124gr 9mm HBFP bulge issues

L

locknloader

New member
So i have run into my first snafu with reloading and need some guidance.

My first run ever, i did 20 of the following round:

Berry's 115gr Round Nose
3.9gr Tite Group (start load)
OAL 1.150 approx.

Measured EVERYTHING multiple times on each round, tested with a gauge as well as the barrel of the gun i would be shooting, all those rounds fit great.

Now when i went to load up some of these rounds, i had 2 which will not go into the barrel all the way:

Berry's 124gr Hollow Base Flat Point (HBFP)
3.6gr Tite Group (start load)
OAL 1.050


Now there are a few things i notice on this round that are different. The seating depth of the bullet is way more than the round nose, makes sense due to the shape of the bullet and since am seating more into the case that explains the slightly lower powder charge compared to the round nose. I am still within SAAMI spec so not worried about that and don't think its causing issues (i did the plink test with my barrel to figure out where i had to be for OAL and dialed in a hair under that)

I measured the cases where the bullet is seated and i am right at the max SAAMI spec of .3800 for the width where the bullet is seated in the case, but they still do not fit into the barrel.

The only thing i can think of are irregular bullets or is it possible i seated the bullet on an angle? My flare die is set very "light" and the bullet just barely sits in the tip (i was told to do this to extend case life). Could this be causing some rounds to go in crooked and push the case out around the top?
 
I shoot a ton of both Berry's and Extreme bullets in 9mm, and as a final step after seating crimp with the Lee Factory Crimp Die. I know that for normal cast this is a no no, but works well for me with the copper plated bullets. I do seat and crimp separately, and sometimes there may still be a slight bulge but it neither affects reliability or accuracy in my experience.
 
Locknloader,

You are most likely seated too deeply. All the rimless automatic pistol rounds have a limited depth to which you can seat bullets in the case, after which the brass wall gets thicker in order to prevent an unsupported style chamber from allowing the brass to blow out. When you push bullets into that thicker location, the brass over the bullet bass is expanded wider than the chamber.

Below is the example of the .45 Auto. You can't seat deeper than about 0.35 inches into a typical .45 Auto case. I don't run 9 mm, so I can't drop a pin gauge into a handy case to give you the number for it, but it will have one. Also, seating too deeply raises pressure considerably, so you don't want to go too deep for that reason, either.

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I'm almost, not quite with Unclenick.

As i have run into this with 9mm, i would suggest that you expand the case mouth slightly greater than with the 115gr. You probably have the bullet getting slighly cocked upon seating.

Also ran into this with 180gr in 40 S&W.
 
(i did the plink test with my barrel to figure out where i had to be for OAL and dialed in a hair under that)
Click to expand...

It is possible that your COL is on the ragged edge of plunking. Have you compared actual COLs of the bad rounds vs the good ones? Also, have you tried seating the bad rounds a couple of thousandths deeper and see if they plunk?
 
Good info UncleNick. I know what your saying but hadn't considered that aspect for my method of determining COL. I may have to pull a few rounds down and investigate this. I've always assumed, and IME found it to work, that as long as I work my loads up after determining seating depth that I would be fine if I don't wind up with a compressed load in 9mm. I am curious if the bullets are getting swaged enough to affect accuracy, or I just can't tell due to the relatively short ranges I shoot pistols at, basically 7-15 yds. Since I shoot almost exclusively copper coated maybe the swaging is masked because I don't experience any leading, but it is happening and could possibly account for an occasional flyer, not always my lack of accuracy.
 
locknloader, I have been loading that same Berry's bullet. While making up a dummy test reference round I found with my 2 guns I could seat these out to 1.065" and they would cycle and feed just fine. Though I am loading them at 1.060". I doubt that .010" shorter would make a bit of difference as to whether they would cycle or not.

Now when I 1st started loading these I only had one 9mm to load for until my wife bought hers. With her XD Mod2 these rounds , half wouldn't chamber. After a little investigating I found I was using a very light crimp for my gun. I turned the seating/crimp die down about 1/8 - 1/4 turn and everything was just perfect. I do not have the 4th FCD in my set.
 
You started out with a round nose bullet and now are using a flat nosed bullet, did you change the plunger in the seating die from round to flat nose configuration. If you bought RCBS dies you would have gotten two different stems for in the seating die. Look up in the seating die you have to see if the stem has a round profile or a flat one. If it is round and you are using flat nosed bullets the bullets could be seated crooked creating a bulge on one side of the case.

If this is the case all the care in the world won't correct getting a bulge once in a while.

This may or may not be your problem but you need to check your seating die to see what profile you are using. It has to correspond to the bullet profile you are using.

Just something else you need to check.
 
LE-28 - I think you solved it... my stupid self did not change out the pin inside the seating die!!! That must have caused the crooked seating. I might load some more up today will let you know know if that takes care of things.
 
Stems

How bizarre. I have never changed the stem in my seating die, regardless of which bullets I used.

It sounded like your OAL is too short and you are bulging the side of the brass a little bit. The other option could be that the resize die is not adjusted all the way to touching the shell plate and you resized some brass fired from a Glock.


Dan...
PS. I load all my 115 gr to a oal of 1.130, 1.050 sounds real short.
 
I too have never changed a stem in my Lee dies and I have loaded both Berry's RN and their Hollow Base Flat Point Thick Plated (HBFPTB) in the same dies w/o any incident.

Also the Berry's Flat Point is to be seated to that length because if it's shape. If it was seated to 1.130" there would be hardly any bullet inside the case.
 
I had used a Lee FCD for 9mm for 10's of thousands of rounds without issue. Loading 147gr FP with lube groove to 1.10" or so the bullets are seated pretty far into the case. CBC brass proved to be a real problem. When a .356" bullet is seated deep in a 9mm case the bullet is swaged at the base and the CBC brass was actually "springing" back leaving the bullet very, very loose and the occasional round that wouldn't chamber.

I mostly load 115gr Acme (RN) and am not currently using the FCD so the CBC brass doesn't really present a problem, but definitely something to think about when loading the longer bullets short.
 
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