Bullet seating depth/COL giving me fits!

[NJM15]

In my case almost every col will vary its a revolver there is a pretty big range if its not sticking out the front of the cylinder its not too long, of course stick to the do not exceed col info I checked a new round (40 s&w) and the col was not even close to the recommended max COL, and the and the length varied from one to another

 

[ken158]

Been reloading since I was a teenager.... A stickler for perfect reloads due to years of target and benchrest shooting - the OAL was always a pain UNTIL I started setting my dies off the ogive of the bullet and stopped worrying about measured OAL due to the slight imperfections associated with bullets.

 

[fredj338]

The little differences will have no bearing on your shooting. Once you get to rifle loading, and are competing in Benchrest, they you may need to pay this close of attention.

Not even then.

 

[Alk8944]

Do yourself a favor and stop measuring OAL! For automatics and rifles it has validity, but not for revolvers. If you are using cannelured bullets simply seat to approximately the center of the cannelure and forget about it!

 

[SLT223]

If you really want to see some wonky COL's, load up some pulled down jacketed soft point slugs. That'll teach not to bother pulling out your calipers

 

[daniel lawecki]

Your ammo is fine the tolerance is in specs your feel with calipers could be off that much. I check the first 3 the resume reloading. once the dies are locked down tight your good to go.

 

[noylj]

You're over-thinking and over worrying—it just isn't that important. If you can hold the COL variation to +/- 0.003", you are doing well.
As far as your picture goes, as long as the case mouth in within the crimp groove, you are a good as gold—crimp and be done.
1) Bullets vary that much. Measure your bullets.
2) The base of the case can vary—manufacturing tolerances, ejection, bouncing on the ground, etc. Measure a case all around (and not across the whole case, but just the edge of the rim to case mouth) and see how the case length can vary.
3) EVERY press has some flex. Flex will cause a variation.

 

[Ivan the Butcher]

Personally, I think you are brave in admitting that you lack self control and patience. You don't want the frustration of reloading equipment without every possible component available, to upset your piece of mind. And I can tell you that having reloading equipment and supplies in your home but unloaded will leave you batty! Then the problem of your children coming to visit and stay for reloading and dinner, that will destroy the whole idea of kicking them out in the first place. Buddys would want to spend time with you, and even worse go shooting with you. One other problem is that in the future the prices will go up, and you won't b able to load for 4 cents a round like I did in the early 80's. Who cares how much you save not buying commercial ammo. You will have all the frustration of not doing reloading for the prices of 30 years ago. My hat is off to you for saving all the frustration that would otherwise be coming your way. Ivan

PS One problem I am facing now is all my brass is full and I have ample powder, primers and bullets for thousands of reloads. But the weather is so bad I can't make anymore empties and I'm out of storage space for more reloads. Yes it is a total life of frustration you are avoiding!

 

[yeti]

A family member came to me to ask about reloading equipment choices. Knowing the family member's personality and get 'er done as quick as possible general attitude, I said "you are not cut out for reloading...don't do it." He was mad at me.

This thread is refreshing. Unlike my family member, you have the proper attitude and disposition to be a great reloader, Hillbilly77.
We should always worry about the quality and consistency of our loads. These concerns will keep you safe and make your loads accurate. However...minor COAL variance to that degree is beyond your control.

 

[mikld]

I forgot to mention, I am using a single stage press and I seat and crimp in two different steps.

It sounds like I'm doing ok?

I'd say you're OK. It's hard for a "perfectionist" new reloader not to overthink some aspects of reloading. My OCD drove me nuts at times. I once got on a roll and weighed about 250 bullets and separated them into three piles. OK for a bench rest shooter, but I was working with cast bullets in my .44 magnum revolver . Some minor differences jes don' matter...

 

[joeintexas]

Yeah, what they said. I would shoot them. They look fine.

 

[glowe]

I forgot to mention, I am using a single stage press and I seat and crimp in two different steps.

Do you not have a crimp on your standard die set? You have a different die for crimp? Just curious, since I can find no difference in handgun loading when using a standard die seating and crimper in the same die in one step, instead of a seperate crimper. Just an an extra step that I can find little value in doing. Some rifle loads will perform better with a seperate crimp die, but handgun loads are very forgiving. I measure COL in terms of fractions of inches and not thousands of an inch.

 

[Vortec MAX]

The pictures appear to show uncrimped rounds. I find that the crimp process changes the OAL slightly, so that will drive you crazy too

Just put the word "about" in front of your target OAL. Since your seating die does not put pressure right on the very end of the bullet, but rather part way down the shoulder, variations in bullet geometry will cause some differences in your OAL.

Mike

 

[noylj]

Just to add to my comments:
>As per my loading manual, I set the COL to 1.60"

What makes you think that is the COL for your gun? That is simply the COL used for testing. For most testing, the lab uses a shorter than normal COL so pressures will go up faster than the average reloader will find in their gun. So, you can consider that to be the minimum COL the data applies to for the EXACT bullet they used.
COL depends on several factors, most of which the test lab has no knowledge of:
1) the EXACT ogive of the bullet being used (and don't think the ogive doesn't change--bullet manufacturer's seem to like to change their bullet geometry/design and not notify any one).
2) The cartridge length that fits in your magazine and when the magazine lips release the round to be fed. If the COL is too lip with respect to when the magazine released the round, the round tends to "jump up" and jam at the top of the barrel and if too long will simply smash into the feed ramp.
3) the feed ramp geometry.
4) the chamber and lede/rifling of the barrel.
In general, the "best" COL is the longest that feeds and chambers 100%.

From Ramshot Powders:
SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH "COL"
It is important to note that the SAAMI "COL" values are for the firearms and ammunition manufacturers industry and must be seen as a guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as
1) magazine length (space),
2) freebore-lead dimensions of the barrel,
3) ogive or profile of the projectile and
4) position of cannelure or crimp groove.

• Always begin loading at the minimum "Start Load".
• Increase in 2% increments towards the Maximum Load.
• Watch for signs of excessive pressure.
• Never exceed the Maximum Load.

 

[Snolan4571]

Hey been reloading since 1975 and I still overthink things at times. As stated - center of cannelure will do it. Wait till you do your first necked rifle cartridge. PITA to NOT Over Think everything.

 

[Hillbilly77]

Hey been reloading since 1975 and I still overthink things at times. As stated - center of cannelure will do it. Wait till you do your first necked rifle cartridge. PITA to NOT Over Think everything.

I already did some last fall.
I ended up pulling several bullets that did the same thing to me.
I'm probably a lot pickier than I need to be.
But, I started reloading primarily to get consistent, repeatable results and accuracy. I got sick of inconsistent factory ammo.

With my deer rifle, I'm not happy to hit a paper plate at 100 yards. I want nickel or quarter-sized groups at 200 yards.
My loads aren't quite there yet, but I was getting 3-4" groups at 200 - plenty accurate for a deer rifle, but I know it can do better.

 

[RIDE-RED 350r]

IME, I get a slightly different result when seating in small increments, than when seating all in one stroke. I've seen this with many different types of bullets. The seating in one stroke almost always results in a slightly shorter OAL. When I'm doing the small increments, I stop when I think it's just a tad longer than what I want. So, when I do the one stroke seating, it seats exactly where I want it. Like others wrote, a couple-few thousandths is no big deal.

I have noticed this exact phenomenon myself...

I have been reloading for about 2 years now, and am just as picky as Hillbilly with just about every aspect of my reloading. This thread has been a good read for me and the advice given to Hillbilly has been just as helpful to me.

One theory I have about this, yay or nay: We both use a Hornady Lock N Load press. The bushings are O-ringed as most of you know. I was thinking that this little oddity might be attributed to the O-ring under the Lock N Load bushing giving that little bit of slack??? Was thinking of getting a second press, (RCBS) to try seating with and see if this still occurs... But after reading this, I think I'll pass on the whole experiment.

 

[ageingstudent]

I have a problem that I could use some help with.

When I am working up a load, when seating the first bullet, I adjust the seating die a bit at a time until I get the right depth/COL.
Then, the very next bullet seats a few 1/1000'ths too deep.

This has happened to me with different calibers, both rifle and pistol loads.

Right now, I am working up some .44 Magnum loads.
As per my loading manual, I set the COL to 1.60". The second bullet I seated went to 1.5970. This has happened multiple times.

I find myself backing the adjustment out on the die and slowly working to the correct seating depth on each round, which seems like a waste of time.

My question is, am I doing something wrong, or does this "just happen"? Is .003" enough to worry about, or am I being too finicky?

At the risk of being a nerd, it is something that "just happened." I have the same thing happen when I am setting up for a different OAL.

This quote from the hyper physics website explains what happens when you gradually adjust that OAL on the first bullet and then the next one comes out a little short:

"...the amount of force required to move an object starting from rest is usually greater than the force required to keep it moving at constant velocity once it is started."

Simplified, when you seat that second bullet you are making one stroke all the way and it is moving into the case much more easily that the one that you seated in increments so it goes a hair further into the case because there is less friction.

It's an interesting physical phenomenon. I bet if you accelerated or slowed your pull as you seat the projectile your OAL would lengthen or shorten accordingly.

This stuff gets me all fired up. Fascinates me. Great website that I use often:

Force

And no that amount of variance is not bad. Well within safe limits. Props for paying attention to details buddy

 

[uechikid]

I'm glad I found this thread. Being new to reloading and wanting to make sure I do everything right, I too noticed a variation in COL when I was loading some .40 S&W the other day. I feel better knowing that small variations in COL is normal.

 

[ArchAngelCD]

I'm guessing by now you realize you are doing well and you are making good ammo. If all the variation I got was .001" I would be very happy! Totally normal and totally safe. Stop worrying and go shoot your ammo...