Someone told me, and I'm pretty new to reloading, that I don't need to trim my brass every time, unless I am shooting a bolt gun and going for accuracy....My rounds are just for plinking in my AR15 and Mini-14. I do trim my .338 LM rounds, as I am going for extreme accuracy and consistent loads. I am using just a mix match of brass that me and some buddies have collected over the last few years....like I said, they are mostly for plinking and varmint popping.....thanks for the input....also has anyone used the Hornady progressive "lock and load" press for 5.56/.223....I have been using 2 single stage presses, but have the progressive press on order with the shellplates I need...Thanks for the input....
5.56mm/.223 Trimming
- Thread starter yankone388
- Start date
Re: 5.56mm/.223 Trimming
Your buddy is right, but that is not the whole picture. Consistent trim legth is not likely to be noticed even in a bench rest rifle, so no it is not required for accuracy. The danger in a "junk pile" of brass is that you may actually have a piece that is longer than your shortest chamber will accept, potentially crimping the case mouth against the seated bullet and causing dangerously high pressures on firing. I hate nothing more than a pile of range brass, even when loading "go bang" .45 ammo. Case length variations make it impossible to get a uniform mouth expansion or uniform crimp.
Sorry, you didn't ask my opinion on scraping together a pile of brass and all the pitfalls associated.
A realistic answer is that if you shoot where others shoot, you may pick up a piece of brass that has been through he__ and is actually dangerous in your chamber. So, if there is a chance you're going to collect a piece of range brass you have to measure every piece or trim every piece to be sure. One way to avoid this is to "Sharpie" a color stripe of your choice across all your known safe length brass and check for your stripe when you pick up your empties. I use this at matches not because I'm afraid some guy will get my brass, but rather because I'm afraid I'll get some of his.
Hope this helps.
Randy
Your buddy is right, but that is not the whole picture. Consistent trim legth is not likely to be noticed even in a bench rest rifle, so no it is not required for accuracy. The danger in a "junk pile" of brass is that you may actually have a piece that is longer than your shortest chamber will accept, potentially crimping the case mouth against the seated bullet and causing dangerously high pressures on firing. I hate nothing more than a pile of range brass, even when loading "go bang" .45 ammo. Case length variations make it impossible to get a uniform mouth expansion or uniform crimp.
Sorry, you didn't ask my opinion on scraping together a pile of brass and all the pitfalls associated.
A realistic answer is that if you shoot where others shoot, you may pick up a piece of brass that has been through he__ and is actually dangerous in your chamber. So, if there is a chance you're going to collect a piece of range brass you have to measure every piece or trim every piece to be sure. One way to avoid this is to "Sharpie" a color stripe of your choice across all your known safe length brass and check for your stripe when you pick up your empties. I use this at matches not because I'm afraid some guy will get my brass, but rather because I'm afraid I'll get some of his.
Hope this helps.
Randy
Re: 5.56mm/.223 Trimming
I trim every load. My brass after firing was inconsistant enough in length I decided to trim. I had a range of 20 thousandths in length.
I trim every load. My brass after firing was inconsistant enough in length I decided to trim. I had a range of 20 thousandths in length.
Re: 5.56mm/.223 Trimming
I recommend you sort your brass by brand. Different brand equals different capacity! Throw out all bad brass. Trim everything. Find which one works for you. One does not have to trim every time. Only when it exceeds max case trim dimensions.
I recommend you sort your brass by brand. Different brand equals different capacity! Throw out all bad brass. Trim everything. Find which one works for you. One does not have to trim every time. Only when it exceeds max case trim dimensions.
Re: 5.56mm/.223 Trimming
If you are concerned with trimming, another option is the RCBS x-die. It requires you to do an initial trim on all of your brass. After that though, it uses a special expander mandrel and keeps the brass from lengthening. I have seen several positive reviews on it, but have not tried it myself.
I trim my 556 brass everytime on a progressive press with a dillon trimmer, so my sizing and trimming is done in one step.
If you are concerned with trimming, another option is the RCBS x-die. It requires you to do an initial trim on all of your brass. After that though, it uses a special expander mandrel and keeps the brass from lengthening. I have seen several positive reviews on it, but have not tried it myself.
I trim my 556 brass everytime on a progressive press with a dillon trimmer, so my sizing and trimming is done in one step.
Re: 5.56mm/.223 Trimming
I trim every time, but Im using a giraud trimmer so its actually fun trimming brass.
I trim every time, but Im using a giraud trimmer so its actually fun trimming brass.
Re: 5.56mm/.223 Trimming
The reason that the trim specs in load books are so phony is that the real trim length is when the distance from the shoulder to the mouth of the case is longer than from the shoulder to the mouth of the chamber.
The book want to spec a distance from case base to case mouth.
So a big fudge factor is thrown in.
The smartest thing to do is keep brass segregated to one rifle, and just push the shoulder back .001". Then the brass will grow a lot less.
Letting the die bump the shell holder can lead to trimming every time.
The reason that the trim specs in load books are so phony is that the real trim length is when the distance from the shoulder to the mouth of the case is longer than from the shoulder to the mouth of the chamber.
The book want to spec a distance from case base to case mouth.
So a big fudge factor is thrown in.
The smartest thing to do is keep brass segregated to one rifle, and just push the shoulder back .001". Then the brass will grow a lot less.
Letting the die bump the shell holder can lead to trimming every time.
Re: 5.56mm/.223 Trimming
Thank you all for the info....I think if I trim one time and keep MY brass Ill have to trim a lot less....just for 5.56mm.....I tend to trim my .338LM to keep it consistent at matches and for XLR shooting.
Thank you all for the info....I think if I trim one time and keep MY brass Ill have to trim a lot less....just for 5.56mm.....I tend to trim my .338LM to keep it consistent at matches and for XLR shooting.
Re: 5.56mm/.223 Trimming
Different guns have a different amount of space cut into the chamber in terms of case (neck) length. In other words, what might be too long for one gun will be fine for another. The SAAMI 'max' length in your reloading manual is intended to make sure the case will fit into any gun safely. The chamber in your gun most likely will be longer than that.
Sinclair sells this <span style="color: #FF0000">$6 item</span> that lets you measure your own chamber to see what is the true max length for your gun. Then trim several thou shorter than that.
Different guns have a different amount of space cut into the chamber in terms of case (neck) length. In other words, what might be too long for one gun will be fine for another. The SAAMI 'max' length in your reloading manual is intended to make sure the case will fit into any gun safely. The chamber in your gun most likely will be longer than that.
Sinclair sells this <span style="color: #FF0000">$6 item</span> that lets you measure your own chamber to see what is the true max length for your gun. Then trim several thou shorter than that.
Re: 5.56mm/.223 Trimming
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: OldTex</div><div class="ubbcode-body">Different guns have a different amount of space cut into the chamber in terms of case (neck) length. In other words, what might be too long for one gun will be fine for another. The SAAMI 'max' length in your reloading manual is intended to make sure the case will fit into any gun safely. The chamber in your gun most likely will be longer than that.
Sinclair sells this <span style="color: #FF0000">$6 item</span> that lets you measure your own chamber to see what is the true max length for your gun. Then trim several thou shorter than that. </div></div>
That product measures from the breech face to the end of the chamber neck... and so carries two out of control independent variables... 1) the headspace of the gun, 2) the case shoulder push back.
The serious problem may be masked of a cartridge that chambers, but when pushed forward by the firing pin, then pinches the bullet, causing a pressure spike.
From my previous post:
<span style="font-style: italic">..the distance from the shoulder to the mouth of the case is longer than from the shoulder to the mouth of the chamber</span>.
This trimmer trims relative to the shoulder:
http://www.accurateshooter.com/gear-reviews/worlds-finest-trimmer-power-case-trimmer/
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: OldTex</div><div class="ubbcode-body">Different guns have a different amount of space cut into the chamber in terms of case (neck) length. In other words, what might be too long for one gun will be fine for another. The SAAMI 'max' length in your reloading manual is intended to make sure the case will fit into any gun safely. The chamber in your gun most likely will be longer than that.
Sinclair sells this <span style="color: #FF0000">$6 item</span> that lets you measure your own chamber to see what is the true max length for your gun. Then trim several thou shorter than that. </div></div>
That product measures from the breech face to the end of the chamber neck... and so carries two out of control independent variables... 1) the headspace of the gun, 2) the case shoulder push back.
The serious problem may be masked of a cartridge that chambers, but when pushed forward by the firing pin, then pinches the bullet, causing a pressure spike.
From my previous post:
<span style="font-style: italic">..the distance from the shoulder to the mouth of the case is longer than from the shoulder to the mouth of the chamber</span>.
This trimmer trims relative to the shoulder:
http://www.accurateshooter.com/gear-reviews/worlds-finest-trimmer-power-case-trimmer/
Re: 5.56mm/.223 Trimming
With my setup it's quicker and easier to just trim every time. I use a separate toolhead on my 650 with a RT1200 and universal depriming die. Tumble the cases just long enough to get the range crap off them (15-20 min) then spread on a large cookie sheet and spray with Dillon spray lube. When dry it's into the case feeder and crank away. Out with the primers and all cases are sized and trimmed. About 1k pieces per hour.
Then into the stainless steel pin media and tumbler for a couple of hours. Out comes like new brass. Since the Dillon sizing die in the trimmer doesn't expand the case neck I just use a Lee Collet die as an expander in Station#1 of my "loading" toolhead. I get nice even, center of the cannelure, crimps on all my finished rounds that function flawlessly in any of my three AR's.
For me, it's just easier to do them all. That way I have no dinged up case mouths, all of the case mouth's are square to the axis of the case, and I don't have to sort out anything but obviously damaged cases.
With my setup it's quicker and easier to just trim every time. I use a separate toolhead on my 650 with a RT1200 and universal depriming die. Tumble the cases just long enough to get the range crap off them (15-20 min) then spread on a large cookie sheet and spray with Dillon spray lube. When dry it's into the case feeder and crank away. Out with the primers and all cases are sized and trimmed. About 1k pieces per hour.
Then into the stainless steel pin media and tumbler for a couple of hours. Out comes like new brass. Since the Dillon sizing die in the trimmer doesn't expand the case neck I just use a Lee Collet die as an expander in Station#1 of my "loading" toolhead. I get nice even, center of the cannelure, crimps on all my finished rounds that function flawlessly in any of my three AR's.
For me, it's just easier to do them all. That way I have no dinged up case mouths, all of the case mouth's are square to the axis of the case, and I don't have to sort out anything but obviously damaged cases.
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