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Discussion Starter #1
The longer the cartridge, the more it is accurate ? Loading 45 acp and looking at load data has me wondering .
Same powder same bullet weight differnt COAL and I know it's not wise to chase COAL but seems like a longer COAL has more potential ?
Best/picker
 

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There is a point longer OAL will give negative results, same could be said about going extreme in the opposite direction as well.

Not even a general rule as to how far off the lands bullets like to be. Some like to be touching enough for the bulled to be pulled out of the case of ejected without firing while others, like 400's example can move more than a 1/2" before hitting rifling.
 

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Er, well, sort of and sometimes...

In the plunk test diagram that is frequently posted the "most accurate with lead bullets" shows the cartridge base flush with the hood of a 1911 style barrel but that is a specific situation and may not be true with all barrels. In that situation, the shoulder of the lead bullet is what the cartridge is head spacing on as we don't have "case stretchers" to achieve head spacing on the case mouth which is what self loading pistols are typically designed to do.

The same applies to rifles. In general rifle cartridges are loaded so that there is some bullet jump from the case to the rifling but there are some barrels that respond well to a shorter bullet jump and carried to the extreme there is a technique for bolt action rifles called "soft seating" where neck tension is left somewhat loose and COL is actually established by the bolt closing and the bullet being set back into the case somewhat by that action. Soft seating is not a technique to be applied in self loading, lever action guns or revolvers! It is only to be applied in bolt action firearms and it is best left to the many hundreds of yards competitive bench rest guys who are trying to wring another 1/8 or 1/16 MOA out of a custom made, bolt action target rifle. For us mere mortals, well, we just can't benefit from it.
 

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Discussion Starter #6
Just something I read, use your barrel to determine Coal and use the longest COAL your magazines/gun will function with.
I'm using 1.265 now and will chrono some tomorrow, I think I am long and I think I am short on powder (4.2 grns. ) Red Dot but some where between COAL and powder weight is my sweet spot, going slow I plan on reducing the coal and increasing the powder charge ?
Best /picker
Ps incidentally I shot some of this this evening and seemed accurate out to 100 yards.
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Just something I read, use your barrel to determine Coal and use the longest COAL your magazines/gun will function with.
This is generally true as long as you don't get into bizarre dimensions which bring on different issues such as insufficient neck tension. The chamber dimensions in properly manufactured pistols are to a great extent self limiting and prevent real problems. The same goes for revolvers and bullets designed to be used in them. In bolt action rifles, this is also usually true but pumps, autoloaders and anything which feeds with a tubular magazine are a different situation due to the possibility of bullet setback.

Loading as long as possible creates the maximum possible useable powder space in the loaded round. That said, rounds such as .45 ACP operate at low pressures and "traditional" signs of excess pressure will not be visible until you are way past SAAMI maximum allowable specifications. As always, approach maximum loads with caution. The extra useable case capacity gives you a LITTLE extra room to work with the emphasis on LITTLE. A chronograph is your friend when working at the upper edge.

Bruce
 

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Perhaps a misunderstanding of the 'rule of thumb'.

... use the longest COAL your magazines/gun will function with.
FUNCTION is the operant word. Rule of thumb to get a 1911 to feed reliably without jamming. But sometimes a shorter COAL feeds better with certain bullets in some guns. For reliable feeding, you gotta test it in your gun to find the best OAL.

Has little or nothing to do with accuracy.

Although (as mentioned above) very often going to extreme either way will interfere with the gun's ability to do its job, and that makes everything (including accuracy) suffer.
 

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Discussion Starter #9 (Edited)
This is all good advice men and we all know how to use printed data to reload, I guess what I'm after is the technique to enable me to tweak a round for a specific pistol that will produce more accuracy.
And it would appear the variables are COAL/ Powder/ and to a lesser extent primers and crimp, that's what I have to work with, so going slow and chrono reduce COAL which should increase pressure ? Or slowly add powder which should produce the same result, increased pressure ?
And I'm talking specifically about one gun a 1911 45 acp with Red Dot and 200 Grn. SWC.
Yes I know there are better powders for the 45acp, but the ways and means to establish the technique is what I'm after.
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Just something I read, use your barrel to determine Coal and use the longest COAL your magazines/gun will function with.
That is fine if you only have one of something or load different ammunition, in the same caliber, for each individual firearm.

Never really messed with OAL in pistols for accuracy unless they were single shot, like the Contenders and XP-100 but they are a different animal than the 1911 all together.

Are you sorting your brass by not only head stamp but by weight as well? What are you trimming the cases to? What kind of optic do you have on the pistol? Some other things that could have as much or more influence on 100 yd accuracy out of a 1911.

What is your test sample size/procedure to actually see what difference your changes are making?
 

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Discussion Starter #12 (Edited)
I should have made myself clear not looking for Rifle type accuracy as you know I shoot steel, but what I want to do is shoot paper until I am satisfied I got the best load for that hand gun.
And I realize printed data will get me there, I also realize store bought ammo will too, so why reload right ?
I know some of you folks have YOUR way of working up a load, just fishing for ideas.
When I stretch that 1911 out to a hundred yds. Open sights and do my part I expect to hit what I'm shooting at, maybe printed data is all I need ?
There is no doubt I'm the biggest varible when it comes to accuracy, I just bought a Wilson and I know it shoots a lot more accurate than I can, anyway thanks for your input.
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It may just be the way you worded your post but always remember to make ONE change at a time when developing loads. When you change two of the variables at one step you'll never know which change made the most impact.

If you are going to shorten your OAL don't mess with the charge. If you're close to maximum charge it is wise to reduce it before you shorten the OAL (which in itself will increase pressure).

In my .45acp loads OAL has far more to do with function than it does accuracy.


Just my $0.02,
Grumpy
 

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That is what I was getting at, what is the definition of accuracy in this case and how repeatable are the results so we can reasonably assume they are cause by the changes we make vs you.

At 100 yds does "long" ammunition with perfect matched brass shoot five different five shot groups into 1" and mixed brass "regular" length ammo shot 5, 5 shot groups into 3"?

Or are we talking about "I seem to hit the plate more with "X" ammo? You really need to test to make sure you are not getting what I call "the header effect".

It comes from all the hard work to put after market headers on an engine and thinking the extra noise and the work automatically makes the care faster regardless of results.
 

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Discussion Starter #15
It may just be the way you worded your post but always remember to make ONE change at a time when developing loads. When you change two of the variables at one step you'll never know which change made the most impact.

If you are going to shorten your OAL don't mess with the charge. If your close to maximum charge it is wise to reduce it before you shorten the OAL (which in itself will increase pressure).

In my .45acp loads OAL has far more to do with function than it does accuracy.


Just my $0.02,
Grumpy
Thanks Grumpy, I have heard that many times COAL has more to do with how a gun functions than accuracy, and yes one varible at a time.
Looks like working the charge up slowly and paper is the plan.
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Discussion Starter #16
That is what I was getting at, what is the definition of accuracy in this case and how repeatable are the results so we can reasonably assume they are cause by the changes we make vs you.

At 100 yds does "long" ammunition with perfect matched brass shoot five different five shot groups into 1" and mixed brass "regular" length ammo shot 5, 5 shot groups into 3"?

Or are we talking about "I seem to hit the plate more with "X" ammo? You really need to test to make sure you are not getting what I call "the header effect".

It comes from all the hard work to put after market headers on an engine and thinking the extra noise and the work automatically makes the care faster regardless of results.
Good points all of them, thinking about this I believe working the charge up slowly to no more than 900 fps and comparing charges on paper is the plan. I agree sometimes you need to call good Good.
Thanks again Best/picker
 

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Thanks Grumpy, I have heard that many times COAL has more to do with how a gun functions than accuracy, and yes one varible at a time.
Looks like working the charge up slowly and paper is the plan.
Best/picker
I have always sought the load giving the best accuracy from any particular pistol that I own. In the beginning I varied OAL in addition to other parameters. My experimentation has satisfied me that OAL plays almost no part in accuracy. Proper feeding & functioning, yes, but accuracy, no.

My testing for the most accurate load is to first establish the OAL for the particular bullet I'm testing. Then select a powder to test. Start with a low charge and work your way up in selected increments. I use 0.2 grains until I've bracketed the "sweet spot" and then refine it in 0.1 grain increments.

I've also formed the opinion that crimp can play a small part in a load's accuracy. Not very significant in a 45acp 1911, but measurable in a magnum revolver load.
 

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Discussion Starter #19
I have always sought the load giving the best accuracy from any particular pistol that I own. In the beginning I varied OAL in addition to other parameters. My experimentation has satisfied me that OAL plays almost no part in accuracy. Proper feeding & functioning, yes, but accuracy, no.

My testing for the most accurate load is to first establish the OAL for the particular bullet I'm testing. Then select a powder to test. Start with a low charge and work your way up in selected increments. I use 0.2 grains until I've bracketed the "sweet spot" and then refine it in 0.1 grain increments.

I've also formed the opinion that crimp can play a small part in a load's accuracy. Not very significant in a 45acp 1911, but measurable in a magnum revolver load.
This ^^^^^^ technique is what I was after...............Thanks man, I appreciate you.
Best/picker
 

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In my experience, a cast lead .45 Auto bullet that just touches the lede/rifling will be most accurate. A jacketed bullet just off the lede/rifling will be most accurate. For rifles, I'll bet there are few top-notch long-distance shooters who don't use the longest COL they can.
With revolvers, in general, a wadcutter that is loaded so ⅛-¼" of the wadcutter is in the throat of the cylinder is often more accurate than the flush-seated rounds the reloader makes; however, it is VERY hard for a reloader to come close to the accuracy of the factory-loaded flush-seated wadcutters (not due to flush-seating, but the factories have worked out other variables).
 
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