Seating depth with PC boolits

[Manns50]

Fairly new to powder coating but I perfected a process for me. I have loaded and shot some PC 40's about 4 to 5 months ago and I didn't change my seating depth I don't believe. Will check the batch I have loaded up but my question is about some 10mm that I'm setting up dies for. Was aiming for the 1.25" OAL for a 200g semi wadcutter. But after achieving that, the bullet is seated too deep in my opinion. Which had me wondering if anyone changes their OAL after PC?
I will naturally experiment and gradually progress to be safe but PC thickness I would imagine vary depending on the coat of course. Just wanted to get thoughts or opinions.

[stubshaft]

The thickness of the PC coating is not going to affect the pressure at all!

[Manns50]

Thanks for the reply, I think I looked into this before and arrived at the same conclusion. Not sure why the bullet had to seat pass the top groove in order to hit the 1.25. Going to experiment with it more today. Using a Dillon die and opted for the smaller seating insert. As it seemed a better fit but was contacting the taper of the bullett and not the flat part of the nose. I may flip the insert around and have it contact just the flat part of the nose.

[gwpercle]

Don't get all hung up on a OAL number .
Powder coating usually adds to the diameter and to the ogive ... the ammo must pass the plunk test .
If the powder coated boolit has to be seated deeper to pass the test ... seat it deeper .
When changing boolits , incuding the use of a powder coated boolit ... seat it where it needs to be ... it must fit magazine , feed from magazine into chamber and it must easily Extract without leaving the boolit stuck in the throat .
Load some dummy rounds for testing ... if there is a hang up ... adjust seating depth untill it cycles .
After determining what your OAL is adjust powder charge .

You can Set the OAL number ... don't read a Book OAL number and think ... I must use this number and nothing else ... you don't .
Seating a boolit slightly deeper will NOT skyrocket pressures .
Gary

[Manns50]

Ok thanks for the tips. Makes sense. This is 1.264 OAL and I have not put a crimp on it yet but is right at the top groove.

[Manns50]

You can also see where the seating die contacts rather than the flat part, which is not a big deal. May go with this and confirm that it chambers. Using a KKM barrel so the chamber is not as loose as the Glock but shouldn't be an issue.

[Kenstone]

You can also see where the seating die contacts rather than the flat part, which is not a big deal. May go with this and confirm that it chambers. Using a KKM barrel so the chamber is not as loose as the Glock but shouldn't be an issue.

Do the bullets measure a consistent diameter AFTER powder coating?

If not, you might want to consider pushing the COATED bullets thru a sizing die after coating/before loading.
I buy coated bullets and always qualify them via a sizing die as the coating thickness may vary, as well as the bullet diameter cast in different cavities.
I don't bother measuring them but I can tell by the varying pressure required when sizing, that they are different diameters.
So, there's that...
If you are already doing this, nevermind, :neutral:
If you size before coating, consider changing to sizing AFTER coating.
jmo,
.

[cwlongshot]

Your coating on the bullets can be adjusted to be thin or think by choosing different powders and by sifting off longer before baking.

A heavy thick coating might be what many want to see but as your finding out, it causes other issues. BESIDES not bening necessary.

[Manns50]

I did size these before and after coating and they are dead on .401/.4015 with powder coat with a very very slight variation. This rubs mold drops some of the best I've ever made really, especially in that regard. I was impressed. But I'm trying to measure the taper crimp and its kind of hard to do as with the bullet in the case it would really have to squeeze the bullet in order to change dimensions I think. Ive always used the factory crimp die and have one on my .40 setup I may borrow until I can get an extra to have on both. Or just back this Dillon taper crimp up as I believe its too much as is me experimenting trying to see a result. I think they are good to go just need to work on a powder drop now and let some go down the barrel in testing.

[fredj338]

A pc bullet should seat to the dame depth, nothing is really changing. If your bbl throat is tight, it might require 2-3000 deeper but thats nothing.

[Cast10]

My 10mm 180 XTP’s seat to 1.255” - 1.257”
My 10mm Lee 401-175-TC’s seat to 1.244” - 1.245”.
My loads are not hot. I shoot a Glock 20 and a 16” Carbine. Carbine has a tight chamber.