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

[lll Otto lll]

 I received an order from PD last week, same bullet as yours.  Base to ogive is within 1 thousandths.  That's plenty good for me.
I'd bet 1 thou is less variance than the wall thickness of the brass you're loading. 

Edited June 8, 2021 by lll Otto lll

[Bowman]

I've been loading 124 grain PD's for years and they have always been accurate although the loaded rounds do show some OAL variation.  I got some 147's recently and I'll have to check and see if they show more variation than the 124's I've always used.

[ChemistShooter]

I had a problem like this with Bayou Bullets coated once.

 

I'm pretty certain the problem was an uneven coating on the bullets. Either a bad batch or quality control being tossed out the window.

 

I initially thought it was me, of course. i went around and around and around trying to figure why my COALs were suddenly varying so much. Eventually I started wondering about the bullets. I got a test batch from another supplier, don't remember who. (Been months since I've been able to reload.)

And damn, that was it. I proved it by making a test run alternating bullets on the same run. The Bayou Bullets varied all over the place. The other supplier was nice and tight.

I noted the Bayou Bullets had a rough-feeling coating, whereas the other supplier's coating was shiny-smooth.

[paltrypoultry]

I grouped them and they're about the same as the first batch that didn't have the high variance, maybe a little better.  Measuring CBTO on a few dozen rounds with the biggest COAL spread from my last reloading session, the CBTOs were all within +- .002 even when COALs were +- .006.  Except one outlier that was short both on COAL and also on CBTO (.006 short).

 

So I don't think the variance matters for reliability or accuracy.  The only downside is that I had been using the Armanov case gauge / COAL checker which lets me really quickly find a round that's too long or short.  But with this batch of bullets, lots of them look a bit off in the COAL checker, so either I stop checking and then maybe a truly long or short round gets through, or I have to check CBTO on all the ones that look off in the OAL checker, which is a lot of them.

[paltrypoultry]

I just opened the 3rd and last box from the order where I started seeing the wandering COALs.  The COALs are still all over the place, but now I'm seeing these, too:

 

 

Those three were from the first 100 I grabbed. That's not normal, right?

[AHI]

I would contact Precision Delta. and not be complaining on a forum.

Edited July 27, 2021 by AHI

[paltrypoultry]

15 hours ago, AHI said:

I would contact Precision Delta. and not be complaining on a forum.

 

I did.  They replied today saying they had a known issue around that time and that they'll be in touch to have me send them back the bullets I have for replacements.  Sorry you think I'm complaining; I'm sharing and soliciting info with other customers.

[Ssanders224]

Just ran across this thread. There's been good information given, but I'll add to it. 

 

- The nominal length for PD 147 FMJ is ~.682".  Normally speaking, inside of a single lot#, tolerances will not be more than +/- .001. However, lot to lot (and machine to machine), finished length can vary from .679" to .686". This is due to tolerance stacking across materials and other intermediate processes, and is usually a function of achieving an exact weight.  This is the reason, for example, that you see lot # & machine # on products like Hornady 55gr FMJ-BT projectiles. There WILL be minor dimensional differences as materials, machine setup, and tooling changes. 

 

- That said, PD has processes in place to insure customers do not receive mixed lots within single orders. This is why I implore not only PD customers, but customers of other jacketed projectile companies to order larger quantities at one time if they are very particular about dimensional specifics other than weight and dia.  (The caveat being that   single lots can not be guaranteed on large ~50k+ type orders). 

 

- Forming tooling, responsible for the profile of the projectile, is made to extremely exacting standards, but ogives can still vary slightly due to a number of other factors. Obviously, significant changes in ogive that will affect loading practices are not accepted. PD is unlike some other projectile companies in that a large portion of the projectiles manufactured are used in-house. Some of our ammunition assembly operators have been loading ammunition for PD for over 35 years. They are extremely picky about the projectiles they use, and they keep the projectile dept. on their toes!  

 

- The issue Paltry Poultry experienced with the defective jackets was part of a small, isolated tooling issue that was detected within the process. Unfortunately it looks like a few thousand made it through. He contacted PD this week, and we're getting him fixed up. 

   

Anytime anyone experiences issues with a PD product, always reach out by email at info@precisiondelta.com, by phone at 662-756-2810, and/or I try to make myself as available as possible here and on other popular platforms. A customer service rep will always assist and get you taken care of with as little hassle to the customer as possible. We truly strive to provide exceptional customer service. 

Edited July 28, 2021 by Ssanders224

[paltrypoultry]

Thanks for the info Ssanders!  I just got off the phone with Lisa who was great, and is gonna hook me up with some replacements.  If the replacements are like the first batch I got from you in October, I'll definitely be happy to keep buying bigger batches from you.

[Farmer]

If I saw those coming out of my press,  I would think I normally had a seating stem problem.