COL Variation

otter25

Beginner
May 22, 2012
131
2
I'm loading 9mm Lugar using Hornady Custom dies and Rainier 115gr HP.I've trimmed all cases to .745 and trying to set COL at 1.150. Loaded rounds are coming out anywhere between 1.148 to 1.153. When I lower the round out of the seater/crimper the seater stem seems to be griping the bullet a bit as there is a slight resistance and popping noise as it lets go. Would it help to lube the inside of the seater stem
 
look inside the die to be sure it's clean . I load a lot of cast lead bullets , and I'm surprised how much lead gets packed in the seating die . another thing it could be the seating stem does not match the bullet profile , causing it to grip , or dig into the bullet . hornady does make different seating stems for rifle dies to match different bullets . maybe they offer them for pistol dies too . I have a set of hornady 300 wby dies that will pull a AccuBond bullet completely back out of the case using the seating stem it came with .
 
+1 on what Jim says about cleaning the die and pulling the stem to see how the bullet matches the inside profile. I also load a lot of cast lead bullets in various calibers and have experienced the same thing and also when loading jacketed bullets. I use Dillon presses and dies for pistol bullets and have modified the seater stem to match the profile of the bullet sometimes just chamfering the stem mouth will do. Most seater stems are designed to seat off the nose I prefer the ogave for jacketed and off the shoulder for cast. Seating off the nose will give you varying COL.
 
This is the first pistol round I've loaded for and its plinking/practice ammo. With that said, dose this +/_ .003 variation really matter? Seems like I read somewhere that seating depth in some rounds can have major effect on pressure.
 
otter25":23j6643w said:
This is the first pistol round I've loaded for and its plinking/practice ammo. With that said, dose this +/_ .003 variation really matter? Seems like I read somewhere that seating depth in some rounds can have major effect on pressure.




I would not worry over that little tolerance in COAL with pistol ammo .
 
I would not be the least bit concerned with a small variation in OAL, but I would highly recommend the acquisition of another seating die so that you can seat and crimp in separate operations. Seating and crimping at the same time just doesn't make a lot of sense once you get past the convenience aspect of it...and especially with cast bullets.
 
And now that I've read what I just posted, I would qualify that by saying that I only use one bullet per caliber/cartridge. Once I set up my dies I lock 'em down and do not adjust again.
 
Seat and crimp in separate operations. Check for seating stem fit to bullet nose. Determine how far down the case the taper crimp is going. you don't need to go past the base of the bullet. Rick.
 
otter25":3tgr7vt0 said:
I'm loading 9mm Lugar using Hornady Custom dies and Rainier 115gr HP.I've trimmed all cases to .745 and trying to set COL at 1.150. Loaded rounds are coming out anywhere between 1.148 to 1.153. When I lower the round out of the seater/crimper the seater stem seems to be griping the bullet a bit as there is a slight resistance and popping noise as it lets go. Would it help to lube the inside of the seater stem

While you did trim your brass (many/most don't trim 9 brass), varying headstamps can/will cause slight diff's in COAL's.....as will sharp edges caused by trimming being run with othes that didn't touch the trimmer. If you have mixed headstamps, this is part of it.

I also seat and crimp in two separate steps. Personal pref ... I find it easier to set up this way, and easier to deal with slight brass legnth variations from one headstamp to the next.....because I don't trim 9.

Lastly .... and really the reason I am chiming in.....another possibility that may or many not apply to you......if you are belling the case a little, but not quite enough ... it can lead to coal variance because it makes it more difficult to insure they are all getting started centered and the same. If the bullet won't sit on the case, or some do - but others want to tip over, increase the bell just a touch....it'll help make coals consistent. If you already know you have enough bell....never mind.

If you aren't loading hot, your stated variances shouldn't matter .... but definitely worth improving.
 
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