Home Forums Reloading Handgun Reloading Reloading question, 9mm Parabellum

I am mystified by the variation between the powder amounts/velocities listed by the Alliant reloading data center for 9mm Parabellum (aka, Luger) compared to the data listed at other sites.

I recently purchased some Berry 124 grain "target" hollow pointed bullets. Berry suggests that the reloader use data for FMJ bullets of the same weight.

The Berry THP is 14.3mm long, same as the 124 grain Golddot. Alliant recommends a max charge weight of 5.8 grains of Unique (a powder I have ample supplies of) for the 124 grain Golddot.

Cross referencing, I see that Western Powder lists the Berry 124 grain THP. Western Powder has data for AA#2, a powder with a very similar burn rate to Unique. COAL is identical. Max charge listed is 4.2 grains of AA#2. The Alliant charge weight is 42% higher than the WP data.

Hodgdon also has data for the Berry, albeit the hollow BASE round nose and a longer COAL. They recommend a max load of 4.4 grains of Universal...another powder with a burn rate very similar to Unique. Switching to a 125 grain hollowpointby Hornady, Hodgdon's shows a max charge weight of 3.3 grains. 5.8 grains is 75% more than 3.3 grains.

Yeah, I know, similar is not the same as identical. But holy crap! 75% is a huge difference. It looks like Alliant is the outlier. What gives?

You said it. Similar is not the same as identical.

This is why every handloader should own a chronograph.

I've run into major load discrepancies with 22/250 and 45/70 in the various load manuals and a chrono really helped me out.

Accurate #2 is a bit faster than Unique, according to my burn rate chart.

Also, bullets with identical OAL's can still have different bearing surface lengths, i.e. parallel side length.

Accurate #2 is much. Lose to Bullseye than to Unique. It's a little slower than Bullseye, is still a very fast burn speed powder. In a practical use case Accurate #5 is the powder that is closer in burn speed to Unique but it is slower.

Mark in GA.

I guess we must be lookin' at different burn rate charts.

Here's the one I use & Accurate #2 is not really close to BE.

MM

Hodgdon Burn Rate Chart

I load 5.5 grains of Unique in my 9mm 115gr HP loads.

I shoot that exact load too......

It's very accurate in my handguns.

My brother came out this afternoon. Unfortunately, he scored a direct hit on the chrony with his fifth shot. We were still baselining commercial ammo.

I think part of the problem might be due to this:
http://eatonrapidsjoe.blogspot.com/2015/02/reloading-9mm-parabellum-saami-mistake.html

We ended up at 4.4 grains of Unique with 124 grain Berry THP bullets and a COAL of 1.125"

Could be the problem..........

FWIW, I load 6.7 gr of PowerPistol with a 115 gr bullet & 6.2 gr with a 124.

Unique is very close to PP so I don't expect you'll have any issue with 5.8 gr, but you can always load a few rounds lower & work up.

You do have to have enough pressure to insure consistent functioning of the gun.

MM

The pressures in 9mm skyrocket when bullets are seated even a tiny bit too deep.

MM: What are you shooting that out of?

2 Glock 19's, a S&W M&P, & 3 Beretta 92's with one of them being a 92 Compact.

Much more of the 115's than the 124's.

Unique is a very good powder, but PP is much cleaner.

MM

I don't mean to embarrass you but you are, like, my hero. I wanna be like you when I grow up. At least I want to have those same guns.

I never understood the need to have the insides of the cases be clean after shooting. A little bit of soot never hurt me. Heck, graphite is a fine dry lube and graphite is just another form of soot.

Best regards,

-Joe

Laughin' here.

Don't care too much about the cases, but the less dirt & powder residue on the insides of the guns, the less frequently I have to clean & I like that.

My wife & 2 boys shoot, so lots of excuses for more guns.

MM

For those who care about such things, Widener's has 124 grain, .355" Gold Dot bullets in stock at a very reasonable price.

If you call them on the phone you will hear much laughter. Somebody is having a birthday party in the office today.

-Joe