I started seeing high variance in COAL with a new lot of Precision Delta FMJs

[paltrypoultry]

I'm loading 9mm on a Lee Loadmaster.  I got 1k 9mm 147gn FMJs from Precision Delta back in October 2020, and loaded them all.  I saw very consistent OALs (using single headstamp brass).  Nearly all rounds were within +- .002" and most were within +- .001"

 

I liked them so much that I ordered another 3k, in February 2021.  When I ran out of the first lot and switched to this new lot, I immediately saw my OALs start jumping around, by a lot (same brass, press, and everything else).  I'm targeting 1.140" and I see as low as 1.132" and as high as 1.146" at the extremes, but anything between 1.135" and 1.145" is common.  1.132" is almost low enough that I wonder if I should redo load dev.  1.146" is *almost* long enough that I might start worrying about my CZ's really short freebore.  A lot of variance that I wasn't seeing before.

 

I thought maybe something had loosened up on my press, since I did originally have to do some work to get the press making consistent OALs.  But I did a run with a couple hundred Berry's and found OALs all within +- .002".  I also find that with these PDs, I can seat and reseat a round as much as I want, and COAL will never get even .001" shorter, which I think points to it not being the press.

 

I picked a long and short round from a run today and took some measurements to try to learn more.  My main takeaway is that the variation seems to be between the ogive and the tip.  The bullet in the shorter round has a more 'blunt' profile -- you can even see the difference with the naked eye.  There's little-to-no difference in CBTO, nor in bullet base to ogive (though see my note on ogive below), and very little difference in weight.  Based on that, I want to conclude that I don't need to worry about pressure with the short rounds, since the case volume should be nearly identical despite the OAL being so different, and I don't need to worry about hitting the rifling either since CBTO is very close.

 

Questions: has anyone else noticed a recent big jump in OAL variance with PD 147 FMJs?  Which one is 'normal' for them: the consistent batch in October or the high variance batch in February?  Given that I *think* the short ones should be the same as the long ones pressure-wise, and freebore-wise, is there anything else to worry about?  Accuracy?  Other thoughts?  Should I just stop checking COAL and check CBTO instead?

 

Pics of comparisons below:

 

Long boi:

 

https://i.imgur.com/vm5m0JE.jpeg

 

Short boi:

 

https://i.imgur.com/cSrFFCb.jpeg

 

Case bottom to 'ogive' is about the same (not sure if it's truly ogive for these .355 bullets or not -- it's a '.358' comparator)

 

https://i.imgur.com/10sjAVJ.jpeg

https://i.imgur.com/DXu2ttH.jpeg

 

Side by side, if you look carefully, you can see that one is shorter, and that the longer one has a 'pointier' profile:

 

https://i.imgur.com/bpQ3ql6.jpeg

 

The difference in profiles is also visible from above:

 

https://i.imgur.com/7NYWnFl.jpeg

 

I pulled the bullets.  The long one is, unsurprisingly, longer:

 

https://i.imgur.com/9v1Zq43.jpeg

https://i.imgur.com/0rMGHOo.jpeg

 

Though, only .005-.006" longer, not the .009-.010" difference I saw in OAL.

 

Bullet bottom to ogive is the same:

 

https://i.imgur.com/UHAB81w.jpeg

https://i.imgur.com/KGjO4QH.jpeg

 

For these 'ogive' measurements, I could get a pretty wide range of readings depending on how I worked the bullet and calipers around.  So for each, I used the shortest reading I was able to get after messing around with it a bit.

 

The longer bullet is .1gn heavier (147.4gn vs. 147.3gn)

 

[Boomstick303]

I am seeing some rather strange OAL differences in the 2000 rounds of 124 gr JHP Precision Delta’s I just loaded. I have not pegged what is going on in that I have just noted the variance tonight. I will have to dig a bit to see if the same thing is going on with the 124gr. 

Edited June 1, 2021 by Boomstick303

[Farmer]

Not on PD’s but on many of the blems that I’ve bought over the years I’d say 99% had varying ogives. Had picked up some RMR 124 JHP blems that were like that and had to sort them into 3 batches. I made an insert for my Hornady OAL gauge that matches my bbl for size so that sped things up. Kinda thinking maybe they are pushing a bit too hard and getting sloppy. Are you using a flat top punch or one that fits the bullet nose?

[paltrypoultry]

13 minutes ago, Farmer said:

Not on PD’s but on many of the blems that I’ve bought over the years I’d say 99% had varying ogives. Had picked up some RMR 124 JHP blems that were like that and had to sort them into 3 batches. I made an insert for my Hornady OAL gauge that matches my bbl for size so that sped things up. Kinda thinking maybe they are pushing a bit too hard and getting sloppy. Are you using a flat top punch or one that fits the bullet nose?

 

For me with these PDs, both lots are full price non-blems.  By punch do you mean the seating stem?  I'm too lazy to remove it, but I'm pretty sure it's cupped, not flat.  Though I'm not sure which part(s) of it contact the bullet.  It's a Lee seat+crimp die.

[Cuz]

Interesting.  I just bought a bunch of Precision Delta 124gr JHP.  I've never used their products before.

However, I will say that I've been loading Berry's, Black Bullets Int., Blue Bullets, and Bayou bullets, all in 9mm with mixed brass on a Dillon 550 press, and I've always gotten a wide spread when measuring OAL.  I've always considered a spread of +/- 0.005 to be somewhat "normal" with mixed range brass.

 

 

[Farmer]

12 hours ago, paltrypoultry said:

 

For me with these PDs, both lots are full price non-blems.  By punch do you mean the seating stem?  I'm too lazy to remove it, but I'm pretty sure it's cupped, not flat.  Though I'm not sure which part(s) of it contact the bullet.  It's a Lee seat+crimp die.

Yes, sorry I meant seating stem. Most of the Lee’s are rounded. I re-read your thread and caught the part of the ogives being the same. On the ones I had there was anywhere from .010 to .040 variation but the comparator I made was .355. The noses on yours could be longer but that doesn’t explain why they don’t or won’t seat deeper, unless it’s compressing the powder. Is there the same amount in the case with both long and short? Do the long ones plunk ok?

Edited June 1, 2021 by Farmer

[paltrypoultry]

8 hours ago, Cuz said:

II've always considered a spread of +/- 0.005 to be somewhat "normal" with mixed range brass.

 

 

This is all Blazer brass.

 

3 hours ago, Farmer said:

Yes, sorry I meant seating stem. Most of the Lee’s are rounded. I re-read your thread and caught the part of the ogives being the same. On the ones I had there was anywhere from .010 to .040 variation but the comparator I made was .355. The noses on yours could be longer but that doesn’t explain why they don’t or won’t seat deeper, unless it’s compressing the powder. Is there the same amount in the case with both long and short? Do the long ones plunk ok?

 

It's definitely not compressing powder since I'm using 3.3gn of titegroup, but yeah, same amount anyway.  My theory is that since seater is cupped, it isn't engaging the bullet at the tip but rather somewhere along the curve, and that the difference in COAL comes from the difference between that ring and the tip.  The long ones do plunk ok still but I suspect they might fail a sharpie test, based on the measurements I took during my original load dev for this bullet. EDIT: actually, thinking about it more, they might pass a sharpie test still too, based on the ogive measurements not being very different.

 

I checked a few more loaded rounds from the run of 200 I did yesterday.  I found a 1.134" and a 1.149".  I took a 1.140" and put it in the comparator and zeroed it.  The 1.134" was also 0.000".  The 1.149" was 0.003"

Edited June 1, 2021 by paltrypoultry

[missed it by that much]

I've used 124 hollow points before with good results. Just ordered 2000 more. Hopefully they're good as well. Nervous now 

[MemphisMechanic]

Go shoot them to see how they group.

 

All coated bullets and most plated do this through my 650 and 1050; the die seats using the ogive and you measure to the bullet tip, so tolerances in bullet profile and case neck tension stack quickly.

 

But ammo with an OAL variation of .008” - .010” would often have a standard deviation of six or less in it’s velocity, and shoot a crazy tight group.

 

I’ve learned not to rely on OAL too much. As long as it feeds.

[Farmer]

10 hours ago, paltrypoultry said:

 

This is all Blazer brass.

 

 

It's definitely not compressing powder since I'm using 3.3gn of titegroup, but yeah, same amount anyway.  My theory is that since seater is cupped, it isn't engaging the bullet at the tip but rather somewhere along the curve, and that the difference in COAL comes from the difference between that ring and the tip.  The long ones do plunk ok still but I suspect they might fail a sharpie test, based on the measurements I took during my original load dev for this bullet. EDIT: actually, thinking about it more, they might pass a sharpie test still too, based on the ogive measurements not being very different.

 

I checked a few more loaded rounds from the run of 200 I did yesterday.  I found a 1.134" and a 1.149".  I took a 1.140" and put it in the comparator and zeroed it.  The 1.134" was also 0.000".  The 1.149" was 0.003"

Like MM posted, go shoot some and see how they work. The Lee seater I have has a pretty open round nose and pretty much pushes on the nose. Only other thing I have thought of is if there’s some crud in the die binding up the floating seater and crimping plug on some loads. You would have to pull the die apart and check, no real biggie. 

[paltrypoultry]

Yeah I'm curious how they group. I have been shooting them at matches and missing about as much as normal I guess.  It's too bad I shot up the consistent lot already so I don't really have a comparison for a grouping test.  I'm pretty sure at this point based on all the data and experiments that the variance is coming from the bullets' profile and not the equipment.

[Cuz]

I got a chance to hit the range yesterday to test a quick load of the Precision Delta’s 124gr JHP against my standard Berry’s 124gr RN load and two other brands of coated Bullets. Mind you, I’m not a great shooter, so for me a good group is having all shots at least touching a single white paster at 35 ft.  The PD was easily the best group, followed closely by the berry’s. The group size from the coated Bullets was twice the size of the PD groups. It’s very possible I just don’t know how to wring out better accuracy from a coated bullet, and unless I can figure it out, I’ll use the ones I have as practice ammo and stick exclusively to Precision Delta if I can continue to get them. 
 

[RGA]

FWIW, If the manufacturer makes several runs of the same type of (fmj) bullets using different pointing/ogive forming dies in the swaging process you will probably see some variance in the ogives. No 2 pointing/ogive forming dies are exactly the same.

 

In the case of pointing up JHP bullets different jacket dimensions (length of the cup) can cause some length variation in the finished product as well.

[Sigarmsp226]

Well this thread caught my attention because I received my first order from Precision Delta last week for 2000 pieces of their 124gr JHP so I opened one of the two boxes I received and pulled 25 random bullets from the closed bag. 
 

I will let the pictures below show you the range associated within the 25 rounds I measured. Needless to say I was surprised by this spread. Guess my future orders will not be with PD for this specific bullet or their 124gr FMJ bullet.  I would have thought that this specific bullet would have had a tighter manufacturing tolerance  than this - but what do I know….. 

 

 

 

 

Edited June 2, 2021 by Sigarmsp226

[Cuz]

1 hour ago, Sigarmsp226 said:

Well this thread caught my attention because I received my first order from Precision Delta last week for 2000 pieces of their 124gr JHP so I opened one of the two boxes I received and pulled 25 random bullets from the closed bag. 
 

I will let the pictures below show you the range associated within the 25 rounds I measured. Needless to say I was surprised by this spread. Guess my future orders will not be with PD for this specific bullet or their 124gr FMJ bullet.  I would have thought that this specific bullet would have had a tighter manufacturing tolerance  than this - but what do I know….. 

 

 

 

 

Thank you Sigarms, 

one less person I will have to wrestle with to try and claim the limited amount of bullets available from PD. 
do you really think that 0.011” is that big a deal???

what other bullets are you using?  I have found incredible variances in size and weight among 4 different coated bullet manufacturers. This is handgun ammunition, not precision rifle shooting. Have you loaded up a bunch without regard for OAL variance and shot them?  
I just “discovered” PD Bullets for the first time last week and am very glad I did. They group better than any other bullet I’ve tried, but they are also the only jacketed bullet I’ve tried in many years. They were also fairly stable over the chronograph, but I use mixed range brass so I expect some variance. 
I would really like to know what other billets you use and what their tolerances are. 
 

[HOGRIDER]

2 hours ago, Sigarmsp226 said:

Well this thread caught my attention because I received my first order from Precision Delta last week for 2000 pieces of their 124gr JHP so I opened one of the two boxes I received and pulled 25 random bullets from the closed bag. 
 

I will let the pictures below show you the range associated within the 25 rounds I measured. Needless to say I was surprised by this spread. Guess my future orders will not be with PD for this specific bullet or their 124gr FMJ bullet.  I would have thought that this specific bullet would have had a tighter manufacturing tolerance  than this - but what do I know….. 

 

 

 

 

Hey Mark!

 

Your post also caught my attention; so I decided to check a box of Zero 147g JHPs that I had open from a loading session yesterday.  Right now, with my efforts concentrated on a new CZ Shadow 2, I'm very conscious of my finished cartridge OALs since this is my first CZ and it definitely has a shorter chamber that I'm certainly not used to!

 

Anyway, I pulled out 25 bullets from the box and measured each one randomly.  Here's my shortest and longest.

 

IMO, the exposed base may have something to do with PD's variance in bullet length.  But, since I have not loaded/used any PDs, this is only a guess.  I'm also thinking that if your using a quality seating die that seats off the ogive, then this difference in bullet length should not really affect the finished cartridge's final OAL.  Is this a valid point?

 

 

 

[Sigarmsp226]

HogRider - Thanks for your post. I never really thought about this the way you mentioned but you are 100% correct.  This variance should not be reflected to this magnitude on the OAL of a group of loaded rounds.
 

Thanks for sharing this information and your thoughts as I was thinking that this variance could/would require me to rethink my OAL on the rounds I currently load for my X5 and my PPC....I will grab 100 rounds this weekend, measure each bullet and then load the same 100 units to see what the OAL range reflects the same variance range. Based on what you have shared I should not see the same variance range....

 

I will share with you what the results this weekend.....Thanks again my friend...Appreciate you taking time to postmyour thoughts....Mark 

[Sigarmsp226]

Cuz - Honestly it has been years since I have taken time to measure the OAL of any group of unloaded projectiles to determine the variance. You are correct that I used to do this primarily on rifle rounds when I was shooting my precision 308 rifle....  Having read HogRyder and your post I guess it is fair to say that I would not have even taken the time to measure these bullets had this thread not attention having just ordered for the first time from PD....

 

I appreciate your comments and feedback also and sharing your thoughts.....In review I guess I was quick to jump on this threads band wagon with no real finished round evidence that the bullet variance would be reflected in the loaded round OAL...

 

I do pay attention to my OAL on my loaded rounds and will report back on how these load out and more importantly - shoot and group....Thanks for the call out suggesting that I re-think my post....I appreciate you taking the time to share your thoughts. His thread has helped me realize that one variable may NOT have the same affect on a separate variable....Mark

[Cuz]

7 hours ago, Sigarmsp226 said:

Cuz - Honestly it has been years since I have taken time to measure the OAL of any group of unloaded projectiles to determine the variance. You are correct that I used to do this primarily on rifle rounds when I was shooting my precision 308 rifle....  Having read HogRyder and your post I guess it is fair to say that I would not have even taken the time to measure these bullets had this thread not attention having just ordered for the first time from PD....

 

I appreciate your comments and feedback also and sharing your thoughts.....In review I guess I was quick to jump on this threads band wagon with no real finished round evidence that the bullet variance would be reflected in the loaded round OAL...

 

I do pay attention to my OAL on my loaded rounds and will report back on how these load out and more importantly - shoot and group....Thanks for the call out suggesting that I re-think my post....I appreciate you taking the time to share your thoughts. His thread has helped me realize that one variable may NOT have the same affect on a separate variable....Mark

I definitely want to know how you make out at the range. I used to get obsessive about .05 gr differences in the powder charges of loaded rounds to the point of checking the weight every 5-10 rounds. Man, you want to talk about driving yourself insane. And then I went and loaded it all in mixed range brass thus defeating the whole point of checking the charge weights. Sometimes I’m my own worst enemy. The variance in OAL of my loaded ammo used to drive me nuts too. In the end, I let the group sizes and chronograph decide if a load will work and I worry a lot less. Obviously it has to feed reliably as well. Although, as soon as primers become readily available, I will have a LOT of coated Bullets on hand to experiment with to see if I can get the groups to shrink down a bit. I may be over crimping.   But right now I don’t want to “waste” primers to figure it out. I stumbled onto the PD Bullets and have had great results. So, as long as I can continue to get them I will use them exclusively. And I think I will reframe from measuring the OAL of any individual Bullets for now as the may just push my OCD over the edge. 
 

[Superkaratemonkeyfighter]

PD is considered one of the best jacketed bullet makers out there.

I hope you get it  resolved. 
OAL might not be effected but an open shooter might take issue with a extra long bullet compressing the powder that much ore than he expects. 

Edited June 3, 2021 by Superkaratemonkeyfighter

[Underwood]

On 6/1/2021 at 11:11 PM, MemphisMechanic said:

Go shoot them to see how they group.

 

All coated bullets and most plated do this through my 650 and 1050; the die seats using the ogive and you measure to the bullet tip, so tolerances in bullet profile and case neck tension stack quickly.

 

But ammo with an OAL variation of .008” - .010” would often have a standard deviation of six or less in it’s velocity, and shoot a crazy tight group.

 

I’ve learned not to rely on OAL too much. As long as it feeds.

i agree 100% with this 

[Bakerjd]

As a brand new reloader I am now a bit less concerned with OAL on unloaded bullets. I didnt really worry about weight of the bullets to start with. Mostly for me I've loaded coated DG 135gn bullets and pit of the 6k+ I've bought all have been above the 135gn weight. Highest was 135.9 I belive.  I've weighed about 20. 

 

I have a bunch of zero and armscore jacketed (I think that's what it's called, they look like the PD ones) I want to save for my new open gun I'm getting in a few weeks. 

[Sigarmsp226]

Cuz and HogRider et al: - I was not able to get into the reloading room this past weekend as planned.  My son had some unplanned work come up and my DIL was already scheduled to work so Ms. Sigarmsp226 and I took the lead role on house, dog, cat, and most importantly grand-daughter sitting (all three are girls - ages 2, 4.5, and 6) and because they live 2.5 hrs away I could not "sneak" home to load a few rounds.....So Friday evening and all day Saturday and Sunday was filled with concrete chalk pictures, water color painting, and lots of quality Paw-Paw time (I make a mean Mac & Cheese and Pancakes with Sprinkles - not at the same meal).... 

 

I WILL be loading up 100 rounds this week and will provide the OAL details here and I WILL be shooting said rounds this up coming weekend because I co-lead a monthly SCSA Steel Challenge Match at our local gun club.  I will not be shooting these rounds at the steel because I am only shooting rimfire right now due to the primer shortage but have plans on setting up some paper targets in the adjacent bay where we shoot the steel to see how these group on paper.

 

Updates to follow and sorry I was not able to keep my earlier commitment to you guys.  Mark     

[Cuz]

Nice, a weekend with 3 granddaughters at that age must have been a blast.  I certainly hope weekends like that are in my future.  My guys were a lot of fun at that age.  I thought they were expensive back then, but at the rate they go thru ammo, I'm rethinking whether it cost more back then or now.

 

Ok, you have motivated me, so I went and measured about 50 of the 300 rounds I loaded this weekend, and the range was from 1.0835 - 1.0920.  This is pretty much the range of OAL (+/- .005) that I've always gotten across any bullet brand.  This is with plain old mixed range brass so I'm ok with it.  As long as the longest OAL feeds and plunks reliably I just never worried about it.  I am loading on a 25+ year old RL550B press.

 

I see similar spreads when I chrono my ammo, but as long as they all have a PF between 128-132 I just don't worry about it.  I've only shot  1 match in my entire life that had a chrono stage, but I like to always follow the rules and I'm confident my ammo would pass in my kids Glock 17, my other kids STI, and my Glock 34.  There's a couple of PF difference between them, and the Ruger PCC is in the 140's so that's no problem.

 

You have also motivated me to inquire about powder charges and acceptable ranges, but that's a thread drift, so I'll start a new topic for that.

 

Good luck when you do get to the range, keep us posted.

 

[Darrell]

I measure off the ogive, not the tip when comparing or checking OAL. Measuring all my PD bullets JHP, and FMJ's are within .002" off the ogive which is what will hit the rifling first.