9mm bullet length with 115 lead rn
 

Last night I was going to try to start refilling my supplies after a Saturday shooting my latest 9mm acquisitions - PPS and a CZ 75B. I use a Lee Classic Turret Press. I was going by the Hodgdon data on loads for Lead RN with HP-38 - COL 1.1 (my digital rule had it about 1.17) with about 4.6 grains of powder.
For some reason, something did not feel right so I loaded up magazine with the reloads and started to cycle them. First one jammed. Too much effort to get it to eject and when it did the brass came out, but no bullet.
With just the barrel from my CZ, I dropped in some factory loads to see how they seated and then my reloads. Factory loads would easily seat all the way and come out easily. My reloads did not seat fully.
So, re-adjusted my case resizing die and loaded a bullet (no powder/primer). No difference. Then I modified my bullet seating and finally at about 1.07 inches the bullet behaved normally. I checked my final crimp die adjustment and "resized" about 10 of my reloads. Loaded those in one my mags and they cycled properly. Did the same with my PPS and they cycled properly on this wonderful shooting gun.
Went back and "resized" the rest and spot checked a few for cycling.
Have not had an opportunity to test and did not reload any more until I test.
My question - was my methodology OK or did I do something seriously wrong in resizing my reloads.
As I noob at this (about 1 year), I am needing to learn.

A lot has to do with the bullet's shape(ogive). Some bullets just hit the rifling sooner than others. A lot of the European guns are famous for their short leads ( throat).

Sounds like you're going about it ok by doing the plunk test. Just be sure to lower that powder load when you drop the recommended col.

I did not reset my powder. I was charging 2 grains shy of max load at 4.6.

You should be ok being .2 grains off of the max load. The 9mm is a very unforgiving round. Not a lot of room to work with. Col and powder charges need to be checked and double checked. Going from a Col of 1.1 to 1.07 don't seem to be much of a drop, but with the hi pressure 9mm it could be.

well with this charge you can't double charge that is for sure - one charge fills it half way and the other fills it to the top. I still check powder charges every 10 rounds.

The CZ and BHP have very short leades (chamber) a LRN bullet has to be seated much deeper than a FMJ or for use in most any other 9mm.

1.075 to 1.080 for Missouri BC lead RN. Start with the lowest powder charge.

I had the same problem with LRN 115gr bullets. The problem was on my Kel Tec PF9. My original OAL was supposed to be 1.125", it wasn't till I got down to about 1.100" that the round would 'ker plunk'. I ended up making them all 1.095". I was using Power Pistol, starting load at the 1.125" was 6.0gr if I remember right, got a 'recipe' from Lyman that said using 5.0gr @ 1.060", I'm 5.2gr @ 1.095". No chronograph yet so I don't know how fast it is. There aren't any signs of overpressure that I can see, they feel about the same as Wal Mart stuff, maby a bit more 'snappy'. My Sigma didn't have any issues with the 1.125" OAL.

I remember a test, that was done by the American Rifleman staff, decades ago.

They had a jacketed bullet load, that pressure tested at 35,000 CUP. Seating the bullet 0.050 deeper brought the load to about 75,000 CUP.

As stated above, it is a TINY case, and small variations make LARGE differences. Not a cartridge for the beginner.

Back when I started loading the 9mm, about 50 years ago, the brass case thickness was wildly variable, and I found that a strong "press" check was necessary, to insure no bullet set back.

I also endeavor to size the snot out of the case, so there is a small ridge, at the base of the bullet. No bullet set back then.

I loaded 115gr. Berry plated RN at an OAL of 1.165 and it fed and functioned fine in my 5906, with 5.0 gr. of Unique.

A couple of things. My experience is the CZ's have the shortest throat of anything I load for or anything I read about. First thing I do is to establish the max OAL for all the 9mm's I load for. Then I set my max OAL length so everything I load for will function in all my pistols.

What you found is you can't necessarily take the OAL listed in the manual as a given the round will function in your pistols. If you load with a shorter OAL the pressure will be higher. If you load longer the pressure will be less. And that is only if you are using exactly the same bullet. Same grains but different bullet with the same OAL the pressure could be different because the seating depth can be different due to bullet length (even though they are the same grains and type). The way I keep track of this is to record and establish my max OAL. Notice with lead the CZ's are the shortest.

http://i860.photobucket.com/albums/a...pp2/9mmOAL.jpg

Good advice so far, interesting table above, and Rule3's post mirrors my experience with CZ. I've got a CZ Custom Shop SP-01, great gun! But, as others have mentioned, CZs have short leades, and requires the right shape bullet to avoid reducing the case volume via short OAL.

As has been mentioned, you need to be careful with 9mm, as it is a relatively high pressure round, and you don't want to get too cute with short OALs. Always start low with your new loads, and check for signs of pressure. Your powder throw sounds pretty stout for 1.07 OAL, especially for range fodder. You may be OK, but I personally would back down on the powder. Definitely pay close attention if you fire those rounds.

I had been loading some Precision Bullet LFPs, and had to size them at 1.08 OAL to keep from hitting the rifling in the CZ (I had slide lock up with longer OAL...). I used 4.2 gr of W-231, and that was OK, but I ended up ordering a different bullet shape so I can bring the OAL out to a more comfortable length (my primers were definitely ironed pretty flat with that load). The flat point bullet shape hits the rifling quicker than RN bullets.

I would think that your RN should allow you to come out with your OAL, but I know you did the drop test, so it just depends on the bullet... I'd find a new bullet, if I were you. In the meantime, I'd reduce your powder to around 4.2 gr of W-231, at your 1.07 OAL with 115gr lead round nose in that gun, and I'd be careful to check how they are working. To put this in perspective, I use 4.3gr of W-231 with Precision Bullet 115gr LFP, with an OAL of 1.16 in other 9mm guns, and that load shoots well.

Hope this helps, be safe.

I'm using 115 gr Berry plated RN and 4.5 gr WW231 with OAL of 1.15. I set it up initially with a 3913 and used just enough powder to make the action function reliably. Then I went to the M&P 9 and now added a Ruger LC9; all shooting the same load. No indications of excess pressure and have fired thousands of them.

Your load sounds good to me, in fact I've used that very combo at one point... However. 4.5gr with a 115gr plated bullet @1.15 AOL is a different load than 4.6 gr with a 115 gr lead bullet @ 1.07 AOL...

Again, OP may be OK, but I would back down and/or be careful to check the results. But hey, that's just me, and my experience, YMMV...

I went back yesterday afternoon and worked a little bit with it and was able to get 1.09 COL to work OK with my CZ with the 115 grain LRN bullets. Powder charges are hovering at about 4.4 of HP38. That makes feel a little better about it. Another lesson learned here on the potential impact of deviating from the data load sheets. Really did not know the impact of reducing the COL, which reduces the size of the powder chamber (that was probably an incorrect term).
I appreciate all of the input.