Sizing question?

[kalielkslayer]

So I set up my “new to me” Franklin Arsenal case trim and prep center today.

I was striving to trim .223 cases to 1.750. I got it set “about” 1.750. Took me a little while but eventually I could figure out when the cutters quit cutting. I also learned (actually read the instructions) to turn the case to make sure it was even.

Anyways, I measured every single case. Most were between 1.748 and 1.751. I had a few longer. Even a couple as long as 1.755. Those I ran back through the sizing die thinking I had short stroked it. But sizing again didn’t change the OAL. Put them back in the trimmer but nothing?

So what’s an acceptable variance for trimmed cases? These ARE NOT for competition or hunting. Just ammo that will function in a variety of guns.

My thought was the body of the case stretches, and that may not be consistent? And the trimmer sets on the shoulder so a longer case is just a longer case. Even though it’s only .004”, I tossed the longer ones.

What am I doing wrong?

This is new to me, but doesn’t seem like brain surgery.

 

[mrawesome22-250]

SAAMI spec is 1.730" - 1.760" acceptable range for 223Rem.

The only true way of knowing what the maximum case length for your chamber is, is to do a chamber casting.

https://saami.org/technical-information/cartridge-chamber-drawings/

 

[NMexJim]

Mixed head-stamps? That’ll do it. Even brass like Lake City will give you some differences. For whamo-ammo, you’re good. Plus, it’s easy to get your pressure off just a hair.

 

[Wreck-n-Crew]

I have the same.trimmer prep center. Are you using the small plastic collet and the second.from the smallest aluminum bushing? The bushing in the correct orientation?

The only other thing comes to mind might be a defunct shaft/bearing that holds the cutter. Make sure that is not moving back and forth.

Also.call them if none of this helps. Customer service is awsome. They can hlep get you fixed.

 

[kalielkslayer]

Mixed head-stamps? That’ll do it. Even brass like Lake City will give you some differences. For whamo-ammo, you’re good. Plus, it’s easy to get your pressure off just a hair.

All RP brass.

 

[FROGO207]

To me the only real advantage to trim them all the same was if you were going to roll crimp the mouths. Getting them the same length would assure a consistent crimp. Using the Lee FCD that's not necessary. I find my ammo is more accurate without crimping so as long as it is less than max length after sizing I load em up for blasting 223.

 

[kalielkslayer]

I have the same.trimmer prep center. Are you using the small plastic collet and the second.from the smallest aluminum bushing? The bushing in the correct orientation?

The only other thing comes to mind might be a defunct shaft/bearing that holds the cutter. Make sure that is not moving back and forth.

Also.call them if none of this helps. Customer service is awsome. They can hlep get you fixed.

So I shouldn’t have any variation, not even .003?

I got this off of eBay. It was in its original packaging. Even the attachments seemed to have machine oil on them, and in the tiny little zip locks. BUT it seems to me, maybe an optical illusion, but the shafts for the deburring tools seem to wobble? I thought they were but I tightened them up and saw the same thing. Like I said, maybe it’s because I’m sitting to the side.

I’ll remove the attachment and look at the cutter tomorrow.

I have the smallest plastic insert and the collar that fit the tightest on the case, but I’ll verify that tomorrow.

So, to be clear, they should all be exactly the same?

 

[kalielkslayer]

To me the only real advantage to trim them all the same was if you were going to roll crimp the mouths. Getting them the same length would assure a consistent crimp. Using the Lee FCD that's not necessary. I find my ammo is more accurate without crimping so as long as it is less than max length after sizing I load em up for blasting 223.

Initially I was going to use a mild taper crimp and see accurate they shoot. Go from there. I won’t mess with OAL, strive to be right at 2.26.

I have some 69 grain BTHPs I was eventually going to work up for one gun I may play with overall length for accuracy in that gun. But for now, standard length and mild taper crimp.

 

[NMexJim]

Initially I was going to use a mild taper crimp and see accurate they shoot. Go from there. I won’t mess with OAL, strive to be right at 2.26.

I have some 69 grain BTHPs I was eventually going to work up for one gun I may play with overall length for accuracy in that gun. But for now, standard length and mild taper crimp.

IMHO, crimping .223 even a little messes with accuracy, but then you’re not too worried about OAL (example not setting dies with an ogive comparator) so that’ll work fine. When you want to shrink that spread, just do a search on this forum.

 

[FROGO207]

Dont think your dies will provide much of a taper crimp if they are Lee or RCBS. Mine don't. Yes you should try crimp or not as far as accuracy. You may get different results. The only rifle rounds I crimp are used in tubular magazine firearms.

 

[Wreck-n-Crew]

So I shouldn’t have any variation, not even .003?

I got this off of eBay. It was in its original packaging. Even the attachments seemed to have machine oil on them, and in the tiny little zip locks. BUT it seems to me, maybe an optical illusion, but the shafts for the deburring tools seem to wobble? I thought they were but I tightened them up and saw the same thing. Like I said, maybe it’s because I’m sitting to the side.

I’ll remove the attachment and look at the cutter tomorrow.

I have the smallest plastic insert and the collar that fit the tightest on the case, but I’ll verify that tomorrow.

So, to be clear, they should all be exactly the same?

No. You will have variation but not .04"! . Too much of a difference between 1.7151 and 1.750". So much so it looks like a typo rather than real measurements.

Doesnt seem to be a problem with the brass if your full lengrh sizing. That shouler will not be off enough to cause that kind of variation. You can measure 100 pieces of mixed brass that has been full length sized in any one die and not vary by much more than a few thousandths measuring from the cartridge base to shoulder.

In fact that would be a good way to eliminate the brass and sizing operation. Using a hornady case comparator for example and measure the base to shoulder on the cases. Although i doubt that is the issue.

 

[kalielkslayer]

No. You will have variation but not .04"! . Too much of a difference between 1.7151 and 1.750". So much so it looks like a typo rather than real measurements.

Doesnt seem to be a problem with the brass if your full lengrh sizing. That shouler will not be off enough to cause that kind of variation. You can measure 100 pieces of mixed brass that has been full length sized in any one die and not vary by much more than a few thousandths measuring from the cartridge base to shoulder.

In fact that would be a good way to eliminate the brass and sizing operation. Using a hornady case comparator for example and measure the base to shoulder on the cases. Although i doubt that is the issue.

Great catch!!!

It was a typo! 1.748-1.751. And 2 cases out of 107 that were 1.755. Those 2 I resized and trimmed, still 1.755.

Sorry for the confusion!

 

[kalielkslayer]

Dont think your dies will provide much of a taper crimp if they are Lee or RCBS. Mine don't. Yes you should try crimp or not as far as accuracy. You may get different results. The only rifle rounds I crimp are used in tubular magazine firearms.

I bought a Lee .223 taper crimp die for this.

 

[FROGO207]

I get enough neck tension using the expander part of the sizing die. You can always make it smaller with some sand paper and spinning it in a drill. I feel if you taper crimp bullets it also hurts accuracy. Found this with handgun bullets early on so I am really careful about taper crimping especially when using lead bullets in handguns FWIW.

 

[eschafer]

are you measuring each case from cartridge base to shoulder, before and after full length resizing? sounds like it not being a trimming issue, but rather a sizing issue....

 

[film495]

I user a Forster trimmer, and once I'm set up - and I'm not doing super accuracy work, I'll go with anything plus or minus .001 - usually they are right on and the variation is in how the brass is held in the calper. Once in a while they are a hair long, and a few more turns in the trimmer brings them into spec.

The Forster trimmer does not use the shoulder, it is just set to OAL to trim - not sure I would dig the additonal variable of linking the headspace to the OAL, seems like another variable I would not need/want. Maybe I am too basic at this point, but don't see why it would be designed like that.

 

[chamokaneman]

Great catch!!!

It was a typo! 1.748-1.751. And 2 cases out of 107 that were 1.755. Those 2 I resized and trimmed, still 1.755.

Sorry for the confusion!

If your trimmer works off the length from the shoulder it sounds to me like those two cases simply have a little bit longer head to shoulder length than the others. In any case, 1.755 is perfectly acceptable.

 

[kalielkslayer]

If your trimmer works off the length from the shoulder it sounds to me like those two cases simply have a little bit longer head to shoulder length than the others. In any case, 1.755 is perfectly acceptable.

All of them are within specs. But eventually I’m gonna load for accuracy.

I did another batch today. I really concentrated on how much pressure I was putting on the cartridge and slowly spun the case 180 degrees after the cutters were done cutting. Most were 1.748-1.751. Not a big difference but I’m striving for perfection. And it seems like the cutters are slow cutting. From 1.768 to 1.750 takes 20+ seconds?

The deburring attachments don’t seem to be straight, they seem to wobble.

I took everything off and cleaned the cutters, they seem dull. Unfortunately, I didn’t turn it on when I could see the cutters. Tomorrow.

My thought is I’ll order new cutters. But I don’t think that’s the problem.

Sad thing is I couldn’t find one, bought one on eBay. Then, before it was delivered, I saw a new one on the shelf for $20 more.

If new cutters don’t fix my problem, I’ll send it back to Franklin Arsenal to get it fixed, and buy a new one if I can find one.

My first case trimming experience so maybe it’s operator error, but I’m trying to be consistent.

 

[JFrank]

So I set up my “new to me” Franklin Arsenal case trim and prep center today.

I was striving to trim .223 cases to 1.750. I got it set “about” 1.750. Took me a little while but eventually I could figure out when the cutters quit cutting. I also learned (actually read the instructions) to turn the case to make sure it was even.

Anyways, I measured every single case. Most were between 1.748 and 1.751. I had a few longer. Even a couple as long as 1.755. Those I ran back through the sizing die thinking I had short stroked it. But sizing again didn’t change the OAL. Put them back in the trimmer but nothing?

So what’s an acceptable variance for trimmed cases? These ARE NOT for competition or hunting. Just ammo that will function in a variety of guns.

My thought was the body of the case stretches, and that may not be consistent? And the trimmer sets on the shoulder so a longer case is just a longer case. Even though it’s only .004”, I tossed the longer ones.

What am I doing wrong?

This is new to me, but doesn’t seem like brain surgery.

My guess is your brass is not consistent in length from the case shoulder junction to the web, perhaps you have your die set to a longer example or some are once fired and lack consistency also mixed headstamped range brass has no history leaving you to wonder.

 

[kalielkslayer]

It’s once fired, same headstamp. But I measured a bunch of it before I trimmed it, and the OAL varied a few thousands on each side of 1.765.

 

[chamokaneman]

From 1.768 to 1.750 takes 20+ seconds?

I have a hand me down Lyman trimmer I struggled with some too. I ended up with a new carbide cutter head and also replaced some little cams in the universal shell holder that seemed to do the trick for me.

.015-.018 is quite a bit to take in one bite. One thing you might try is to stop a few thousands long. Hit them with the deburring head and then take the last few thousands in another pass. 1.748 to 1.751 is still pretty good though. Much less and your down to slight variations in measurement.

 

[kalielkslayer]

I have a hand me down Lyman trimmer I struggled with some too. I ended up with a new carbide cutter head and also replaced some little cams in the universal shell holder that seemed to do the trick for me.

.015-.018 is quite a bit to take in one bite. One thing you might try is to stop a few thousands long. Hit them with the deburring head and then take the last few thousands in another pass. 1.748 to 1.751 is still pretty good though. Much less and your down to slight variations in measurement.

So that’s what I wanted to hear. .003 isn’t bad.

But I don’t want to take away the advice that supports what I’m doing. But I appreciate your comments.

Unfortunately, when I started this thread, I had a typo on length that was way over .003.

I am replacing my cutters. I grind until I’m sure the cutters aren’t cutting, then I slowly rotate the case 180 degrees. Sometimes I hear/feel the cutter reingage.

And your comment about measuring hit me because I’ve thought about that a lot. I can put the caliper on a case and get different readings. I try to be consistent.

 

[Dale Alan]

Sinclair makes just what you need . Easiest way to know exactly what length to trim to ,

https://www.sinclairintl.com/reload...th Gauges,trim lengths in reloading handbooks.