9x19 case trim question

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ccjcc81

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I recently posted a thread about taper crimping, and got some great advice from a lot of people about case trimming. %95 of the replies advise not to trim. A couple of other people replied that they like to trim to keep each round as close to the last as possible. One responder actually scared the heck out of me with a horror story involving disfigurement due to trim neglect. After reviewing all of the replies, plus some very, very lengthy googling and searching on other forums, I’m sad to say that I still don’t know what I want to do.

Please have patience with me. I understand that many of you have already answered my question once, and I hate to burden you again over the same issue. If I have offended you in any way with my pestilence, please read no further. If you’ve got the time, I’ve got a couple more questions for both camps.

First, the NO-TRIM’S (by no means a reference to your love-life, :neener: hahaha!) Many of the responses say to seat the bullet according to COL, then crimp to relieve the expanded bell of the shortest case. Does that mean that I have to dig through 1000 cases to find the shortest one?! Please advise.

For the DO-TRIMS: Do you trim your 9mm brass? Do you trim it all, or just some? Where do you draw the line? I’d like to throw some numbers at you and see what you think. My 9mm die set is still in the mail, but to get an idea of the brass I’m working with, I measured some samples of the brass pre-resizing. According to many of the posts I have read, re-sizing will actually shorten the brass more. I have about 1000 9mm cases. Of those, roughly 500 are PPU, 250 are Remington, and 250 are Winchester. I took 20 cases from each and the average lengths of each are as follows: PPU 0.749”, R-P 0.745”, Win 0.742”. These numbers are well below the minimum trim to length in my reloading manual. The shortest one I’ve found so far is 0.738”, which is 0.013 below my manual’s trim to length. That’s before resizing. So will that case even work? I have done endless forum searching for “what is the minimum case length for 9mm,” and the only answer I can find is “Don’t worry about it, load it and shoot it.” Can anyone tell me what the minimum safe case length is? And if I want to make all of my rounds as consistent as possible, will I have to trim them ALL to the length of the shortest case, even though it is shorter than the trim to length in my manual?

Thanks again very much guys.
 
One responder actually scared the heck out of me with a horror story involving disfigurement due to trim neglect.
BS, something else besides not trimming.

Trim them if you want. I don't.
 
You're right Walkalong, I should be completely honest, it was something else. I think it involved a hammer. It did somehow stem from the trim issue, but it did have a profound effect on this newbie.
 
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I have done endless forum searching for “what is the minimum case length for 9mm,” and the only answer I can find is “Don’t worry about it, load it and shoot it.”
:cool:


Always get case lengths after sizing by the way.
 
re .738/.013 short:

After resizing you may gain a small amount of case length. If not your bullet will be seated .013" less deep than in a perfect case. You will have the same amount of case volume below the bullet (and above the powder). If anything the pressures might drop a very small amount (depending on the powder you're using) because the bullet isn't seated as deep it will release a tiny bit faster.

I would shoot it and not be concerned.

Is there a limit for how short it can be? As long as the bullet is reliably seated,---not teetering at the end of the case and will reliably feed and go into battery--- not really.

I've already shot another 200 9mm unmeasured case reloads since this discussion was started :) (Meant as humor---NOT as a criticism)
 
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CCJCC -
So help us here. Are you taking this ammo to the Nationals, or are you plinking, or exactly what?

Inquiring minds and all that. :D
 
Ha! You called me on that one. I just want to produce the best ammo I can, and I don't want to lose any fingers doing it. It'll be for plinking, but several close friends and family members have already asked me to make them some boolits, and because of this I want to be as well educated about it as possible. Trust me when I say that I am doing my homework, and not just picking the forum's brains about it. (even if it doesn't seem that way) I want to make good shooting, reliable, and attractive ammo that I can be proud of (and stockpile). I want to be able to go shooting more often, too. Initially I'd be satisfied if my ammo has the consistency and reliability of good factory plinking ammo. Who knows where it will go from there?

I will try to be with you all and myself and admit that I am feeling a little bit of newbie vigor. It will probably wear off. No Nationals.
 
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http://www.leverguns.com/articles/taylor/9mm_reloading.htm

The above article details how 9mm case length affects accuracy.

I use FC brass almost exclusively. They range from .750" to .756" (sometimes a bit less, but I use those for plinking) in length after being sized in a Redding carbide die matched to a RCBS shell holder with .010" of material removed from the top. Why? Because the die will not size the case completely when paired with a standard shellholder. An alternative is to get a Lee "U" (undersized) die.

The 9 is a tapered case. The carbide insert in the die is also tapered. The 9mm chamber is also tapered. The more you size, the longer the case gets. The reason people say the case gets shorter after sizing is because most sizing dies do not size the case enough. My Redding die/ shaved shellholder combo actually makes the brass longer. I can take a Win factory virgin case and increase the length by .003" just by running it through my die combo.

I trim my 9mm brass to .750" using a Wilson case trimmer with a custom undersized shellholder. It takes only a few seconds to trim a case, and you don't have to do it again. The benefit is perfectly consistent crimp and headspace. I have reloaded FC 9mm brass in excess of 10 times (usually lose them a that point) without splitting. Trimming, to me, is therefore beneficial.

Say you don't trim: 9mm chambers will acept a .762" long case before you run out of headspace. I have never seen a 9mm case that long. The longest I have seen, and I have been doing this for 17 years, is .756". Therefore, there is no danger in not trimming.

If your cases measure .738" in length, they will prolly not headspace off the end of the chamber. Rather, they will index off the extractor hook. This will result in possible misfires depending on the location of the case within the hook. The case will be able to move forward under firing pin pressure and the .024" of headspace will absorb some of the impact energy. As the above article proves, accuracy will be affected negatively.

What I would do is get a Lee "U" die, resize your cases. See how long they get. Trim to .750", or sort the short ones out and reserve them for plinking.
 
ccjcc81, welcome to THR and the wonderful world of reloading.

Since I had a reloading mentor who was very patient, here goes:

I don't want to lose any fingers doing it.
Use published load data for specific bullet caliber/type, powder, OAL and do not exceed maximum powder charge. Begin with published "start" powder charge weight and work up (load 10 test rounds in gradual powder increments) from there.

I just want to produce the best ammo I can
We all do. For some of us, it is our life-long passion! :D
After 15+ years of reloading, I often realize (and some nice folks kindly point out) how little I know about reloading. :rolleyes:

First of all, I think you are trying to produce "hand loading" quality ammunition from "reloading" process. There is a difference. Hand loading involves using all "new" components, including the case. Some target shooters/hunters hand load because they can hand load better than factory match grade ammunition. Of course, hand loading pistol ammunition with new cases won't require concern over "trimming" case to proper length.

Reloading involves using "used" cases and new components (bullets, powder, primer). Of course, quality of reloaded ammunition is determined by the quality of used case processing and quality of components used.

It'll be for plinking,
This is how I "categorize" different "reloaded" ammunition:

Plinking Load:
- Must reliably cycle slides of all pistols
- Accuracy not too important (3"-5"+ shot group at 15 yards OK)
- Used cases with mixed head stamp (weight variance OK)
- Cases sized on progressive press cycle
- Primer pockets not cleaned
- Cases primed on press
- Lead/Moly/Plated bullets (weight variance OK)
- No powder preference to burn rate (any fast/medium burn rate powder)
- Powder charge-to-charge variance of 0.1-0.3 grain OK
- No primer preference

Match Practice Load:
- Must reliably cycle slides of all pistols
- Accuracy important (Need around 3" shot groups at 15 yards)
- Used cases with mixed head stamp (weight variance OK)
- Cases deprimed and sized separately on a single stage press
- Primer pockets cleaned only if I notice some really dirty ones
- Cases hand primed (Winchester primer preferred, but not essential)
- Lead/Moly/Plated bullets (weight variance 1-3 grains OK)
- Powder preference (medium burn rate powder - W231/HP38/WSF/HS6)
- Powder charge-to-charge variance of 0.1 grain required

Match Load:
- Must reliably cycle slides of all pistols
- Accuracy important (Need around 2" shot groups at 15 yards)
- Used cases with mixed head stamp - Same head stamp preferred (weight variance OK)
- Cases deprimed and sized separately on a single stage press
- All primer pockets checked, but not always cleaned
- Cases hand primed (Winchester primer only)
- Jacketed bullet (bullet-to-bullet variance of 1 grain required)
- Powder preference (medium burn rate powder - W231/HP38/WSF/HS6)
- Powder charge-to-charge variance of 0.1 grain required

Extreme Match Load: (I don't do this, but some shooters do)
- Must reliably cycle slides of all pistols
- Accuracy important (Need around 2" shot groups at 25 yards)
- Once fired case and same head stamp
- Cases sorted by weight and grouped by variance
- Cases deprimed and sized separately on a single stage press
- Perhaps case lengths checked and trimmed
- All primer pockets cleaned
- Flash holes made uniform
- Cases hand primed (primer of choice)
- Jacketed bullet (same bullet-to-bullet weight) - sorted and grouped by variance
- Powder preference
- All powder charges hand weighed/powder trickler

I want to be as well educated about it as possible but several close friends and family members have already asked me to make them some boolits
Start by not calling bullets "boolits" as they are projectiles. Loaded/reloaded rounds are ammunition often referred to as "ammo/bullets"

There are many good reloading manuals you should read cover to cover to "start" educating yourself. You will be simply duplicating published loads for a long time. I have yet to experiment my own loads outside the boundaries of published load data. Many gun/reloading forums provide entertainment/amusement/irritation and often not real education (Of course, you will get some useful information on THR from "some" members) :D As always, follow internet/online/forum recommendations at your own risk!
For me, I prefer to only trust published load data that's been tested/proven.

Those new to reloading, I do not recommend reloading for others due to safety/liability concerns. I am sure the temptation will arise as soon as people find out you are reloading bullets and ask you to reload for them (and offer you money). But you must first determine that your reloads are safe for your firearm(s) and other firearms. Imagine your friends/family members shooting your reloads and experience a squib (reloaded round with no powder and live primer - when primer is struck, bullet is pushed into the barrel but does not leave the barrel). Not realizing what really happened, they perform TAP-RACK-BANG drill - slap the magazine bottom, rack the slide and chamber another round, but instead of bang, they will get a BOOM, possibly with a split barrel and explosion that sends gun parts all over the place. This explosion may cause temporary/permanent physical/emotional injury. How can you ensure that you do not give your friends/family members unsafe reloaded ammunition? You must make that determination and time and experience helps.

I want to make good shooting, reliable, and attractive ammo that I can be proud of (and stockpile).
Absolutely, we all do.

I want to be able to go shooting more often, too.
The whole point of reloading.

Initially I'd be satisfied if my ammo has the consistency and reliability of good factory plinking ammo.
Factory plinking ammo sucks. You will find that your reloads will often outshoot most "cheap" factory ammunition.
Who knows where it will go from there?
And that's the reloading journey and passion. We all hope and wish that the journey there is safe and free from accidents, injuries, lawsuits, etc. ;)
 
918v must be shooting 9MM Benchrest, cause he is certainly taking it to a level most do not. I have no doubt if we used a Ransom Rest and shot our ammo vs his at 100 yards, his would win out. :)

All I need is minute of clay pigeon (stationary of course) at 100 yards.

To address an earlier point, trim length will have pretty much zero affect on pressure. The bullets are loaded to the same depth on all the cases regardless of their length, assuming your set up is OK and seating consistently.
 
Redundancy Can Be A Good Thing

Many of the responses say to seat the bullet according to COL, then crimp to relieve the expanded bell of the shortest case. Does that mean that I have to dig through 1000 cases to find the shortest one?!

I do not and have never trimmed pistol cases, as I stated in your previous thread, and I have never had an issue with crimping, firing or functioning. The travel of the case into the crimp die is not critical, and after adjusting the die to remove the crimp from a round, give it another 1/4 turn & you're set. The guys who do trim are not from Mars, just a bit more OC than us non-trimmers. Doesn't hurt, helping is subjective, but it's personal preference, not a must-do like bottle-neck rifle cases. I have some 45 cases that I picked up at the range at McKellars Lodge at Ft Bragg in 1973 that I still use - not for hot loads, but plinkers - and have never trimmed. I have some 9x19 cases I've had even longer, so it's not just some odd cases. Every now & then I get a split & trash it, but I get them in new cases, too. Stop worrying & start reloading - time's a'wastin'!
 
Thank you for that fantastic post.

First of all, I think you are trying to produce "hand loading" quality ammunition from "reloading" process. This is how I "categorize" different "reloaded" ammunition:

I think your right.

Those new to reloading, I do not recommend reloading for others due to safety/liability concerns.

I know your right. I guess it would be a good idea to reload for a few years before indulging my friends. Thanks for that advice, should have been common sense.

Thanks for the catagories. I will never call you an impatient mentor.
 
To address an earlier point, trim length will have pretty much zero affect on pressure. The bullets are loaded to the same depth on all the cases regardless of their length, assuming your set up is OK and seating consistently.

You're right. Thanks Walkalong.
 
I do not and have never trimmed pistol cases, as I stated in your previous thread, and I have never had an issue with crimping, firing or functioning.

Stop worrying & start reloading - time's a'wastin'!

It sure is a wastin'. Thanks for your responses guys. I appreciate them all. I fear that I have wasted a lot of our time. I'll get my dies and new manuals Wednesday, then powder, primer and bullets I'll get over the course of the next month or so. You guys will see a post from me when I get my first rounds completed and tested.(good news I hope) Thanks for all your feedback.
 
I haven't trimmed 9mm brass since I started. None of it has gotten too long.
bds, "boolit" refers to the saying at castboolits.gunloads.com for a lead cast slug. I use it byself sometimes. Boolit = cast lead, bullet = jacketed. Cast another 120 just an hour ago to kill time. :)
 
I fear that I have wasted a lot of our time.
Not at all. We all started out like you, for some, a long, long time ago. I am sure we all "wished" we had asked questions and taken the time to consider things like what you are doing to avoid the common mistakes reloaders make. Unfortunately, some of us rushed into reloading with overconfidence and not enough of "reading the manual" and made mistakes (some minor and some serious) that broke equipment/body parts. It's always better to be safe than BOOM.

Believe me, we all make mistakes (I for one have). You too will have enough of, "Dang, that was close and I won't do THAT again!" and drive home shaking in your car. :eek::D
You guys will see a post from me when I get my first rounds completed and tested.
It's an addictive hobby that bites very hard. You will have a lot of fun and sense of proud accomplishment when you see a tight shot group from your reloads.

"boolit" refers to the saying at castboolits.gunloads.com for a lead cast slug.
armoredman, yes it is an endearing term I use too for lead bullets (especially if they are cast yourself) among reloaders I know, but some general shooting public is not aware of the bullet casting aspect and may think of the term differently.
 
I thought "boolit" was just a humorous way of say "bullet" in a forum. Learned something new.

Many years ago when I was young I would go to visit my uncle way out in east Texas. He would put me to work casting bullets. I must have cast about 3000 during my visits. At that young age I couldn't call it "fun", but it was interesting. That's something I know I could do, and eventually will when I start loading for .357 and .44
 
From the horse's mouth - http://castboolits.gunloads.com/showthread.php?t=40260

45nut - Cast Boolits Founder/Site Owner

What is a "Boolit"?

Boolits = as God laid it into the soil, grand old Galena, the Silver Stream graciously hand poured into molds for our consumption.

Bullets = Machine made utilizing Full Length Gas Checks as to provide projectiles for the masses.
The "term" boolits is starting to spread, it is also a nice way to differentiate quickly what/which we are discussing.
 
I haven't trimmed any 9x19 brass, loaded 10's of thousands of rounds from mixed source brass. As long as I have sized them enough, they drop into a cartridge headspace gage.
 
I used some pliers to remove a bullet from a win case and the case measured 0.746"!

Incedentally, while I had a load of powder loose on the bench, I looked at it through my microscope. I took some pics. I also threw 2 live rounds in the tumbler with a bunch of .223 brass. I'm going to let one tumble for 1hr and let another tumble for 24hrs and look at the powder in each and post them up in a new post for everyone.
 
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Sneek preview

This is the powder from a live cartridge tumbled for 1 hour. The last 4 pics are of my gloved finger. I rubbed it across about %50 of the surface of the yellow bucket to collect any dust that I couldn't get onto my slide.
 
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