Controlling OAL Variation

[compujas 21]

When reloading, how do you control your OAL variation and what is acceptable? Whenever I'm loading, I'll set the bullet seater and measure the rounds to see if it needs to be adjusted, but they seem to vary up to .010" or more from each other. Most tend to be within a .005" range, but I'll get some that are more than .010" above my OAL and then some that are .003" below for example. When you run into this, do you set the longer ones aside and seat them a little deeper or do you just accept them? Or do you all run progressives and not even have a clue (or care)? This question is mostly for pistol, but could apply for rifle as well since I load match-grade .308 for accuracy.

 

In case anyone is going to ask, I have a Lee Breechlock with Lee dies.

[tony357 386]

I have that also not that much of a spread.. your ok as long as you are not too far below the min. so set your die up so it will not go below the min AOL for your load.

[Shocker 151]

You also have to be sure that it's actually an OAL variance versus a primer sticking up above flush. Are you using sorted brass?

 

I have a Lee as well but when I'm doing pistol I only measure the first few...after I know I'm pretty close to where i want to be I'll bang out a few hundred and only measure here and there.

 

Rifle I measure every single one and I see +/- 0.002 with sorted brass.

[Regulator72 80]

Not to threadjack, but Here's a question, dumb one I think, but when measuring oal using say a digital micrometer/caliper, what is the proper way to check? I mean, I know how to check but what type of pressure/force do you put on the micrometer in order to determine your oal? I feel as tho I can push hard enough to change the readings quite a bit. (Obviously its not pushing the bullet in farther)

[Pew Pew Plates 358]

Your OAL variation doesnt matter if you arent measuring with a bullet comperator. Your lengths from ogive to base may be dead on every time but bullet tips will vary. Tip variation doesnt matter since they dont touch anything... so measure from the ogive.

[Old School 611]

Your OAL variation doesnt matter if you arent measuring with a bullet comperator. Your lengths from ogive to base may be dead on every time but bullet tips will vary. Tip variation doesnt matter since they dont touch anything... so measure from the ogive.

 

1 Glenn People wouldn't believe the variation there is with even premium bullets. I always thought Seirra were the best and I actually find Hornady more consistant... Go figure...

[bry@n 195]

I see that my OAL is different when using a micrometer. I am using different cases and the rounds function through my guun, so I don't get out of wack with it. generally, the difference isn't a lot.

 

What is ogive?

[Regulator72 80]

I see that my OAL is different when using a micrometer. I am using different cases and the rounds function through my guun, so I don't get out of wack with it. generally, the difference isn't a lot.

 

What is ogive?

 

Hey buddy... I pretty much do the same with pistol, but getting into rifle reloads, I want to make sure I doing it right..

 

I read about ogive. Here...

 

http://www.accurateshooter.com/gear-reviews/hornady-oal-gauge-and-comparator/

[Old School 611]

If you set your seating die to give you a mean COL, as required, I doubt you'll have any problem.

 

Ogive, as has been mentioned, is the critical measurement and if you actually mearured it, because your

 

seating die seats on the ogive, you would be surprised how accurate it is.

[compujas 21]

Don, you shouldn't be putting much force on the caliper, just enough to get the blade to make contact. If you start putting a lot of force you're going to either deform the bullet or start pushing it into the case. Just a light touch to have the blade make contact is good.

 

Bryan, the ogive is the non-cylindrical portion at the front of the bullet, so where the body starts to taper down to a point/round/flat.

 

I have seen the comparators and looked into them, but then how do you translate a COAL from a manual into a length measured with a comparator?

 

I guess it sounds like I should just get the average COAL to be correct and not worry so much about the outliers. However, for example, last night I loaded 30 rounds of 9mm for load testing. My OAL was 1.090" (4.2gr Titegroup). I'd say I got probably 10 rounds between 1.088-1.093, 12 rounds between 1.094-1.099, and the last 8 between 1.100-1.110. So obviously they are extremely inconsistent (these were Hornady 115gr bullets by the way). So I wound up measuring every single one and sorting them and going back and reseating the high ones. Or would you assume that it's all variation in the bullet and leave them alone since they were seated by the ogive?

[Old School 611]

Don, you shouldn't be putting much force on the caliper, just enough to get the blade to make contact. If you start putting a lot of force you're going to either deform the bullet or start pushing it into the case. Just a light touch to have the blade make contact is good. Correct! But unlikely you will push the bullet into the case.

 

Bryan, the ogive is the non-cylindrical portion at the front of the bullet, so where the body starts to taper down to a point/round/flat. It's the last part of the bullet that is still the nominal diameter of that bullet.

 

I have seen the comparators and looked into them, but then how do you translate a COAL from a manual into a length measured with a comparator?

 

I guess it sounds like I should just get the average COAL to be correct and not worry so much about the outliers. However, for example, last night I loaded 30 rounds of 9mm for load testing. My OAL was 1.090" (4.2gr Titegroup). I'd say I got probably 10 rounds between 1.088-1.093, 12 rounds between 1.094-1.099, and the last 8 between 1.100-1.110. So obviously they are extremely inconsistent (these were Hornady 115gr bullets by the way). So I wound up measuring every single one and sorting them and going back and reseating the high ones. Or would you assume that it's all variation in the bullet and leave them alone since they were seated by the ogive? I'd leave it allone and just shoot them.

 

Remember, especially with lead bullets, to periodically clean your seating die as a build up of lead or other debris will shorten your COL.

[bry@n 195]

Good stuff guys. Thanks

[Socom 19]

on my 650 i use http://www.uniquetek.com/site/696296/product/T1230 toolhead clamp kit mine are usually minus .01 or plus .01 member on a progressive press that your oal will differ between the first few bullets until all stations have something in it..

[Brian B 2]

As Socom said,

 

do not measure rounds on a progressive unless all the stations are full for the best consistency. I see average oal variations of .005 if using the same brass, mixed brass does give me larger variations.

[Regulator72 80]

Awesome info, thanks guys... I'm using a 650 as well

[hd2000fxdl 422]

Not to threadjack, but Here's a question, dumb one I think, but when measuring oal using say a digital micrometer/caliper, what is the proper way to check? I mean, I know how to check but what type of pressure/force do you put on the micrometer in order to determine your oal? I feel as tho I can push hard enough to change the readings quite a bit. (Obviously its not pushing the bullet in farther)

 

I would get a bunch of different drills in different sizes, practice on them for a little while until you can repeat the same measurement on each one. This just like trigger control does take a little bit of feel and muscle memory.

[hd2000fxdl 422]

As Socom said,

 

do not measure rounds on a progressive unless all the stations are full for the best consistency. I see average oal variations of .005 if using the same brass, mixed brass does give me larger variations.

 

I see about the same on the very max side. I grew up with my father having a machine shop so I got used to QC checking. Being i am new to reloading I am taking my time on my 650, at the press I am closer to only 300 to 350 rounds per hour when I get going. The only reason I'm that slow is I look at each station every pulll of the handle, and I measure each round with dial calipers and after I measure I stand the bullets up to use a cae gauge to check them before I put them in their boxes for use.

 

To me +/- .005 is too much and have to look at the clamp kit, when I am running +/- .001 even .002 I will be able to QC every 10th or 25th round and not every one like I do now.

[Socom 19]

I see about the same on the very max side. I grew up with my father having a machine shop so I got used to QC checking. Being i am new to reloading I am taking my time on my 650, at the press I am closer to only 300 to 350 rounds per hour when I get going. The only reason I'm that slow is I look at each station every pulll of the handle, and I measure each round with dial calipers and after I measure I stand the bullets up to use a cae gauge to check them before I put them in their boxes for use.

 

To me +/- .005 is too much and have to look at the clamp kit, when I am running +/- .001 even .002 I will be able to QC every 10th or 25th round and not every one like I do now.

 

hd2 i do recommend the kit its great i mean if youd like i shall have you over to check out my machine and answer all the question you have about it!

 

PM me

[Maksim 1,504]

Lee 4 die set, on 40 cal, I never have a variation over .003, if that. No clamps, etc.

 

The only time I had issues were with rcbs 3 piece dies.

 

Once I hqve it loaded, they go into 100 round boxes bullet down for a consistency check and to look at primers. Then if a big match, I will chamber check every round.

 

Bullet wise, mg and pd have all been accurate, and at most .2 grains on the low side from time to time on 180 grain.

 

 

[Jon 264]

I always see some variation, but my loads aren't max, and my OAL is forgiving enough to work in my guns +/- .008 or so, thus I don't let the variation get to me.

[Socom 19]

I always see some variation, but my loads aren't max, and my OAL is forgiving enough to work in my guns +/- .008 or so, thus I don't let the variation get to me.

 

thats just to ridiculous for me and sloppy

[Jon 264]

thats just to ridiculous for me and sloppy

 

My loads always make power factor, are super reliable, and consistent enough to where I see no need to do any more work.

[hobobluz 0]

I guess it sounds like I should just get the average COAL to be correct and not worry so much about the outliers. However, for example, last night I loaded 30 rounds of 9mm for load testing. My OAL was 1.090" (4.2gr Titegroup). I'd say I got probably 10 rounds between 1.088-1.093, 12 rounds between 1.094-1.099, and the last 8 between 1.100-1.110. So obviously they are extremely inconsistent (these were Hornady 115gr bullets by the way). So I wound up measuring every single one and sorting them and going back and reseating the high ones. Or would you assume that it's all variation in the bullet and leave them alone since they were seated by the ogive?

Wow! That is a huge variation. I assume your gun cycles normally, and you are nowhere near the minimum COL for that particular load. Seems like something is wrong with your die/press. As you are not running a progressive press you don't have to worry about shell plate issues. I would check first your shell holder. Take it out and insure there are no burrs or powder that would keep the holder from remaining perfectly flat relative to the bore stroke. Reinstall the holder and make sure it doesn't rock. If it does there is a problem. Next, is the seating die itself and the new breech lock mechanism. Remove the die from the press. Using a q-tip, clean the inside of the die that makes contact with the bullet. Insure there are no burrs, copper or junk inside. It is critical that this is clean and smooth. Ok, now install the die. With the breech lock system, make sure the "button" is in the groove and is UP completely. After you have set your COL, make sure the locking ring on the die is in fact screwed tight. It has to be just a little more than hand tight, but don't over do it.

The last thing that I would check is you "crimp". You have to "crimp" just firmly enough to hold the bullet.

You simply have too much variation there. COL also affects internal pressure, so it is something to be worried about, only if COL is pressing the minimum. On the other side, if COL is too long, you only have to worry about magazine loading, and breech lenght.

[compujas 21]

I loaded another 90 rounds last night, targeting COL 1.120". I measured every single one and saw them range from about 1.118-1.126 (going on memory and didn't record the measurements). This is also after I cleaned out all of my dies (they really didn't appear to need a cleaning, but I did anyway). I also measure the COL before I crimp since there's no reason the crimping should move the bullet anyway.

 

How do you determine what your COL for a load should be? Most loading manuals I've seen only show a single number, not necessarily noted as min or max, so I just target it +/-.005 and figure it's close enough.

[Socom 19]

I loaded another 90 rounds last night, targeting COL 1.120". I measured every single one and saw them range from about 1.118-1.126 (going on memory and didn't record the measurements). This is also after I cleaned out all of my dies (they really didn't appear to need a cleaning, but I did anyway). I also measure the COL before I crimp since there's no reason the crimping should move the bullet anyway.

 

How do you determine what your COL for a load should be? Most loading manuals I've seen only show a single number, not necessarily noted as min or max, so I just target it +/-.005 and figure it's close enough.

 

and you are using a lee SS press? i have one that i work up lead loads on and mine is pretty much nail on the head with oal most ss presses do idk how in the **** you are gettin variables on a ss press

[hd2000fxdl 422]

I loaded another 90 rounds last night, targeting COL 1.120". I measured every single one and saw them range from about 1.118-1.126 (going on memory and didn't record the measurements). This is also after I cleaned out all of my dies (they really didn't appear to need a cleaning, but I did anyway). I also measure the COL before I crimp since there's no reason the crimping should move the bullet anyway.

 

How do you determine what your COL for a load should be? Most loading manuals I've seen only show a single number, not necessarily noted as min or max, so I just target it +/-.005 and figure it's close enough.

 

I also have been loading to 1.120 for my .40 for my CZ 75-TS, it works well in that gun, I do know if I increase that to 1.125 I am still good but I tried 1.30 it didn't cycle the gun right and had FTE's and stovepipes. Each gun may be different, so like they say load to the PF you are looking for and what works best in the gun you using them in. These are for my Minor loads, will be working up some Major loads when I finish off this last run of 2K Minor.

[Maksim 1,504]

Harry, 1.2 is typically max in Sti, and the max in mine for mags to feed is 1.145

[hobobluz 0]

I loaded another 90 rounds last night, targeting COL 1.120". I measured every single one and saw them range from about 1.118-1.126 (going on memory and didn't record the measurements). This is also after I cleaned out all of my dies (they really didn't appear to need a cleaning, but I did anyway). I also measure the COL before I crimp since there's no reason the crimping should move the bullet anyway.

 

How do you determine what your COL for a load should be? Most loading manuals I've seen only show a single number, not necessarily noted as min or max, so I just target it +/-.005 and figure it's close enough.

Well this is better. You have a .008 variation and this is acceptable variation, as long as you don't go below the COL listed for that load. In your previous post, you had a variance of .022 thousandths of an inch, which is completely unacceptable.

 

The manuals give the minium COL for a particular powder load and bullet. The SAMMI standard maximum COL for 9mm is 1.169. You can go up to this as long as you can get the bullets into your mag, and they will seat flush or lower in your breech. To check this take the barrel OUT of the gun and drop a bullet in the barrel. It should seat flush or lower in the breech. Also, it should drop out of its on accord when you tip the barrel to remove the bullet.

 

I am confused about your crimping statement. If you are using the Lee 3 die system, then the die that seats the bullet to the COL also does the taper crimp in the same operation. So there is no need to "measure the COL before" you crimp.

[compujas 21]

I use the Lee 4 die set. It has a separate factory crimp die.

[hobobluz 0]

I use the Lee 4 die set. It has a separate factory crimp die.

Ah, ok, you are good to go then.

Your variation of .008 (which is +/- .004) is acceptable. Just never go below the listed COL and you will be fine.