New to reloading. Need some advice

Tengo1

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Dec 7, 2010
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So after saving brass for 10 years I finally dived into the deep end with reloading this past year. It’s been 12 months of slowly gathering parts, I just tonight started my load development for Hornady .308 178 gr ELD’s.

Brass is once fired Federal from factory gold medal match.
Primers are Federal 210M large rifle primers
Bullets are Hornady 178 gr ELD’s
Powder is IMR 4064.

Using Hornady’s reloading manual it shows the range as 35.3 to 41.7 gr

088534C4-5326-47ED-8838-D5DA465F8A6A.jpeg


I started at the minimum and did one round each at .03 increments. From 35.3 gr to 40.2 my OAL was consistent at 2.170.
6D56A60D-87CD-40E1-80A6-F9EC4DE906AA.jpeg

As soon as I jumped to 40.5 I could feel and slightly hear the load compress. I measured it and it bumped my OAL to 2.174
C7E53E3F-0B20-41D9-8022-31B041874E80.jpeg

I loaded one more round at 40.8 gr and could feel and hear the load compress again. Checked the OAL and it had now bumped my OAL to 2.180. So at this point I stopped although Hornady lists max at 41.7.
32DB3453-B242-4F16-A7F7-1C362CD9A0C7.jpeg



Questions:
Is .308 compressed ok?
Obviously I’ll start at the minimum when I fire them, but would you even bother attempting to shoot the 40.5 and 40.8 loads that I know are compressed and bumped my OAL?
Would my brass type, Federal, account for the load compressing almost a full grain before max?
 
"Max" is kind of like that line from Pirates of the Caribbean..."they are more like guidelines rather than rules".
"Max" even in that reloading manual is for THEIR gun, THEIR barrel, THEIR environment, etc. None of that directly translates to absolute terms to all guns.

Even small things can cause pressures to 'become max'... if you use a powder that is heat sensitive, your max load if you are shooting in January can easily be different than your load shot in July. Using the same brass, same bullets, same powder, same gun... the 'max' is a moving target in many instances.

A compressed load is not necessarily a horrible thing, but I think you are getting way ahead of yourself. Some powders are simply a lot more bulky than others. Some brass has a lot less or more capacity than others. New brass can have a lower capacity than once fired brass. There are a ton of factors that can lead to a compressed load. With some variables they can be totally safe, but with others not so much.

However if you are new it's a good idea to stay away from the edges until you get a lot more comfortable.

What your question should be is 'what signs should I look for to detect over pressure?'. You got the right spirit but just the wrong question. The only way to know for sure is to actually shoot, not by just going 100% by the manual. Your max could be a whole lot lower than their max.

In other words don't get ahead of yourself. Just load up a few rounds at each charge weight and shoot them. When you do, after each shot check your brass for pressure signs. If you see pressure signs STOP shooting. And also on that note, save yourself a whole lot of problems by just loading the minimum number of rounds to do this test. You can easily do this with just a few rounds, not 100 rounds.

On that note one guy I know got gung ho and loaded like 10 rounds at each charge weight and had like 100 rounds. He ended up having to pull the bullets out of around half of them. In other words loading up too many rounds, especially in this stage, can cause you a lot more work.

Other people here really like to go to the utter maximum on everything. A lot of the time those same folks have been reloading a long time and know the risks involved. I however don't try to get to max all the time. A lot of the time you can find a really good shooting load well off of the listed maximums.
 
Last edited:
I appreciate the advice. That is the plan. To start shooting the lowest charge first and check for pressure signs as I go up. I just didn’t know if a compressed .308 load was a hard “don’t shoot that” rule of thumb.

I just got a magneospeed V3 so if I find a decent spot in the middle of the range for groups I’m by no means trying to run hot loads in my .308
 
So after saving brass for 10 years I finally dived into the deep end with reloading this past year. It’s been 12 months of slowly gathering parts, I just tonight started my load development for Hornady .308 178 gr ELD’s.

Brass is once fired Federal from factory gold medal match.
Primers are Federal 210M large rifle primers
Bullets are Hornady 178 gr ELD’s
Powder is IMR 4064.

Using Hornady’s reloading manual it shows the range as 35.3 to 41.7 gr
started at the minimum and did one round each at .03 increments. From 35.3 gr to 40.2 my OAL was consistent at 2.170.
View attachment 7818819
As soon as I jumped to 40.5 I could feel and slightly hear the load compress. I measured it and it bumped my OAL to 2.174

I loaded one more round at 40.8 gr and could feel and hear the load compress again. Checked the OAL and it had now bumped my OAL to 2.180. So at this point I stopped although Hornady lists max at 41.7.

Questions:
Is .308 compressed ok?
Obviously I’ll start at the minimum when I fire them, but would you even bother attempting to shoot the 40.5 and 40.8 loads that I know are compressed and bumped my OAL?
Would my brass type, Federal, account for the load compressing almost a full grain before max?
Couple of points to consider. In their manual Hornady lists the OAL for the 178 gr ELD as 2.800". It appears that you are measuring Cartridge Base to Bullet Ogive (CBTO).

What is the Over all Length (OAL) of your bullets, when the CBTO is 2.170"? Would your loads be compressed, if you loaded the bullets at 2.800" Over all Length (OAL)?

I suspect that you are increasing your charge weight in 0.3 grain increments rather than 0.03 grain increments.
 
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Compressed loads aren't necessarily a bad thing in terms of safety (some manuals will note the point at which a load will be compressed) - but compression may indeed dink with precise length to ogive / overall length. You're going to discover that a few thousandths of OAL variation is common regardless of compression.

You can try "settling" the powder by tapping the charged case or even buzzing it with an electric toothbrush. That's a pita.

As far as actual experience with that bullet/powder combo is concerned, maybe @Rob01 will chime in - I know he's got something going this afternoon so it may be awhile. He shoots Hornady ELD-Ms in several calibers, including .308.

Finally, as mentioned above, "max" varies from gun to gun, test barrel to test barrel. That's why you see different min/max charges for a given bullet/powder combo from one loading guide to another. While I've seen some published max charges that kinda widened my eyes, for the most part manuals are conservative - think liability.

Hodgdon, for example, shows 40.0-40.4 grains H4350 for two different 140gr bullets, and one of them shows compressed. Spend a little time here on SH and you'll find the most common 6.5CM loads for 140gr bullets and H4350 are in the 41.2-41.7 range, and some people pour in another grain or more beyond that. Until you gain experience and learn more about pressure signs, it's probably best to follow the manual's start-at-minimum-and-work-up directives.

Good luck!
 
So after saving brass for 10 years I finally dived into the deep end with reloading this past year. It’s been 12 months of slowly gathering parts, I just tonight started my load development for Hornady .308 178 gr ELD’s.

Brass is once fired Federal from factory gold medal match.
Primers are Federal 210M large rifle primers
Bullets are Hornady 178 gr ELD’s
Powder is IMR 4064.

Using Hornady’s reloading manual it shows the range as 35.3 to 41.7 gr

View attachment 7818817

I started at the minimum and did one round each at .03 increments. From 35.3 gr to 40.2 my OAL was consistent at 2.170.
View attachment 7818819
As soon as I jumped to 40.5 I could feel and slightly hear the load compress. I measured it and it bumped my OAL to 2.174
View attachment 7818820
I loaded one more round at 40.8 gr and could feel and hear the load compress again. Checked the OAL and it had now bumped my OAL to 2.180. So at this point I stopped although Hornady lists max at 41.7.
View attachment 7818825


Questions:
Is .308 compressed ok?
Obviously I’ll start at the minimum when I fire them, but would you even bother attempting to shoot the 40.5 and 40.8 loads that I know are compressed and bumped my OAL?
Would my brass type, Federal, account for the load compressing almost a full grain before max?

First question is how did you get to 2.170" as your OAL to ogive measurement? How far off the lands is that? What is OAL from base to tip? It's should be at least 2.800". Reason I ask is that is OAL to lands is a good number to know. That way you can adjust off it but the ELDs are not jump sensitive so they don't need to be right at the lands. I usually load them at .020" off.

As mentioned compressed is fine as long as it's safe. Somethings can be done like using a drop tube which can settle the longer kernels into the case and they will settle more. Different brass can effect that as some have less internal capacity than others. LC usually has less and Winchester is usually close to the most. Federal is in the middle somewhere.
 
As mentioned, it’s likely the bullet and powder combo that isn’t going to work. Those 178 ELDMs are very long. Shoot 185 Juggs 🍻
 
First question is how did you get to 2.170" as your OAL to ogive measurement? How far off the lands is that? What is OAL from base to tip? It's should be at least 2.800". Reason I ask is that is OAL to lands is a good number to know. That way you can adjust off it but the ELDs are not jump sensitive so they don't need to be right at the lands. I usually load them at .020" off.

As mentioned compressed is fine as long as it's safe. Somethings can be done like using a drop tube which can settle the longer kernels into the case and they will settle more. Different brass can effect that as some have less internal capacity than others. LC usually has less and Winchester is usually close to the most. Federal is in the middle somewhere.
2.170 is .20 off the lands. That’s why I selected that OAL
 
So after saving brass for 10 years I finally dived into the deep end with reloading this past year. It’s been 12 months of slowly gathering parts, I just tonight started my load development for Hornady .308 178 gr ELD’s.

Brass is once fired Federal from factory gold medal match.
Primers are Federal 210M large rifle primers
Bullets are Hornady 178 gr ELD’s
Powder is IMR 4064.

Using Hornady’s reloading manual it shows the range as 35.3 to 41.7 gr

View attachment 7818817

I started at the minimum and did one round each at .03 increments. From 35.3 gr to 40.2 my OAL was consistent at 2.170.
View attachment 7818819
As soon as I jumped to 40.5 I could feel and slightly hear the load compress. I measured it and it bumped my OAL to 2.174
View attachment 7818820
I loaded one more round at 40.8 gr and could feel and hear the load compress again. Checked the OAL and it had now bumped my OAL to 2.180. So at this point I stopped although Hornady lists max at 41.7.
View attachment 7818825


Questions:
Is .308 compressed ok?
Obviously I’ll start at the minimum when I fire them, but would you even bother attempting to shoot the 40.5 and 40.8 loads that I know are compressed and bumped my OAL?
Would my brass type, Federal, account for the load compressing almost a full grain before max?

Yes, yes, yes.
 
You can use a funnel with a long drop tube to settle the powder lower in the case and go up to 41.7 grains cus your lower charges will be real slow. The 41.7 load will barely make 2600 FPS out of a 24” barrel.
 
2.170 is .20 off the lands. That’s why I selected that OAL

That 2.174 is considered BTO ( base to ogive ) ...not OAL also called COAL (over all length....cartridge over all length )...ie base to bullet tip measurement.

The question asked has been , what is your oal ? That number is needed ,to understand where you are and to give better advice.
 
Yup just wondering what the OAL is as if it's 2.750" at .020" off you have a super short freebore and if it's at the other end of the spectrum then you probably wouldn't be crushing. Just trying to help out and needing info.
 
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Yup just wondering what the OAL is as if it's 2.750" at .020" off you have a super short freebore and if it's at the other end of the spectrum then you probably wouldn't be crushing. Just trying to help out and needing info.
Yep.......he's new to this rabbit hole and doesn't have all the terminology down ,ensuring there's no miscommunication....... He will catch on with a little guidance....... Maybe ?
 
I think he’s doing fine.

OP, you’re doing exactly what I intentionally do. Load up the ladder into the first couple compressed rounds, then watch for pressure as you go. Nothing more irritating than loading to “book max,” go to the range, then get 100 fps slower than their BS rig because they lie/hedge bets about max and run stupid long barrels that somehow are always fast. When that happens I gotta go load up a whole NEW ladder that goes farther and I have to start from scratch because I don’t trust trust conditions will be the same days later.

As for compression safety: stick powders are compression-tolerant, ball powders are not. Honestly don’t recall about flake powders, I only use them in handgun rounds and those powders are so fast that you can’t enough in there to fill the case without blowing your hand off. I am not shy at all about compressed rifle loads using stick powder, but I always watch very carefully on my way up.

I support your process.
 
Manuals usually list what length barrel and other components they use for their tests. They usually are lower and slower than people can end up using as they are lawyer written.

OP if that is .020" off the lands then it is a shorter freebore. Not a bad thing but you will have to stay there. Try the drop tube and see if it helps. They are pretty cheap at Midway



You can also look at Hodgdon for loading data to use that and the other and average out info. Hodgdon doesn;t list IMR4064 with the 178 but does with the 175 so you can use that data. We did for many years before 178 data started showing up in manuals.

 
"Max" is kind of like that line from Pirates of the Caribbean..."they are more like guidelines rather than rules".
"Max" even in that reloading manual is for THEIR gun, THEIR barrel, THEIR environment, etc. None of that directly translates to absolute terms to all guns.

Even small things can cause pressures to 'become max'... if you use a powder that is heat sensitive, your max load if you are shooting in January can easily be different than your load shot in July. Using the same brass, same bullets, same powder, same gun... the 'max' is a moving target in many instances.

A compressed load is not necessarily a horrible thing, but I think you are getting way ahead of yourself. Some powders are simply a lot more bulky than others. Some brass has a lot less or more capacity than others. New brass can have a lower capacity than once fired brass. There are a ton of factors that can lead to a compressed load. With some variables they can be totally safe, but with others not so much.

However if you are new it's a good idea to stay away from the edges until you get a lot more comfortable.

What your question should be is 'what signs should I look for to detect over pressure?'. You got the right spirit but just the wrong question. The only way to know for sure is to actually shoot, not by just going 100% by the manual. Your max could be a whole lot lower than their max.

In other words don't get ahead of yourself. Just load up a few rounds at each charge weight and shoot them. When you do, after each shot check your brass for pressure signs. If you see pressure signs STOP shooting. And also on that note, save yourself a whole lot of problems by just loading the minimum number of rounds to do this test. You can easily do this with just a few rounds, not 100 rounds.

On that note one guy I know got gung ho and loaded like 10 rounds at each charge weight and had like 100 rounds. He ended up having to pull the bullets out of around half of them. In other words loading up too many rounds, especially in this stage, can cause you a lot more work.

Other people here really like to go to the utter maximum on everything. A lot of the time those same folks have been reloading a long time and know the risks involved. I however don't try to get to max all the time. A lot of the time you can find a really good shooting load well off of the listed maximums.
Yes, max loads are also hard on your gun. Be careful of min loads too! Loaded some easy shooting (min) 9mm loads for target practice. My gun didn’t cycle all the time.. Same load data, increased the min by .4 grs of powder, still way below max, works great. I could say the loads that don’t cycle are good practice for safely dealing with jams, but I would be lying! I’ll use those when I can shoot at the outside range. I’ve made some really dumb mistakes loading. Only advice I can give you is check, check, double check and have your load data in front of you at all times. Reloading is fun, not a race. Take your time. If you have no time, go buy some store bought ammo and relax.
 
Another thought I had is perhaps the bullet type, Hornady 178 ELD’s just isn’t a good fit for my particular rifle. It’s a custom LRI .308 1:10 24” barrel.

Sorry for some of the noob terminology. The reason I called it OAL is because that’s what Hornady calls the tool you use to measure the distance to your lands. I have four different .308 bullets. And used the Hornady OAL tool to measure the distance to the lands for all four bullets I have:

253D79F6-B61B-4712-B24B-43A026B65E5B.jpeg


As you can see the 178 ELD’s have the shortest distance by quite a bit. I took .20 off the numbers above so I would be .20 off the lands. I started with a practice piece of unprimed but resized brass and the first ELD bullet I seated measured 2.195 before I adjusted the Forster micrometer down. Just for fun though I put it in my gun to see if 2.195 would fit and I had measured wrong. But the bolt would not close. I couldn’t even get it all the way forward at 2.195.

And you guys are right. I was increasing by .3 grains, not .03. So it’s about 22-25 loaded rounds for each to go from just above min to max. Except for the ELD’s none of the other bullets had problems loading to max.
 
As far as COAL, you DID NOT say what rifle you are reloading for. Different systems ie; Tikka,Savage,the M1A/m-14 or after market magazines all allow for different OAL's. If you have only 1 rifle chambered in 308, let your magazine be your guide when it comes to MAX OAL.
Since precise amounts of IMR-4064 are your goal, then each charge has to be weighed and a drop tube as mentioned above isn't a problem to use.
Does anyone remember on the old forum someone posted a picture of a ""personal vibrator"" attached to his loading tray full of cases showing a powder charge that was near the case mouth ??
 
As far as COAL, you DID NOT say what rifle you are reloading for. Different systems ie; Tikka,Savage,the M1A/m-14 or after market magazines all allow for different OAL's. If you have only 1 rifle chambered in 308, let your magazine be your guide when it comes to MAX OAL.
Since precise amounts of IMR-4064 are your goal, then each charge has to be weighed and a drop tube as mentioned above isn't a problem to use.
Does anyone remember on the old forum someone posted a picture of a ""personal vibrator"" attached to his loading tray full of cases showing a powder charge that was near the case mouth ??
this is very very bad advice

he said he was measured .020 off the lands

loading at 2.860 or 2.955 depending on magazine could be catastrophic
 
Manuals usually list what length barrel and other components they use for their tests. They usually are lower and slower than people can end up using as they are lawyer written.

OP if that is .020" off the lands then it is a shorter freebore. Not a bad thing but you will have to stay there. Try the drop tube and see if it helps. They are pretty cheap at Midway



You can also look at Hodgdon for loading data to use that and the other and average out info. Hodgdon doesn;t list IMR4064 with the 178 but does with the 175 so you can use that data. We did for many years before 178 data started showing up in manuals.


Can’t use that data in Federal brass. They use Winchester brass which partially explains why it’s so high.
 
So after saving brass for 10 years I finally dived into the deep end with reloading this past year. It’s been 12 months of slowly gathering parts, I just tonight started my load development for Hornady .308 178 gr ELD’s.

Brass is once fired Federal from factory gold medal match.
Primers are Federal 210M large rifle primers
Bullets are Hornady 178 gr ELD’s
Powder is IMR 4064.

Using Hornady’s reloading manual it shows the range as 35.3 to 41.7 gr

View attachment 7818817

I started at the minimum and did one round each at .03 increments. From 35.3 gr to 40.2 my OAL was consistent at 2.170.
View attachment 7818819
As soon as I jumped to 40.5 I could feel and slightly hear the load compress. I measured it and it bumped my OAL to 2.174
View attachment 7818820
I loaded one more round at 40.8 gr and could feel and hear the load compress again. Checked the OAL and it had now bumped my OAL to 2.180. So at this point I stopped although Hornady lists max at 41.7.
View attachment 7818825


Questions:
Is .308 compressed ok?
Obviously I’ll start at the minimum when I fire them, but would you even bother attempting to shoot the 40.5 and 40.8 loads that I know are compressed and bumped my OAL?
Would my brass type, Federal, account for the load compressing almost a full grain before max?
Hmmm??? FYI . . . you're referring to the case base to ogive as OAL when OAL stands for over all length. To avoid confusion, you should use CBTO when referring to those measurements. But, in terms of the comparison you're doing, that's a valid way to get and ideas of the difference if your load compression is reaching the maximum allowed (where it just won't compress any further).

I assume you were initially loading your cases to the SAAMI 2.800 COAL, is that right? And the heavier charges were compressing you seated the bullets longer by .018 to reduce the compression?

First . . .yes, it's ok to compress a load to a certain point. I've done it. You just have to be careful how much it might increases pressure as you monitor it when firing them and moving to higher and higher loads. But, until you really know what you're doing, it's best not to play with compressed loads. IMHO.

By lengthening the distance of your seating, that's helps a lot in reducing and mitigating the overpressure issue. For example, using 41.7 grs of IMR-4064 with the 178 ELD COAL at 2.800 fills the case to ~ 107% of case capacity put pressure above SAAMI max to ~68,800 psi. Increasing the COAL to 2.818 put it as ~106% of case capacity with pressure reduced to ~67,600 psi. So, that's still significantly above SAAMI max. As the charge weights move up during testing, I'd be looking close for pressure signs well before this load.

If you had enough freebore and/or mag length to seat the bullet much longer, then that load might become much safer to fire and give you the velocity you might be looking for. As an example, again, if the cartridge was seated with a COAL of 2.895, the case capacity would be at ~103% and pressure reduced to just over SAAMY max (like something around 63,000 psi). If you have enough freebore and mag capacity, you might even be able to go with much longer COAL.

My calculations are done in my QuickLoad app using data from my use of IMR-4064 in Federal brass which likely has a little different burn rate that your lot of 4064. Also, these calculations are based on a temperature of 75°F and the numbers can change if your temps are significantly different.
 
"Max" is kind of like that line from Pirates of the Caribbean..."they are more like guidelines rather than rules".
"Max" even in that reloading manual is for THEIR gun, THEIR barrel, THEIR environment, etc. None of that directly translates to absolute terms to all guns.

Even small things can cause pressures to 'become max'... if you use a powder that is heat sensitive, your max load if you are shooting in January can easily be different than your load shot in July. Using the same brass, same bullets, same powder, same gun... the 'max' is a moving target in many instances.

A compressed load is not necessarily a horrible thing, but I think you are getting way ahead of yourself. Some powders are simply a lot more bulky than others. Some brass has a lot less or more capacity than others. New brass can have a lower capacity than once fired brass. There are a ton of factors that can lead to a compressed load. With some variables they can be totally safe, but with others not so much.

However if you are new it's a good idea to stay away from the edges until you get a lot more comfortable.

What your question should be is 'what signs should I look for to detect over pressure?'. You got the right spirit but just the wrong question. The only way to know for sure is to actually shoot, not by just going 100% by the manual. Your max could be a whole lot lower than their max.

In other words don't get ahead of yourself. Just load up a few rounds at each charge weight and shoot them. When you do, after each shot check your brass for pressure signs. If you see pressure signs STOP shooting. And also on that note, save yourself a whole lot of problems by just loading the minimum number of rounds to do this test. You can easily do this with just a few rounds, not 100 rounds.

On that note one guy I know got gung ho and loaded like 10 rounds at each charge weight and had like 100 rounds. He ended up having to pull the bullets out of around half of them. In other words loading up too many rounds, especially in this stage, can cause you a lot more work.

Other people here really like to go to the utter maximum on everything. A lot of the time those same folks have been reloading a long time and know the risks involved. I however don't try to get to max all the time. A lot of the time you can find a really good shooting load well off of the listed maximums.
What he said. Especially the parts where Max is a moving target, and not having to shoot max loads all the time. No longer a shooter that could ever hope to be ‘competitive’ in shooting sports, I find medium loads often work better than fine, and as always are easier on the gun, easier on the shooter and moderately easier on the wallet.

A good example. I once owned a Kimber Predator. Possibly the nicest firearm I ever owned. I use multiple manuals to check loads and was satisfied that the load listing within the manual of the company that made the bullets was safe at starting to mid-range loads. Tested those loads in what I thought was all weather conditions. Shooting a Match in July, with those mid range loads, I ran into serious pressure issues. So, be respectful of what you shoot.

yep I am sure I have repeated this story, but it is perhaps the story that most needs to be repeated.
 
Hmmm??? FYI . . . you're referring to the case base to ogive as OAL when OAL stands for over all length. To avoid confusion, you should use CBTO when referring to those measurements. But, in terms of the comparison you're doing, that's a valid way to get and ideas of the difference if your load compression is reaching the maximum allowed (where it just won't compress any further).

I assume you were initially loading your cases to the SAAMI 2.800 COAL, is that right? And the heavier charges were compressing you seated the bullets longer by .018 to reduce the compression?

First . . .yes, it's ok to compress a load to a certain point. I've done it. You just have to be careful how much it might increases pressure as you monitor it when firing them and moving to higher and higher loads. But, until you really know what you're doing, it's best not to play with compressed loads. IMHO.

By lengthening the distance of your seating, that's helps a lot in reducing and mitigating the overpressure issue. For example, using 41.7 grs of IMR-4064 with the 178 ELD COAL at 2.800 fills the case to ~ 107% of case capacity put pressure above SAAMI max to ~68,800 psi. Increasing the COAL to 2.818 put it as ~106% of case capacity with pressure reduced to ~67,600 psi. So, that's still significantly above SAAMI max. As the charge weights move up during testing, I'd be looking close for pressure signs well before this load.

If you had enough freebore and/or mag length to seat the bullet much longer, then that load might become much safer to fire and give you the velocity you might be looking for. As an example, again, if the cartridge was seated with a COAL of 2.895, the case capacity would be at ~103% and pressure reduced to just over SAAMY max (like something around 63,000 psi). If you have enough freebore and mag capacity, you might even be able to go with much longer COAL.

My calculations are done in my QuickLoad app using data from my use of IMR-4064 in Federal brass which likely has a little different burn rate that your lot of 4064. Also, these calculations are based on a temperature of 75°F and the numbers can change if your temps are significantly different.

I have not used COAL in anyway to determine my loading depth. Everything I read online said don’t use that because bullets OAL can very even within the same box and you can inadvertently have some loaded bullets .20 off the lands, others .10 and others touching the lands if you only used COAL. I set my Forster micrometer seater to put my OGIVE .20 off the lands for this particular bullet. When I got up to my highest load - 40.8 grains, and I seated the bullet, it measured at 2.180. So the seater did not push it down to the 2.170 it was supposed to. Again, I believe because of the amount of powder in the case. I never adjusted the seater to seat the bullet higher. At 2.180 it is now only .10 off the lands.
 
I have not used COAL in anyway to determine my loading depth. Everything I read online said don’t use that because bullets OAL can very even within the same box and you can inadvertently have some loaded bullets .20 off the lands, others .10 and others touching the lands if you only used COAL. I set my Forster micrometer seater to put my OGIVE .20 off the lands for this particular bullet. When I got up to my highest load - 40.8 grains, and I seated the bullet, it measured at 2.180. So the seater did not push it down to the 2.170 it was supposed to. Again, I believe because of the amount of powder in the case. I never adjusted the seater to seat the bullet higher. At 2.180 it is now only .10 off the lands.

Variations depend on the bullet type as BTHPs have a lot as the tip is open but the ELDs have less. Going off the Ogive is the best way anyways.

One question, what is your neck tension? If it's not enough then that could be causing the slipping of the bullet when trying to compress. Your seater may be pushing it down to 2.170 but the powder pushes it back up. Again getting a drop tube will help that a lot.
 
Variations depend on the bullet type as BTHPs have a lot as the tip is open but the ELDs have less. Going off the Ogive is the best way anyways.

One question, what is your neck tension? If it's not enough then that could be causing the slipping of the bullet when trying to compress. Your seater may be pushing it down to 2.170 but the powder pushes it back up. Again getting a drop tube will help that a lot.
I’ll have to check neck tension tonight. I don’t think it’s too light, as I pulled the bullets from 3 unprimed cases I was testing with when I first set up the seater and with a hornady bullet puller it took some decent upward force on my co-ax’s handle to pull the bullets.
 
I have not used COAL in anyway to determine my loading depth. Everything I read online said don’t use that because bullets OAL can very even within the same box and you can inadvertently have some loaded bullets .20 off the lands, others .10 and others touching the lands if you only used COAL.
I don't use COAL to determine my loading depth either. And your right about how that can effect distance off the lands. But there's the same issue with referring to CBTO or BTO measurements since there's a great variance, especially if one's caliper insert is of a different producer . . . even greater than the measured variance in bullet's OAL. Then in terms of being off the lands, that can't tell anyone anything either unless one knows the length of the freebore since various chambers of readers are typically very different. At least when we know the COAL, we can then take our own tools and figure out better what the seating depth actually is and what kind of jump that might be for our own chambers. Stating COAL's isn't perfect to communicate how one's cartridges are loaded, but it's the one with the least variance to the public at large.

I set my Forster micrometer seater to put my OGIVE .20 off the lands for this particular bullet. When I got up to my highest load - 40.8 grains, and I seated the bullet, it measured at 2.180. So the seater did not push it down to the 2.170 it was supposed to. Again, I believe because of the amount of powder in the case. I never adjusted the seater to seat the bullet higher. At 2.180 it is now only .10 off the lands.
I have two .308 caliper inserts, one from Hornady and another from Sinclair. I like my Sinclair as it's contact diameter is much closer to that of my .308 lands than the Hornady's. The difference in their contact point is ~ .110". And my Hornady insert is significantly different in diameter from my shooting buddy's Hornady. So, when stating a CBTO measurement of 2.170, I have no idea how deep the base of your bullet is really seated in that .308 case because caliper inserts are just not uniform. If I knew the COAL, then I could figure it using my own caliper with the understanding of bullet variances like .010.
 
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Hmmm??? FYI . . . you're referring to the case base to ogive as OAL when OAL stands for over all length. To avoid confusion, you should use CBTO when referring to those measurements. But, in terms of the comparison you're doing, that's a valid way to get and ideas of the difference if your load compression is reaching the maximum allowed (where it just won't compress any further).

I assume you were initially loading your cases to the SAAMI 2.800 COAL, is that right? And the heavier charges were compressing you seated the bullets longer by .018 to reduce the compression?

First . . .yes, it's ok to compress a load to a certain point. I've done it. You just have to be careful how much it might increases pressure as you monitor it when firing them and moving to higher and higher loads. But, until you really know what you're doing, it's best not to play with compressed loads. IMHO.

By lengthening the distance of your seating, that's helps a lot in reducing and mitigating the overpressure issue. For example, using 41.7 grs of IMR-4064 with the 178 ELD COAL at 2.800 fills the case to ~ 107% of case capacity put pressure above SAAMI max to ~68,800 psi. Increasing the COAL to 2.818 put it as ~106% of case capacity with pressure reduced to ~67,600 psi. So, that's still significantly above SAAMI max. As the charge weights move up during testing, I'd be looking close for pressure signs well before this load.

If you had enough freebore and/or mag length to seat the bullet much longer, then that load might become much safer to fire and give you the velocity you might be looking for. As an example, again, if the cartridge was seated with a COAL of 2.895, the case capacity would be at ~103% and pressure reduced to just over SAAMY max (like something around 63,000 psi). If you have enough freebore and mag capacity, you might even be able to go with much longer COAL.

My calculations are done in my QuickLoad app using data from my use of IMR-4064 in Federal brass which likely has a little different burn rate that your lot of 4064. Also, these calculations are based on a temperature of 75°F and the numbers can change if your temps are significantly different.
It also is a good note to point out that brass can have much differing thickness to where case capacity can vary quite a bit. I'm not familiar with the quickload program like I am the GRT. but grt uses case capacity in h2o grain weight and for example a case that holds 42 grains of h2o vs 43.5 grains can make a massive pressure difference. Also how tight or loose your chamber is and what sizing die you use. It's really a big black deep hole but we love it
 
It also is a good note to point out that brass can have much differing thickness to where case capacity can vary quite a bit. I'm not familiar with the quickload program like I am the GRT. but grt uses case capacity in h2o grain weight and for example a case that holds 42 grains of h2o vs 43.5 grains can make a massive pressure difference. Also how tight or loose your chamber is and what sizing die you use. It's really a big black deep hole but we love it
GRT is essentially the same as QuickLoad, only with a few additional features, and the use of case capacity and usable case capacity is a critical element to the program . . . as you've point out. So, yes, you're right about the effect for differing case thicknesses. Since I've measure various lots of Federal brass (which the OP was referring to), I use the case capacity that's typical for Federal brass.

FYI: Here's an example of the QuickLoad app's main screen:

168 SMK - Acc4064.jpg
 
GRT is essentially the same as QuickLoad, only with a few additional features, and the use of case capacity and usable case capacity is a critical element to the program . . . as you've point out. So, yes, you're right about the effect for differing case thicknesses. Since I've measure various lots of Federal brass (which the OP was referring to), I use the case capacity that's typical for Federal brass.

FYI: Here's an example of the QuickLoad app's main screen:

View attachment 7955891
Ya I have it and tried it out but I really liked the format and the OBT that GRT uses so I basically just haven't used quickload