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Discussion Starter #1
I've done a lot of reading on this, here in the forums and in books, etc. But I can't find much info on a particular part of the COAL issue.

I know that making the COAL too short means less volume in the cartridge. This means higher pressures. This is especially true of smaller cartridges.

I know that making the COAL too long can mean that the bullet is too close to the rifling and it doesn't get enough "jump". This can also lead to a spike in pressures.

The COAL is part of the load data I'm using. I'm loading 9mm Luger with Winchester Super Field (WSF) powder and 115gr FMJ bullets. I got my load data directly from the Hodgdon/Winchester powder site. That data gives a COL (CAOAL) of 1.169"

So I've set my Lee Pro 1000 to achieve that overall length of 1.169"

I have not done enough reloading to start tinkering with the load data. I don't have a chrono to test them, either. I just want to save money by reloading my range ammo. But I don't want any problems from that, either.

The problem is: My loads are varying from that overall length by anywhere from .001" to .004" or so. And I can't find anywhere that tells me if that much variation is OK.

So the question really is: How much variation from the published C.O.L., or COAL, is acceptable???
 

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I've done a lot of reading on this, here in the forums and in books, etc. But I can't find much info on a particular part of the COAL issue.



I know that making the COAL too short means less volume in the cartridge. This means higher pressures. This is especially true of smaller cartridges.



I know that making the COAL too long can mean that the bullet is too close to the rifling and it doesn't get enough "jump". This can also lead to a spike in pressures.



The COAL is part of the load data I'm using. I'm loading 9mm Luger with Winchester Super Field (WSF) powder and 115gr FMJ bullets. I got my load data directly from the Hodgdon/Winchester powder site. That data gives a COL (CAOAL) of 1.169"



So I've set my Lee Pro 1000 to achieve that overall length of 1.169"



I have not done enough reloading to start tinkering with the load data. I don't have a chrono to test them, either. I just want to save money by reloading my range ammo. But I don't want any problems from that, either.



The problem is: My loads are varying from that overall length by anywhere from .001" to .004" or so. And I can't find anywhere that tells me if that much variation is OK.



So the question really is: How much variation from the published C.O.L., or COAL, is acceptable???


No data to back my thoughts up, but this is what I do.
I would suggest you make 10 to 20 rounds and get a good average, you should be able to do within .005" and be ok as long as your not pushing the max load.
I always inspect my shot brass for problems and chrono my made ammo.
I check OAL every 200 rounds.
 

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Discussion Starter #3
Update: I fired 30 of my first attempts. They had a range in COAL from 1.168" up to 1.175 or so.

They all fired fine and the brass shows no bulging or other signs of "distress." Looks like I'm OK with that small amount of variation.
 

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Discussion Starter #5
OK -- I'm back with another question about overall length.

Yesterday I tried to fire four rounds I had loaded using some new bullets I got.

They are Remington 115 gr FMJ but they have a slightly different shape than the Hornady I had previously used.

I only loaded a few because, using the same COL data as the Hornady, these Remingtons almost fall out of the casing by themselves!

3 of the 4 fired great and felt very "soft". But one of them would not chamber properly into the gun.

I re-measured this round and it's 1.175"

That's when I realized I was using my G26 with the Lone Wolf barrel.

When I got home I got curious about something. I tried chambering the round in two other Glocks. It chambered fine.

SO --

I emailed Remington asking if they have load data for this bullet.

How do others handle variations in bullet shape that affect COL???
 

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"That's when I realized I was using my G26 with the Lone Wolf barrel."

These are the magical words when shooting reloads in any Glock. LW chambers are short and tight and they market these as being match grade and to be used in shooting any factory ammo. Well, news flash, the reason that most LW barrels are bought is to shoot reloads and mainly lead reloads, Simple.

LW will "ream" out your chamber for another $30-40 including shipping to fix their problem at your expense. I had two LW barrels that were atrocious in their chamber dimensions and enough of those customers were also complaining that LW agreed to open the chamber up for free. I don't think they do that anymore. I sent my two barrels in to get "fixed" and they still would not chamber my reloads that other handguns would run all day with. My solution was to buy KKM barrels as I had thousands of cast bullets. I would shoot my stock Glock barrel and see how it works even when shooting lead reloads. Some Glock barrels will lead up and others will not. Also a lot depends, if your are shooting lead, on the hardness and size of the bullets and the powders that you are using.

Your OAL question is kind of one that you figure out what length you need to get them to have them chamber in a particular handgun. I've gone shorter than factory but still within SAAMI specs and it's worked MOST of the time. Right now I am experimenting with going on the longer side OAL but still with SAAMI to see if it helps with an occasional FTF.

The design of the bullet you are using can have a big impact on the feeding as you know. The round nose stuff usually with always feed, but it's the flat nose and HP that can create problems. Throw in some semi wadcutters and now the project of proper feeding can become more complicated. Stick with the round stuff to solve most of the problems but again the answer is trial and error for the handgun that you are working on. Good luck in your efforts.
 

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I have 6 LW barrels and reload RN and HP's in 9mm and 10mm and have not had any feeding problems. I do polish the feed ramps on the barrels. I have used FMJ, Berrys and hard cast lead. I also use a Lee factory crimp dies in my Dillon, I don't know if that really does anything in helping to feed the ammo into the barrels.
 
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