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Satanta
Advanced Member


USA
176 Posts

Posted - 12/29/2017 :  8:34:41 PM  Show Profile Send Satanta a Private Message  Reply with Quote
Sorry everyone. Seems like I'm flooding the site with so many questions.
I tried going back and reading other posts, but could not find what I'm after. I have received most of my reloading stuff. My bible is delayed for some reason. So here I am again.
I got my dial caliper, digital is still coming. So I actually have nothing to compare or back this up with yet.
Just playing before I get set up. I measured my one time spent PPU cases. Did not check all since I have over a hundred. Random grab of seven. All were under 1.280 most at 1.275 some even at 1.272
It might be the caliper, have yet to confirm with another.
All I'm reading is 1.280 is minimum. Now is that meant for sizing?
Or is that meant for overall? Seems like I read somewhere that a case length of 1.265 was acceptable providing head space is good.
Both my carbines are spot on with the minimal head space plus .001
Maybe once I get set up and resize, will they grow in length?
If not? Do you toss them? or just lightly chamfer and go with it?
Not getting ahead of my learning here. No bench, no powder, no primers, no bullets. But my first try at this raised questions.
All 100 plus PPU ran and cycled great. Yet was surprised when I measured the spent case length.
I do know it's better to be short than long. I would never with my carbines even think of a 1.290 sized case. Not worth the risk for me being new at this.
Ha -- think I tossed enough out there for one evening.

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americanboy
Advanced Member



USA
346 Posts

Posted - 12/30/2017 :  07:43:20 AM  Show Profile Send americanboy a Private Message  Reply with Quote
If all your fired cases seem to be measuring shorter than 1.280, I'd say you have an instrument problem, or instrument use problem. I know you're a mechanic, but it's impossible to believe that commercial once-fired cases will be below 1.280. I have never found a commercial case loaded shorter than around 1.284 and most run 1.286 to 1.288. The MINIMUM safe case length is 1.280. Fired cases should be running closer to 1.290.

1.680 is the maximum overall round length from the base to the tip of the projectile. This can vary with the load data and projectile profile, but should not exceed 1.680.

There has to be a standard established for anything and a case-length of 1.290 is the standard established for the carbine. It's a safe standard for millions of carbines. It's impractical to establish a standard for each individual gun. 1.290 is safe for any USGI carbine. However, case-lengths in excess of 1.290 can safely be loaded and fired. The go is 1.290. The no-go is 1.296. The field is 1.300. You can see that it's the condition of the gun that sets it's own standard and this changes over use. If you determine the exact head-space in your gun, you can determine the longest/safest case length. If your gun no-go's at 1.298, you can safely shoot longer cases and save on the brass trimming. YOU HAVE TO KNOW YOUR GUN, but in the meantime...trim it all to 1.290 or slightly less.

DO NOT trim below 1.280. I'd say if you have fired cases 1.290 (or even a little longer) they can be good-to-go without trimming. Don't trim unless you have to and you may not have to every time they are fired.

Edited by - americanboy on 12/30/2017 07:45:53 AM
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daboone
Junior Member



USA
73 Posts

Posted - 12/30/2017 :  07:53:10 AM  Show Profile Send daboone a Private Message  Reply with Quote
Check out ebay for caliper gauge block. They are 1in long rods and come with some micrometers but sold on ebay separately. Like a set of scale weights they will assure confidence in measurements.

With that max of -.008 off of SAMMI I'd not get to excited. After sizing you'll see some lengthening. Many years ago I pick us about 1800 "once fired" M1 Carbine cases and from a guy who had access mil surplus. Like your cases they were all over the place. Most of those exceeded trim length but some didn't. M1 Carbine is the one "straight" walled case that does grow/lengthen after sizing and firing. As I been reloading for 59+ years I have rarely found a new and many once fired case of any caliber that was not already shorter than the "Trim to length". So I'd size 'em, load 'em and have FUN. Other opinions may vary .......
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americanboy
Advanced Member



USA
346 Posts

Posted - 12/30/2017 :  08:55:15 AM  Show Profile Send americanboy a Private Message  Reply with Quote
daboone just brought something to my mind that I had completely overlooked. I was considering your measurement to be after sizing...and that was not accurate on my part. Prior to sizing, fired case lengths can be all over the place and below 1.280. Make your test measurement AFTER sizing and I'm sure you will arrive at an entirely different and more favorable result. My bad!
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Satanta
Advanced Member



USA
176 Posts

Posted - 12/30/2017 :  11:08:06 AM  Show Profile Send Satanta a Private Message  Reply with Quote
Thanks guys as always. Glad to hear and kind of hoped that would be the case before sizing. Found an old link and Tuna said the same. Measure after resizing. Just picked up a nice solid wood desk with two drawers. Nice work top, 4'x 2'4"
Price $0.00 sweet! Now I can get my press mounted and do some case resizing, then measure.
Getting there. Yeah! Thanks again.
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Satanta
Advanced Member



USA
176 Posts

Posted - 12/30/2017 :  4:39:06 PM  Show Profile Send Satanta a Private Message  Reply with Quote
Happy to say all is good. Got set up and began resizing. Did about 75 so far. All are over 1.286 most at 1.290 or above. Saving my longest for set up with the cutter. Ha! gotta have room for error at the start of learning.
I'm enjoying it, but must say it's very time consuming right now. Baby steps with worry, but sure it will come easier. Get the groove going so to speak.
Only frustration I have right now is I need to change the Lee ram 180 degrees. They have the slot on the wrong side for primer disposal. Spits them out on the wrong side and end up in the carpet.
I'm also probably using more lube than necessary. It's the Lee lube and I thin it with a little water, let dry. But I do it with every case. They say every 3 to 5 is all that's needed.
Tuna, if your watching. Run your cleaning process by me once again. Critic acid, dish soap, etc?
Need to order the Bayou Bullets, primers and H110 powder. I will be asking later on the seating of the bullet.
I know the bible will tell me so. But I like the hear from the users also. Concern is crimp. I understand no crimp is necessary if done right from the start with the depth of the expand tool. Over crimping can be dangerous if not correctly done, and if not needed at all.
I was planning to cut my cases at 1.285 but of course want to get life out of them also. Suggestions??
Many thanks again.
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americanboy
Advanced Member



USA
346 Posts

Posted - 12/30/2017 :  5:01:29 PM  Show Profile Send americanboy a Private Message  Reply with Quote
The best reason to trim all your cases to the same length, is that you can set-n-forget your dies and get the same results for each round punched-out. The downer to that is, you may be trimming brass away that could lengthen the case life. You could group your brass and make any necessary adjustments a-group-at-a-time.

Generally, one would only crimp the case enough to bring it back into spec. at the case mouth....remove the bell. The case-mouth rests on the ledge in the bottom of the chamber where it head-spaces. Don't over-crimp a round that head-spaces on the case-mouth.

A good lube: One ounce of lanolin to 6 ounces of alcohol. Toss the brass in a plastic bucket, hit it with a few squirts from a bottle, shake it around, dump them out to dry. This mixed one time will last until you lose the bottle.
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Satanta
Advanced Member



USA
176 Posts

Posted - 12/30/2017 :  5:57:12 PM  Show Profile Send Satanta a Private Message  Reply with Quote
Got you on the length thing and saving brass except for the length desired. I guess I'm asking, and only asking because we all know the bottom line is the gun or guns your shooting with. Do you cut yours at the middle, at 1.285 or say maybe above that? I would feel very comfortable at 1.287 but just not sure.
Sorry to say I am lost on the crimp thing. I get the bell at the bottom of the case. Not good if it's there.
From what I'm reading. Seating the bullet depends on a lot of things and of course I have yet to get there.
The die I have for that will expand the case mouth and load you powder all in the same function. Depending on if you choose the auto powder feeder of the leveled scoop. My question is I think. How deep do you go with the mouth expander to receive the bullet? All the way, or say half? Letting the bullet do the rest of the work, hence an unneeded crimp later? I think heha, that's my question. I hear of people that either over expand, or go to deep. Then find that they can push the bullet in future with their finger pressure.
So they then go back and use a crimping tool to fix. Info per forum reply that I got was, BAD. Don't try to fix a mistake, find out what was done incorrectly to begin with. Carbine 30 should not need a crimp at the bullet if done correctly. Fitted proper with enough expansion at the case end to receive the bullet used is plenty.
Let the bullet self crimp so to speak??
I could be way off base here. But that's why I ask so many questions. I do read and read till I'm blind. But this bit of info stuck with me. Over and under crimps are bad. Once again, I guess it's just getting your feet wet and seeing how you and your dies per adjustment get along.
Thanks again for your info and support.
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daboone
Junior Member



USA
73 Posts

Posted - 12/31/2017 :  07:41:36 AM  Show Profile Send daboone a Private Message  Reply with Quote
Sounds like you'll be using Lee's powder thru expander die. I do too. When You get set up the fun begins learning die adjustment. I have dies from RCBS, Lyman, Redding, Hornady and Lee. Each and every one comes with a set of instruction that will detail die adjustment. Reading them is the easy part. The fun begins when doing the "final" adjustments but isn't difficult. With the powder thru expander type die getting the correct bell or expansion is probably the most time consuming. You just gotta size up maybe 10 cases and adjust that die to get just enough expansion or bell to allow the bullet to sit straight up and not wallow around. The seating dies come in flavors, crimping, taper crimp and non crimping. For the M1 Carbine a taper crimp work best when adjusted to JUST remove the expansion/belling plus a tiny bit more but not cause and inward crimping. As American Boy mentioned this round headspaces off the case mouth.
This may sound complicated but it's not, just time spend with some practice loading in each stage. Actually the most time consuming part, for me, is getting consistent seating depth and concentric alignment.
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americanboy
Advanced Member



USA
346 Posts

Posted - 12/31/2017 :  07:43:49 AM  Show Profile Send americanboy a Private Message  Reply with Quote
A lot of this is trial-n-error and you can adjust the process to suit what you feel comfortable doing. I don't know of any specified expanding depth, you just open the mouth enough to start the bullet, too much and you're over-working the brass. Not enough and you will crunch a case-mouth if the bullet doesn't start. I set the expansion high and test a few passes until I get the expansion opened only enough so the bullet will "stick". Seating the bullet will do the rest. Just about any amount of expansion is going to require a crimp to reform the case-mouth to spec. I was taught by others to just "bump" the crimp die and of course "bump" is a subjective matter. The specification for the diameter of the case mouth for 7.62 x 33 is .336. You may find commercial loads a little less and most of mine wind-up at around .333, but all this relates to just how accurate we can measure. Using good brass and a proper .308 bullet, it's difficult to compress the mouth much smaller than this.

Where you trim is a matter of personal choice and how best to run your equipment. I load one-at-a-time and can make minor adjustments if necessary as I go. With a progressive set-up....the brass must be the same length to achieve repeated results. Most people trim to 1.285-or-so. Some don't trim until the sized length exceeds 1.290.

With a progressive system and metered powder charges, you just have to have faith. Some insist that's the best way to prevent double-charging. I say it's a good way to get double-charges and load all mine individually by hand from a dipper of a known throw-weight with the powder being used.

A word on the Lee powder-thru die...I HATE the way they machined-in the bump that occurs when the case is withdrawn after expansion. I know it's intended to knock the powder off the funnel down into the case, but it can also be a big mess-maker. I don't even use it as a powder-thru die...only for expansion.
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BEYU
Advanced Member



USA
302 Posts

Posted - 12/31/2017 :  4:07:09 PM  Show Profile Send BEYU a Private Message  Reply with Quote
quote:
Originally posted by americanboy
[
With a progressive system and metered powder charges, you just have to have faith. Some insist that's the best way to prevent double-charging. I say it's a good way to get double-charges and load all mine individually by hand from a dipper of a known throw-weight with the powder being used.





I am another one of those who uses the Lee Auto Disc and powder thru die. So far, I've found it pretty accurate but I never trust it. I visually inspect every case after charging to verify: (1) there is powder in the case, and (2) it is not double charged.

It only takes a moment and keeps me feeling confident as to safety.

If I have the slightest doubt, I pour the powder back into the hopper and start again.

BEYU

"Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety."

- Benj. Franklin
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Satanta
Advanced Member



USA
176 Posts

Posted - 12/31/2017 :  4:53:30 PM  Show Profile Send Satanta a Private Message  Reply with Quote
I get you on the worry of the auto powder feed. I have not got there yet, but it does concern me also.
The cats ass would to have the digital scale to measure each case weight after the charge was inserted.
The visual is good once you get the eye for it. Under charge mostly I would think. An over charge or double would have the case running over I would think? Not knowing of course because I have yet to travel there.
My bible still has yet to arrive. I will indeed study it, but too me, their is no better learning from people of trust with the been there, done that. I read all I can get my eye's on. Adjust mental from 1 to 10 on input overall.
Congrats, You all are on the top. Good people, good advice, never boo ya, and ton's of support.
AWESOME!
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Tuna
Moderator



3262 Posts

Posted - 12/31/2017 :  7:33:19 PM  Show Profile Send Tuna a Private Message  Reply with Quote
Just be aware that you only want to expand the case mouth just enough for the bullet to start into the case. Then seat it with the seating stem and not have the dies screwed in so you don't crimp yet. Keep turning the seater in slowly measuring the over all length till you reach the required length. Then back out the seater and start with turning the die into the press with the ram and the case and bullet in the die. Once you feel resistance then turn the die in a little bit more and raise the round back up into the die. Repeat this till the round is crimped properly. Then set the lock ring on the die and the raise up the round and turn the seater into the die till it hits the loaded round and your ready to load. You can almost do the same thing with a factory round but I have found it seems to be a better adjustment using your own bullets and brass. Now to clean my brass I just use a vibrating cleaner and ground corn cob. Cheap to use and biodegradable when it gets dirty. If you have a Harbor Fright in your area they have a vibrating cleaner at a very good price and they work quite well.
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BEYU
Advanced Member



USA
302 Posts

Posted - 12/31/2017 :  10:16:12 PM  Show Profile Send BEYU a Private Message  Reply with Quote
quote:
Originally posted by Satanta

I get you on the worry of the auto powder feed. I have not got there yet, but it does concern me also.
The cats ass would to have the digital scale to measure each case weight after the charge was inserted.
The visual is good once you get the eye for it. Under charge mostly I would think. An over charge or double would have the case running over I would think? Not knowing of course because I have yet to travel there.





I'm sorry I did not say that I always weigh the first 10 rds I reload my mistake.

First put the primed but empty case on your digital scale and then zero the scale. By the way, the scale should be set to measure in gr (grains).

Then put the case back into the turret press and insert it into the die, expanding the case and dropping the charge of powder into the case.

Weigh the charged case on your digital scale to make certain you are getting the correct powder charge.

After I have weighed and checked OAL (Over All Length) on each of the first 10 rds, I then check one in ten from then on. But if I see anything I think is suspicious, I'll back track and recheck them.

To help with that, I also weigh a few of the reloaded rds, (primed case, with powder, and seated bullet) and write that down for future reference.

That way I know what a properly reloaded rd should be both in weight and OAL. If I see anything I don't like, I'll use the kinetic pullet puller (We all really need one of those for our mistakes) and unload the bad reloads and start over.

Visual checks are good, but, by the way, depending on the powder and caliber of round you are reloading, usually you do not fill the case, so running over is not a good way to judge it. As an example, reloading .38 special, using HP-38 powder, a max load for a copper plated 158 gr bullet (3.7 grs) only fills the case less than half way.

.30 carbine using H110 powder (15 grs) for a 110 gr FMJ bullet is a bit more full.




BEYU

"Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety."

- Benj. Franklin
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daboone
Junior Member



USA
73 Posts

Posted - 01/01/2018 :  06:24:49 AM  Show Profile Send daboone a Private Message  Reply with Quote
Visual inspection of the powder level after each dispensing is mandatory on my bench. To ease the neck craning and head bobbing to visualize the powder levels I've added a cheap adjustable mechanic's inspection mirror to my presses. On one press it is epoxied on and the other a pipe clamp keeps it in place. After a few powder dumps you can get an accurate eyeball of the fill level and see if it's high or low. Even then it is important to check on the scale at a frequency that feel right for your trust level of the powder measure your using.
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jimb16
Moderator



USA
3118 Posts

Posted - 01/01/2018 :  11:23:47 AM  Show Profile Send jimb16 a Private Message  Reply with Quote
Americanboy, it is not unusual for new cases to be short. Try checking the length of a brand new box of unfired cases. They are often up to 3 thousandths short. As long as they aren't too long, they get shipped or loaded. Remember, these are tapered cases. As long as the case body is big enough to hold the case from "bottoming out" the round will be safe to shoot and it will stretch. You can tell when a carbine case is worn out if after sizing, the case doesn't have enough tension to hold the bullets snug in the case mouth. When the case reaches that point, it is time to toss it into the scrap bucket.

OGCA Lifer,NRA Life member, son of a 325th GIR Glider Rider
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