases) get trimmed every time I reload them, regardless of full length or just a neck sizing. I have yet to ever trim a pistol case, granted the most any of my cases have been reloaded is 7 times. __________________ I like guns. Once Fired Brass, Top quality, Fast shipping, Best prices. http://300AacBrass.com/ -10% Coupon use code " Jay24bal "