9mm, how full is to full?

[searly]

I'm fairly new to reloading; I've loaded mostly large handgun cartridges such as 45LC and 44 mag.  Normally in those cartridges there is plenty of space inside the case after adding your powder.  That does not seem to be the case with 9mm or even the 40 s&w.  After following several recommended recipes, the cases seem awfully full with no space between the powder and bullet after seating. This makes me nervous.  I've checked the powder with a powder scale.  Recalibrated the scale and checked again but the darn things are so full that it just seems dangerous.  I've segregated these rounds until I find out if I'm making some kind of rookie mistake.  The "recipe" I've followed for the 9mm is 124 gr GDHP in front of 5.7 gr of unique.

Please point out my mistake if any.

Searly

[Dill45]

Is this a recipe you got from a reloading manual? If not I wouldn't use it till you checked it out in a reloading manual.  I have no personal experience using unique in 9mm, so I'm unsure of the load that you are using.

That all being said, from my experiences, the best accuracy I've ever achieved in many of my straight wall rifle rounds was where the powder was either slightly compressed or just right at the base of the bullet.  From what I've been told, and read, is that with a full case it allows for the most consistent ignition and burn of the powder since it's not moving around in the case.  That is not to say try to fill every case to the max with powder because that is dangerous.  Some powders simply can't be loaded with that much powder because it would be to much powder, and to much pressure.

Again, check it out in a reloading manual.  Personally I would start out at a starting load and work up. 

[OR-E-Gun Bill]

Checking in the Alliant online reloading guide they show a recipe using 5.8 gr. Unique with the 124 gr. GDHP you mentioned.
I just loaded 5.7 gr. Unique into a 9mm case just to see what it looks like and personally I would not load a 124 gr. bullet into the case, as it would be very compressed, in fact I'm not sure it would even fit.

I load 124 gr. Hornady HP-XPT bullets and 4.8 gr. of Unique. Hornady's manual shows 5.0 gr. as Maximum.

Bill

[searly]

Thanks for the reply.  The “recipe” came directly from the Alliant web site.  I actually backed off the powder by a tenth.  Slightly compressed is a very good description of what is happening.

Searly

[searly]

Oh it'll fit, but it's freakn scary to a novice like me.  I've decided I'm going to pull these, drop back ten and punt.

Searly

[Steve P]

You are in the ballpark as far as being a "book" load, but you will find it barks a little, depending on the weight of the gun you are shooting it in.  My load is 5.0 grains Unique and a 122TC cast bullet.  Snappy and acurate. 

Steve

[searly]

These loads were intended for a old STAR 9mm,  the little brother to my STAR PD.  I find both to be fine weapons but the 9mm seems a bit on the heavy side.  Perhaps I'll weigh it when I get home.

Searly

[Graybeard]

Compressed loads are not bad loads and in fact might be safer than many that are not compressed. What it most often means if the load is slightly compressed is that the powder is about as slow as is useful in the case with that bullet weight. Most of the time so long as it's a book load it could mean even lower pressure than loads that use a less than full charge.

If the powder is a ball powder stick to what the recipe says don't go playing around adding or taking away from it.

Compressed loads are not a problem so long as they are what the book recipe called for.

[OR-E-Gun Bill]

Searly, just out of curiosity could you measure the length of the Speer Gold Dot HP's?
The Hornady XPT bullets I have are .573". My guess is the Speer bullets are a bit shorter after looking at the design differences.



Always learning
Bill

[searly]

OR-E-Gun Bill,  I'll measure it as soon as I get home today.

Searly

[searly]

OR-E-Gun Bill,

I have three 9mm bullets.
124 grain GDHP is .549 in length
115 XTP .541
115 WW JHP .535

Searly

[Autorim]

You need to check overall cartridge length for functioning. Different bullet profiles are seated to different depths by most seating dies. A change in OAL with a case as small as the 9mm will change pressure.

I have fired 5.0 and 5.5 grains of Unique behind the Remington 124 grain JHP. Both loads function, but I get better accuracy with AA No. 5 with that bullet. I am shooting a pair of Springfield XDM 9's.

[bremraf]

I load 8 grains bluedot and 115 gr fmjs or xtps.... scary compressed but very accurate in my sig p6(offhand groups 2-3 inches at 10 paces)!  Oh yeah there's some bark to these bad boys.. makes me feel a little more confident in my self defense loads!

[Bill In SC]

That 8 grains of bluedot load is one I have been using for years.

Loading 115 grain Remington or Winchester bulk JHP's, it makes a fine and accurate load.

Shooting them out of G17 and G19.

Bill