newbie OAL variation question

luckey

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Hi, I have finally setup my 550B and started to load my first test batch and got some variations on the OAL. Could you please let me know if it's ok.
the details are as below.

1. press: 550B
2. Dies, lee carbide 4-die set 45ACP, except Dillon powder die as I am using Dillon powder measure.
3. Bullet: Campro 45cal 230gr Plated RN/FCP
4. Brass, mixed headstamped range brass
5. Primer: Dominion large pistol primer
6. Powder: HS-6
7. Pistols: Glock 41 Gen 4 & SR1911

I first loaded 3 dummy rounds, long to flush, against the barrels. All 3 rounds come out consistent with the OAL. So, my test batch was to settle at OAL: 1.235" with 7.2, 7.4, 7.6, 7.8 and 8gr powder charge(from all the manuals, the range is 6.7gr to 8.2gr). I was trying to load 20-round each, total of 100 rounds to test on both pistols I have.

Then the results out of the 26 I loaded so far, after checked one-by-one, everything else(primer seating, powder charge/flare and crimp) is very consistent, except OAL which only has 7 right @ 1.235", others are ranging from 1.230" to 1.241". Is it safe to shoot them, or I have to pull them? I did drop them in the barrels one-by-one without any issue and also loaded with magzine with no issues(not in the gun of course). The bench is solid with no flex, so it should not be the cause of this.

Thanks!
 
It's the variance in manufacturing . What you should be measuring is the OGIVE of the round. Some bullets are longer or shorter than others even though they weigh the same. However, the distance between part of the bullet that touches the lands and the lands itself should be consistent.
 
thanks. as a newbie, I am not sure I understand the terms you used. what does 'the distance between part of the bullet that touches the lands and the lands itself should be consistent." mean?
I will measure the ogive, but thoguht if I setup the dies correctly, they should be the same as the die will push the longer bullet down a little further to archieve the set OAL, right?

It's the variance in manufacturing . What you should be measuring is the OGIVE of the round. Some bullets are longer or shorter than others even though they weigh the same. However, the distance between part of the bullet that touches the lands and the lands itself should be consistent.
 
press is 550b as mentioned in the details. for seating, I tried both.
one-by-one on station 3(seating die), or 4 stations all in use as progressive. this is the reason I bought 550 over 650 because I can use it as a single stage if I want, especially during newbie period.
I check every single round I load and really couldn't understand what went wrong. Maybe my pull is inconsistent? but that doesn't explain why all other 3 stations have no issues at all.

Your OAL should not vary that much.

What is your loading process? Are you seating all the bullets at the same time or doing them in batches ?
 
Your bullet seating die does not push on the tip of the bullet. The ram is cupped and it pushes on the bullet somewhere on the curved section of the bullet. If there are variations in the bullets above the point where the ram pushes, these variations are what causes the COAL variation.

For accuracy, these variations mean nothing. But one of your requirements is that the longest round must still fit the mags. And your rounds are long enough that one could hang up in the mag, so seat deeper.

Buy a box of round nose FMJ, and try those to see if you get variation in COAL. If you don't, you will know the issue was with the bullets.

For the ones you have now, turn your seater stem in a half rev. That should do it.
 
ok. evidently, I haven't read enough, yet. :)

based on the google search, I guess you are saying that I should measure from the base of the complete cartridge up to the bullet where the ogive starts? they should be the same? I found an article online talking about rifle rounds. Is it the same for pistol rounds? thanks

http://www.bergerbullets.com/effect...coal-and-cartridge-base-to-ogive-cbto-part-2/

thanks. as a newbie, I am not sure I understand the terms you used. what does 'the distance between part of the bullet that touches the lands and the lands itself should be consistent." mean?
I will measure the ogive, but thoguht if I setup the dies correctly, they should be the same as the die will push the longer bullet down a little further to archieve the set OAL, right?
 
Hi Ganderite,

thanks. basically, right now, both the "long"(1.240") and the short (1.23") have no problema with my mags and barrels compared to the 1.235"s I got.
then assuming the issue is with the bullets with different sizes/shapes, my concerns/questions are more on the safety side, rather than accuracy. Are they still safe to shoot?
I know unless the OAL is at the extreme end(I meant the bullet is not seating too deep or high), it should not affect pressure too much, not for pistol anyway, but as a newbie, I would like to check with the gurus first.
as mentioned above, I am doing test load from 7.2 to 8gr with 0.2gr incremental with HS-6.




Your bullet seating die does not push on the tip of the bullet. The ram is cupped and it pushes on the bullet somewhere on the curved section of the bullet. If there are variations in the bullets above the point where the ram pushes, these variations are what causes the COAL variation.

For accuracy, these variations mean nothing. But one of your requirements is that the longest round must still fit the mags. And your rounds are long enough that one could hang up in the mag, so seat deeper.

Buy a box of round nose FMJ, and try those to see if you get variation in COAL. If you don't, you will know the issue was with the bullets.

For the ones you have now, turn your seater stem in a half rev. That should do it.
 
ok. found the problem. It's the freaking cheap caliper! This is the 2nd day I use it since I bought it back in June. the number will jump random off by, sometimes huge numbers, some time small even after reset zero.
once I use the wolf ammo as reference as fixed the measurement, instead of reading the actual number from LCD, most of the cartridges are actually good, either 1.235" or 1.236" which is well within limit and what I expected from the machine and all the settings I did. now I do have to pull 6 out of 20 which were the ones I did at the very beginning to setup the dies as they are too short. Man... Talking about attention to details.

And Ganderite's suggestion(buy a box of ball ammo) also reminded me to check more of my wolf reloaded ammo which is the only ammo I have been using and do trust. After opening 2 boxes of the wolf and measure them, they do have also slight different in OALs, maybe 2-3 thousandth, can't tell for sure because of the crappy caliper, but with the same fitting test, one is definitely different than another. so, I think as Ganderite and other explained earlier, slight different in OAL is ok as long as they fit the barrels and mags well. Thanks everyone for the input. I am one big step closer to the field test.

now I need a new caliper. any suggestions? I read igaging is good, but couldn't find the absolute origin version online in Canada. Mitutoyo is too expensive for me.
 
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now I need a new caliper. any suggestions? I read igaging is good, but couldn't find the absolute origin version online in Canada. Mitutoyo is too expensive for me.

I've had good luck with the cheap dial caliper I bought years ago. It checks just fine against the 1.000" standard that came with the 1-2" Starrett micrometer I have. Chinese import, but no battery to run down or any electronics to drift.
BTW, I also have a cheap electronic caliper that I use occasionally. I guess I lucked out with the Princess Auto version....
 
Luckey, I've got a couple of sets of the cheap digital calipers which I almost never use. For me it's the rate that they eat batteries. It seems like every time I use them they are dead. And now it seems like you're finding that the one at least is also flighty as blazes.

I do a lot of home metal machining. I've bought and used mechanical dial calipers from back when THEY were the "cheap import". Oddly enough I've found that they keep registering spot on when I happen to try them on a 1 inch standard from a Mitutoyo micrometer set about once ever couple of years. So my advice is to pay a little more and buy one of the non electrical dial calipers. They are barely any harder to use than the digitals and only cost about $10 more for a 0-6" version.

Just treat them well by keeping them clean and don't put them where heavy things can fall on them or drop them on the floor. The one set I ever ruined out of the half dozen I own got tipped onto the floor where it broke. The others I have when tested and compared always test out to within a needle's width of 1" when tested on the micrometer standard and test to within a quarter thou on some other odd sizes out to 4 inches the couple of times I've checked in the 30 years I've owned them. And we're talking about the basic dial calipers that I see Busy Bee Tools selling at $28. Cheap as they are these import calipers are my "go to" measuring tool over the couple of digital calipers I bothered to buy.

In fact the only time I put the battery into the one digital caliper I use is when I need to do some metric measurements and I don't want to bother with conversions.
 
since the same advice from two gurus, I guess my next one will be a dial then. no battery to worry. which brand are you guys using now? I may just go get the same.
every time I listen to you guys, things just move so much fast for me. Thanks!
 
I hesitantly bought my first cheap asian import pair about 30 years ago. After testing them and using them a while I added another half dozen over the next ten years buying the cheap Chinese models sold by Busy Bee, KMS and similar cheap import tool outfits. I only bought one more about 15 years ago to replace the one that got flicked off onto the floor.

As I said above whenever I test them against decent standards and against each other they have always agreed to within a quarter thou at most at any point along the whole range. And they always agree on the 1" standard from my 1-2" Mitutoyo micrometer to within a needle's width at most on the worst of them. And near as I can tell that's within about two tenths of a thou. Good enough for day to day stuff in my books.... :d

Try to find a place to hang them up or at least to set them aside so they aren't sitting in with the bench clutter and grit. Those things will kill any mechanical measuring tool such as a set of calipers. But you don't need to go all OCD to protect them either. Just some good common sense will do. And while it may seem simple don't zip them open and closed rapidly. No point in putting excess wear on the internal gearing and rack attached to the bar. A good speed is one which would see the carriage go end to end in around 2 seconds. for smaller movements figure on a suitable portion of that same 2 seconds. That's how I've treated mine and here I am 25 to 30 years later still using them with great reliability.
 
All great advices and experiences. I am so happy I am on this site and found you guys! good night!
cranked up another 40 test rounds with two different loads(HS-6 with 7.2 and 7.6) in 3 hours tonight(yeah, I've been extremely careful). tomorrow I will try to get the 7.4 and 8.0 done. Then head for the range. anticipation and anxiety at the same time. Reloading virgin. lol..

I hesitantly bought my first cheap asian import pair about 30 years ago. After testing them and using them a while I added another half dozen over the next ten years buying the cheap Chinese models sold by Busy Bee, KMS and similar cheap import tool outfits. I only bought one more about 15 years ago to replace the one that got flicked off onto the floor.

As I said above whenever I test them against decent standards and against each other they have always agreed to within a quarter thou at most at any point along the whole range. And they always agree on the 1" standard from my 1-2" Mitutoyo micrometer to within a needle's width at most on the worst of them. And near as I can tell that's within about two tenths of a thou. Good enough for day to day stuff in my books.... :d

Try to find a place to hang them up or at least to set them aside so they aren't sitting in with the bench clutter and grit. Those things will kill any mechanical measuring tool such as a set of calipers. But you don't need to go all OCD to protect them either. Just some good common sense will do. And while it may seem simple don't zip them open and closed rapidly. No point in putting excess wear on the internal gearing and rack attached to the bar. A good speed is one which would see the carriage go end to end in around 2 seconds. for smaller movements figure on a suitable portion of that same 2 seconds. That's how I've treated mine and here I am 25 to 30 years later still using them with great reliability.
 
ok. I got the dial caliper from the toronto company I found on amazon: http://www.amazon.ca/Accusize-0-02mm...l+caliper+dual
it's good to support local business when you can. It runs very good. thanks again for the good advice. this is a keeper. now I can easily get consistent and accurate readings.

However, the OAL issue is a little bit more complicated than I thought. When using the new caliper to measure all the 60 cartridges I loaded, I found two set of OALs, 1.235" and 1.240". further investigation reveals that all the 1.235" is from my single stage operations. Basically, I do one step at a time only using one out of the 4 stations on Dillon to make sure my basics are right. Then once I started to using progressive, the seating station starts output 1.240". Purely based on my observation, it might be because there are physical resistances from other stations. This means I either have to use more force, which can't go very far because everything is to the limit and also risk to force a mis-aligned the primer from time to time(another rare problem, maybe to do with the brass retention spring adjustment), or I have to adjust seating die settings when using single stage mode vs progressive mode?

could you please advise? Thanks! Dillon helpdesk offers no help this time and said "don't worry about the 5 thousandth of an inch". Well.. I guess they are not all that good as people says.
 
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.....it might be because there are physical resistances from other stations.....

BINGO! I've found the same thing happens. There's always going to be some flex in the shell plate and die head which will make the final OAL creep a little once you switch from one round at a time through the stations to filling them all up. But .005 isn't the end of the world. When I see the slight growth I just tweak it out over a few rounds done progressively. Unless you're really nudging the limit on what will plunk test in your chamber it'll be OK having a few that are that much extra.

You'll find that if you're running cast bullets at some point the wax lube and little grains of lead build up in the seating die and cause the OAL to creep a little shorter over a few hundred rounds. I find I need to stop and clean the seating die when loading cast bullets about ever 900 to 1000 rounds. If I don't it gets pretty gunked up in there.
 
Did I mention I am the over paranoid type? :p

I guess it's my wishful thinking that I could use 550b as single and progress just like that. well, at least I know why. It's a good experiment.

yes. I should be happy I am getting very consistent results now. I even pull some of the wolf reload I got to see how the bullet seating compares to mine. everything looks good so far. I will adjust the seating accordingly once I am more familiar with the motion of progressive. I am happy with the slow, controlled pace so far. 550B is indeed a great machine! thanks again!

BINGO! I've found the same thing happens. There's always going to be some flex in the shell plate and die head which will make the final OAL creep a little once you switch from one round at a time through the stations to filling them all up. But .005 isn't the end of the world. When I see the slight growth I just tweak it out over a few rounds done progressively. Unless you're really nudging the limit on what will plunk test in your chamber it'll be OK having a few that are that much extra.

You'll find that if you're running cast bullets at some point the wax lube and little grains of lead build up in the seating die and cause the OAL to creep a little shorter over a few hundred rounds. I find I need to stop and clean the seating die when loading cast bullets about ever 900 to 1000 rounds. If I don't it gets pretty gunked up in there.
 
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