Need some 9mm 125gr advice

[thorn]

I'm starting my first round of ...erm... rounds... using Hornady 125gr FMJ bullets. One day I'll probably switch to plated, but I decided I'd start with a more mainstream (aka: expensive as hell) component to minimize some guesswork.

But of course, guesswork is popping up anyway. I'm using near-minimum charges of HS-6 to start, and can't find an OAL for that powder and this particular bullet. Here's some load data I have found:
125 GR. LCN HS-6 1.125" min 5.9 1023 max 6.6 1124
125 GR. SIE FMJ HS-6 1.090" min 6.4 1131 max 6.8 1169
130 GR. SIE FMJ HS-6 1.120" min 6.3 981 max 6.6 1090
147 GR. HDY XTP HS-6 1.100" min 4.3 773 max 5.0 885 I also put some WWB 115 Factory 9mm on my caliper: 1.160".

Now I'll go ahead and say that I realize that the data listed is only what the company tested, and that it means that THIS particular combo (powder + bullet + OAL) was "safe and ok". But what kinda throws a wrench into my thinking is this:

The 125 lead is longer than 125 FMJ. 130 is shorter, 147 is in the middle - and WWB is almost at SAAMI max length. Huh? Why is Winchester loading their bullet so high? My guess is that it's erring towards very low pressures for safety, and their hope that it will feed the most reliably in most guns.

Based on a ton of reading others' discussions on their recipes, it appears to me that i'm free (within powder safety levels) to use anything from 1.090 - 1.160. The 1.090 seems awfully short to me, when I compare it to the WWB... honestly, I'm a bit afraid to seat it that low.

My first instinct is to just use 1.125" @ 6.2gr and see how well it performs.
If anyone has a better way for me to approach it (or possibly official Hornady data) I'd appreciate all advice. :)

thorn

[CaptToyota]

Set the FMJ @ 1.140 -1.155" and run with it. Don't really know why anybody want to seat a FMJ shorter than 1.140" in the first place.

I try to run all my FMJ at 1.150".


125 OAL is determined by the case mouth to drive band relation, similar to seating SWC in 45acp, but slight deeper.

[saunderscc]

If I may slide this over to copper plated RN 9mm, any advice on what to set the OAL? I have 124 gr, with 4.6 grains WSF and I had 1.128 with some fail to feeds today. I was thinking about dropping it down to 1.095. I did have FTE for a few of them as well. It was always hit or miss with mine.

[CZ93X62]

Complex issue, more so than meets the eye at first glance.

Ogive shape can really throw a wrench in things. In absence of hard OAL data, I try to load 9mm, 40 S&W, and 10mm as long as possible but still fit in the pistol magazine and not have the bullet's ogive contacting the rifling origin. Start with minimum charges, working up slowly to the performance level you are seeking.

[thorn]

Thanks for the feedback.

1.150 is indeed a level that feels mathematically comfortable in my head... I'll also see if i can smoke some bullets tonight, put them in the actual chamber, and see if i can tell how much rifling contact i'm getting.

Much appreciated. :)

thorn

[RustyFN]

If I may slide this over to copper plated RN 9mm, any advice on what to set the OAL? I have 124 gr, with 4.6 grains WSF and I had 1.128 with some fail to feeds today. I was thinking about dropping it down to 1.095. I did have FTE for a few of them as well. It was always hit or miss with mine.
I load all of my 115 and 124 plated RN at 1.135. Works good in my Glock and CZ.
Rusty

[Steve Koski]

Saunders,

What gun are you using?

What is the listed min and max powder charge for WSF and a 125 grain jacketed and plated bullet? And what manual did you get this from?

Koski

[saunderscc]

Saunders,

What gun are you using?

What is the listed min and max powder charge for WSF and a 125 grain jacketed and plated bullet? And what manual did you get this from?

Koski

I am using a G26. The book I have is the Modern Reloading. I have that because I am using a LCT. I am also using the 124 grain copper plated bullets and the 124gr load data for lead bullets. The listed min charge is 4.0 gr and the max charge is 4.7 gr. There is no data for copper plated in the book for WSF so I went with the Lead bullets. Should I have gone with Jacketed load data? Or a mix.

The jacketed data for 124 gr is start charge of 4.0 and max of 5.3. The OAL for both is 1.095.

And thanks so much for your help.