Process questions...

[Wobbly]

Just like he goes by 0.1 or 0.2gr increments for powder, I'm just wondering what the OAL increments  might be.

With what cartridge ?

I know you're probably referring to 9mm Luger, but I don't want anybody thinking there are any such rules across ALL reloaded cartridges. 9mm and 40S&W are in a completely different world from 45ACP.

[daved20319]

Does OAL really make that much difference to accuracy with handgun cartridges?  Or is it more a pressure management thing?  As most of us do most of our shooting at ranges of 25 yards or less with no rest, I can't see it making a quantifiable difference in accuracy.  And if it is pressure management, then wouldn't it pretty much require a chronograph to make sure you weren't crossing the line into the danger zone?  Not trying to be a jerk, but I'm someone that likes to know the "why" behind the "do's".  Plus, I've only gotten back into hand loading in the last couple of years, my previous "experience" was about 40 years ago, things have changed a bit in that time, and I might have changed a bit myself  .  Later.

Dave

[Wobbly]

Everything we do in reloading is to first control Chamber Pressure. Any other actions are simply to put some icing on the cake.

There is no measurable accuracy gain for pistols by placing the ogive of the bullet XXX distance from the rifling. However, there is great amount of safety added when the bullet's nose isn't buried in the rifling. Picture rolling your bicycle's front wheel right up against a curb... and then trying to start off pedaling by jumping the curb. Nearly impossible. Now picture jumping that same curb with a rolling 'head start' on that same bicycle. That's the difference between burring the bullet in the rifling and having a 0.010" head start.

 

[Pistolet]

I consider small .01-.02

Ok that gives me an idea. I still have a difficult time visualizing such small measurements and it dosen't help that I grew up with the metric system so it helps to pull out a few coins out of my pocket. It comes to somewhere between two dimes and three quarters stacked.

[M1A4ME]

Cartridge over all length.  Some aren't very sensitive (pistols or calibers/cartridges).

Some are.  Both the pistol and the caliber.

I never paid much attention to .45 acp.  Loaded it for 30 years with zero issues.  FMJ, LRN, hollow points.  185 grain to 230 grain.  I had a buddy that loaded those 250 grain Keith SWC intended for .45 Colt revolvers for his 1911.  It ate them up and shot nice groups.

I have had several .45 acp pistols over the years.  Finally got one that once sensitive to cartrige over all length.  That Colt Series 70 needed longer COL cartridges than the other Colts, the ParaOrdnance or SA 1911.  So I loaded them longer.  The other pistols continued to eat them up like there was no difference.  But, my nephews XD .45 won't chamber those longer shells.  Different pistols can be different.

.45 acp is (if loaded by the books) a lower pressure cartridge than 9MM or .40 S&W, so small changes in COL won't make as big a change in pressures due to decreases/increases in internal case volume created when bullet depth changes.

Some CZ pistols are very picky about chambering if the COL isn't "right" for them.  Some are not.

I just ran into something a few weeks back I've never encountered before.  Got a new XD .45 acp and plunk tested some LRN reloads.  "Plunked" no problem.  Good to go, I thought.  Grabbed a box of the on the way to the range one day and when I got there I started to load them in a magazine and could only get 3 or 4 into the magazine before they started hanging up on the front/back of the magazine.  Short enough to plunk, too long to load in the magazine.  Usually you can put rounds in a magazine that are just too long for the chamber.

You want your loads to be safe, reliable, accurate and repeatable.  If they aren't all four, you aren't doing something right.

[IDescribe]

Not trying to be a jerk, but I'm someone that likes to know the "why" behind the "do's". 

NOT AT ALL.  If more people cared about the the why of it, of everything, these threads would go more smoothly. 

Does OAL really make that much difference to accuracy with handgun cartridges?  Or is it more a pressure management thing?  As most of us do most of our shooting at ranges of 25 yards or less with no rest, I can't see it making a quantifiable difference in accuracy.

I can't imagine why two bullets of different weights spinning fast enough to remain gyrostablized will have different inherent accuracy based on barrel twist rate, but that's a truth.  I believe physicists call it magic. 

To answer your question, is it quantifiable?  Yes.  Sometimes, yes.  Is it enough to matter?  Depends on your shooting.  It will stop mattering to me when I stop missing A-zone hits by a 16th of an inch. 

It doesn't matter until it matters.  It will depend on the gun and the bullet.  There were some tests done here before I arrived with the Berry's 124gr RN.  This bullet will chamber cleanly at OALs longer than the magazine will allow -- out to about to about 1.122 or something like that.  Max OAL for the magazine is supposed to be 1.169, so the typical protocol is to load shorter than that, let's say 1.160.   BUT years ago, prior to my arrival, some of the locals here ran tests and determined that the bullet is more accurate loaded shorter -- 1.13/1.14, I believe.  So THAT is an example of where it mattered, and there was additional accuracy to be gained by tuning OAL.  And as opposed to long range rifle, where people like to get the bullet as close to the rifling as possible, in this case, it was shorter.

And if it is pressure management, then wouldn't it pretty much require a chronograph to make sure you weren't crossing the line into the danger zone?

Get a chrono.     They're cheap and helpful.  I am well aware that people load for decades without, but they're so inexpensive now, there's no reason not to add one to the gear-set.

Edited to change incorrect word: rates to weights

[daved20319]

I consider small .01-.02

Ok that gives me an idea. I still have a difficult time visualizing such small measurements and it dosen't help that I grew up with the metric system so it helps to pull out a few coins out of my pocket. It comes to somewhere between two dimes and three quarters stacked.

Something is off in your measurements.  A dime is just over .05", a quarter is about .064", and a nickel is .072".  If you're going to reload, you really need a decent set of calipers, a good (enough) digital set can be purchased for well under $50, and will have the added advantage of being able to toggle back and forth between metric and Imperial measurements.  For less, you can get dial calipers in metal or even plastic, but they're generally only one measurement system, and generally only read to two decimal places, i.e. 0.00, where my digital set reads to 0.0005.  Later.

Dave

[daved20319]

Not trying to be a jerk, but I'm someone that likes to know the "why" behind the "do's". 

NOT AT ALL.  If more people cared about the the why of it, of everything, these threads would go more smoothly. 

Does OAL really make that much difference to accuracy with handgun cartridges?  Or is it more a pressure management thing?  As most of us do most of our shooting at ranges of 25 yards or less with no rest, I can't see it making a quantifiable difference in accuracy.

I can't imagine why two bullets of different rates spinning fast enough to remain gyrostablized will have different inherent accuracy based on twist rate, but that's a truth.  I believe physicists call it magic. 

To answer your question, is it quantifiable?  Yes.  Sometimes, yes.  Is it enough to matter?  Depends on your shooting.  It will stop mattering to me when I stop missing A-zone hits by a 16th of an inch. 

It doesn't matter until it matters.  It will depend on the gun and the bullet.  There were some tests done here before I arrived with the Berry's 124gr RN.  This bullet will chamber cleanly at OALs longer than the magazine will allow -- out to about to about 1.122 or something like that.  Max OAL for the magazine is supposed to be 1.169, so the typical protocol is to load shorter than that, let's say 1.160.   BUT years ago, prior to my arrival, some of the locals here ran tests and determined that the bullet is more accurate loaded shorter -- 1.13/1.14, I believe.  So THAT is an example of where it mattered, and there was additional accuracy to be gained by tuning OAL.  And as opposed to long range rifle, where people like to get the bullet as close to the rifling as possible, in this case, it was shorter.

And if it is pressure management, then wouldn't it pretty much require a chronograph to make sure you weren't crossing the line into the danger zone?

Get a chrono.     They're cheap and helpful.  I am well aware that people load for decades without, but they're so inexpensive now, there's no reason not to add one to the gear-set.

Good answers, and BTW, the physicists call it f... magic, gotta get those technical terms right  .  I do have a chronograph, purchased over a year ago and still never used, long story.  But I've owned a couple others previously that saw lots of use, so am very familiar with using them.  Although I will say, it's a lot easier uing them with air guns than firearms  .

My plan is to work up the most accurate load with no pressure signs, then check velocity to verify nothing is weird, i.e. well below max charge, but velocity 200 FPS above book value.  Of course, velocity is less critical for target loads, but will become more important with hollow points, I have a small batch of Gold Dot test loads waiting for my next range trip.  Gonna be a long day when it happens  !  Later.

Dave

[Pistolet]

I consider small .01-.02

Ok that gives me an idea. I still have a difficult time visualizing such small measurements and it dosen't help that I grew up with the metric system so it helps to pull out a few coins out of my pocket. It comes to somewhere between two dimes and three quarters stacked.

Something is off in your measurements.  A dime is just over .05", a quarter is about .064", and a nickel is .072".  If you're going to reload, you really need a decent set of calipers, a good (enough) digital set can be purchased for well under $50, and will have the added advantage of being able to toggle back and forth between metric and Imperial measurements.  For less, you can get dial calipers in metal or even plastic, but they're generally only one measurement system, and generally only read to two decimal places, i.e. 0.00, where my digital set reads to 0.0005.  Later.

Dave

You are right. Wikipedia says one dime=.053 so two dimes = .106  Not .0106 like I was thinking Numbers were never my thing.

I consider small .01-.02

So wow! that's really small!

[eastman]

I consider small .01-.02

So wow! that's really small!

0.25 - 0.5 mm

[IDescribe]

Good answers...

Except that I wrote "rates" when I meant "weights" -- stupid brain.

My plan is to work up the most accurate load with no pressure signs,

This is one of those things that works in rifle loading that is unreliable in pistol loading, and it's more involved in rifle loading than people describe on the internet when they talk about reading pressure signs -- you really need to know how particular components respond to pressure in a particular rifle.

In pistol, you do not want to rely on it at all.  Don't get me wrong -- IF you see pressure signs in pistol, you want to stop, but in pistol, pressure signs don't let you know you are approaching the danger zone.  They let you know you are already well into the danger zone.  This is because even slow burning pistol powders are super fast compared to rifle powders. 

All you need to do to know that reading pressure signs is unreliable in pistols is ask yourself this question:

When used in .38 Special with a max standard pressure of 17,00PSI vs 9mm Luger with a max standard pressure of 35,000 PSI, how does a small pistol primer know to start showing pressure signs at dramatically different pressures? 

The answer: it doesn't. 

The reason it works with rifle is that the powders burn so slow that there is a meaningful progression in pressure signs from one charge weight to the next.  You can watch the pressure signs develop.  In pistol, the progression from no pressure signs to kaboom may be a tenth or two of a grain, or none at all.

[Wobbly]

All you need to do to know that reading pressure signs is unreliable in pistols is ask yourself this question:

When used in .38 Special with a max standard pressure of 17,00PSI vs 9mm Luger with a max standard pressure of 35,000 PSI, how does a small pistol primer know to start showing pressure signs at dramatically different pressures? 

The answer: it doesn't. 

Wish I could say smart stuff like that. Wowsers, that has to be the best mental image and most clear explanation ever. Kudos, sir !

 

[daved20319]

Good answers...

Except that I wrote "rates" when I meant "weights" -- stupid brain.

My plan is to work up the most accurate load with no pressure signs,

This is one of those things that works in rifle loading that is unreliable in pistol loading, and it's more involved in rifle loading than people describe on the internet when they talk about reading pressure signs -- you really need to know how particular components respond to pressure in a particular rifle.

In pistol, you do not want to rely on it at all.  Don't get me wrong -- IF you see pressure signs in pistol, you want to stop, but in pistol, pressure signs don't let you know you are approaching the danger zone.  They let you know you are already well into the danger zone.  This is because even slow burning pistol powders are super fast compared to rifle powders. 

All you need to do to know that reading pressure signs is unreliable in pistols is ask yourself this question:

When used in .38 Special with a max standard pressure of 17,00PSI vs 9mm Luger with a max standard pressure of 35,000 PSI, how does a small pistol primer know to start showing pressure signs at dramatically different pressures? 

The answer: it doesn't. 

The reason it works with rifle is that the powders burn so slow that there is a meaningful progression in pressure signs from one charge weight to the next.  You can watch the pressure signs develop.  In pistol, the progression from no pressure signs to kaboom may be a tenth or two of a grain, or none at all.

Okay, that makes a lot of sense, especially if you've ever looked at a powder burn rate chart.  But it begs the question, if it's so unreliable, how have so many reloaders loaded so many rounds without a chronograph, and with never a kaboom?  And to take it even a step farther, I've seen many posts by (allegedly) long time reloaders claiming chronos are totally unnecessary.  Needless to say, even at my relatively inexperienced level, that sort of comment pretty much disqualifies anything else they have to say  .  I, like most I assume, am very careful to stick with published load data, is that the answer, the the ones publishing that data are being very conservative, thus essentially protecting us from ourselves?

And on a related subject, why don't the manufacturers give more data on bullets?  On all that I've seen, the only info is style, weight, and diameter.  Just by adding two more dimensions, OAL and bearing surface length, you could actually compare one bullet to another without actually having to have both in hand.  I ran into a situation with the Lyman manual and cast lead bullets in .45 ACP.  Same weight, style, and alloy, but radically different charges for two different bullets, and no way of knowing which was actually comparable to the bullet I was using, other than a tiny picture.  I ended up using the (wrong!) heavier load, no damage, but it was obviously too hot for the purpose.  Still have half of what I loaded set aside for chrono testing, just for my own curiosity and future edification.  Later.

Dave

[M1A4ME]

If you use the correct components (especially the correct powder) and you follow the reloading manuals' recommended loads/powder charges and cartridge overall length recommendations and your fire arm is in good condition and you don't try to shoot it with mud, wasp nest, bullet from a dud round in the barrel, there's not much reason for a kaboom.

On another forum, the last few days, some guy is complaining about how he keeps getting "mini-kabooms" in his Glock.  Had 7 or 8 of them in the last few months.  When he finally got around to listing the powder and powder charge everyone was trying to tell him he was well above the max. loads in the reloading manuals and he just wanted to ignore that and keep on going with "why am I getting mini-kabooms."

I haven't clicked on that thread in several days.  Some people are beyond help.  Trying to help them could get you into trouble when he fails to understand what you are telling him, goes further down a rabbit hole in the wrong direction and then blames your "bad advice" for his damage/injuries.

Have any old reloading manuals?  Have any new reloading manuals?  If you do, compare some of the loads.  The reloading books put out by the powder and bullet makers are recommending lighter powder weights/charges fairly often as they update their recommended reloading data.

And, you can, very, very seldom, get hold of a bad/weak piece of brass.  I did.  Once in 40 years of loading and thousands upon thousands of reloaded cartridges.  The CZ85 must be built like a tank, it suffered no damage and the 9MM case came out of the pistol in two pieces.  A rim/base and the rest of the case walls from the base up to the case mouth.

People get distracted while reloading (never a good thing).  I have some distractions while reloading.  The phone rings or the dogs start barking and I need to see what they are barking at - and I stop reloading, deal with the distractions and then go back to reloading. Don't get distracted.  You can seat a primer upside down (dud round, missed deer, etc.)  You could double charge a case with a fast burning pistol powder (KABOOM! in most cases).  You could use the wrong powder (KABOOM! if it's a pistol powder placed in a rifle case.)

Reloading can be fun.  Reloading can be rewarding.  Reloading can supply the most accurate ammo you'll ever fire through your guns.  If you screw up, reloading can damage your gun and you.  Be safe.  Don't get distracted.  Keep a logbook.  Read more than one manual (not just the load charts but the why's, how's, do's/don'ts, etc.)  Ask questions (here is a good place, lot of guys here have a lot of years of reloading under their belts (and through their guns).

[Wobbly]

Okay, that makes a lot of sense, especially if you've ever looked at a powder burn rate chart.  But it begs the question, if it's so unreliable, how have so many reloaders loaded so many rounds without a chronograph, and with never a kaboom?  And to take it even a step farther, I've seen many posts by (allegedly) long time reloaders claiming chronos are totally unnecessary. 

Dave -
You simply have not through this all the way through, my friend.

? What is the most popular pistol sold ?
Glock owns the greatest percentage of the US pistol market. How does the Glock chamber differ from the CZ ? The Glock pistol gives VERY generous clearances on every aspect of the cartridge interface. That means that Glock owners never, ever need to reduce their OAL to get a cartridge to fit their chambers.



? When do you need a chrono ?
You only need a chrono when you are forced to reduce your cartridge OAL due to bullet-to-rifling interference. In ALL cases, it's the gun's barrel that determines the Max OAL. So if your barrel never tells you to reduce your OAL, then you won't ever need a chrono.

I've seen many posts by (allegedly) long time reloaders claiming chronos are totally unnecessary. 

This is a TRUE statement.... for about 60% of US pistol owners. Unfortunately you don't fall in that 60%. 

? Why is the Glock chamber so generously proportioned ?
Because Glock's "claim to fame" is the pistol is utterly reliable and fires every time. Even if you retrieve a mag from a mud puddle in the middle of a fire fight, the mag will lock into the gun and all rounds will fire. Glock markets their gun mainly to police agencies. In law enforcement it is much more important that the shooter be able to return fire, than it is that he/she actually hit something. Glocks #1 standing in the US market is totally built on RELIABILITY. At one time they even had a video of the gun being fired under water !! So the word "accuracy" never enters into the lexicon of the Glock owner, without the words "Lone Wolf" entering too.

So 'yes', any round will fit in the Glock chamber and fire. So 60% of the pistol owners in the US simply follow the load recipe verbatim and their ammo works just fine. Why then would they need a chrono ?


? Hint: If you'll focus your internet reading on CZ and Springfield XD/XM series guns, and away from generic, highly generalized reloading forums, you'll be a lot better off.

Hope this helps. 


PS. Here's some backup information in support of my assertion.