9mm coal

[brewer12345]

I am finally fooling around with 9 on the bench, starting with a fmj rn 124 grain and 147 jhp load, both based on titegroup. I was planning on a minimum coal of 1.15, but both plunked at over 1 18. I noticed that saami max coal was 1.179, so I set everything to 1.165 which will hopefully avoid problems due to excess length. I know titegroup is touchy, so I am trying to keep lengths on the long side and go easy on my charges. Everything sound ok? Never messed with a cartridge this small before.

 

[kalielkslayer]

Without looking, I think 1.169 is max. Maybe a typo? I know I load one of my bullets at 1.151 and am near max length.

As long as they plunk and fit in the magazine, you should be good if you are under max COAL.

 

[BCR#1]

I try and keep all my FMJ loads to 1.150 if I can. An easy number to remember.

Bill

 

[lordpaxman]

I know titegroup is touchy, so I am trying to keep lengths on the long side and go easy on my charges.

I use Hodgdon’s online data as my starting point and so far KOW I’ve not had any issues if I stay within the lines. It is true if you shorten that COL without reducing charge weight you’re in unexplored territory. If you check online, select the 125gr bullet as well, you’ll see a SIE FMJ at 1.090”. And there’s a 147gr XTP at 1.100”. These are considerably less than your anticipated COL. If your bullet’s OAL is similar to the ones in the published data your seating depth will be similar as well. If you use these start charges at your much longer COL you’ll have anemic rounds. Good luck.

 

[DMW1116]

I ended up cobbling together a 115 gr load from several sources since neither my Lyman manual nor my Blue Book of 9mm had data for CFE Pistol in that weight for that bullet. Now that I think about it, I should probably re-evaluate that since the Hornady app has data. I didn’t have that when I started making 9mm at first.

For hollow points I use Hornadys COAL, since I use their XTP 115 and 147 gr bullets.

 

[Walkalong]

RN & JHPs will use different OAL's.

I generally use 1.130/1.135 OAL for 9MM plated or jacketed round nose. JHPs will be shorter.

 

[DMW1116]

Double post

 

[rfwobbly]

There are hard limits at work that can be explained and measured. These are part of the Science of Reloading.
► First you are confined to work within Physical Limits, which you should not go beyond in either direction. SAAMI suggests a minimum OAL of 1.000" for proper feeding, and a maximum OAL of 1.169" to be able to fit into the magazine. Those are your outer-most limits.

► Then inside those are what you might call your Safety Limits. Every bullet fits every gun maker's barrel a unique way. These generally limit the Max OAL. At the other end, you generally do not want to load shorter than the data from you load manual. That then becomes a useful Min OAL.

If we chart all this, it looks like...


Working within those hard OAL limits is usually a wide range for you to choose from. The final choice of your OAL is totally up to you. Some of this is experience, some is simply how that bullet feeds in your gun, some is knowing what the cartridge needs to perform. This is all part of your knowledge and becomes the Art of Reloading.


• To be successful you need to work inside all those limits.
• To be accurate the bullet should be seated at least 0.20" into the case.
• The OAL listed in your manual is not a suggestion. It is part of the lab report, just like the weight of powder, velocity and pressure.
• If you think you can ignore bullet-to-barrel fit, then here's a shamelessly stolen chart...


Hope this helps.

 

[brewer12345]

Ok, so I probably have a little room to play with the seating (smaller coal) if the test loads are problematic. I am trying to be conservative in a tiny case and a powder known to be easy to overdo. The rounds fit the mag and barrel without issue.

I suppose I could run everything through the dies to hit 1.15 before I try them.. hmmm...

 

[Charlie98]

I use TiteGroup with 115's and 124's... but not with 147's, preferring a slower powder like Unique.

I've loaded 124grn Berrys and HSM plated RN bullets over 4.2grn TG @ 1.135, which basically duplicates factory out of my short-barreled Kahrs. I don't have feeding issues at 1.135", even in the shorty CM9. I consider that a max load for me and my pistols, however... I don't see pressure signs, but I think I'm there regardless.

 

[rfwobbly]

The rounds fit the mag and barrel without issue.

And you know this how ? What are your exact limits ?

I suppose I could run everything through the dies to hit 1.15" before I try them..

Friend, this is not a guessing game. There are hard, physical limits at work, you cannot "suppose" anything. Did you not believe the second chart I posted ?

If you load longer than what the barrel can physically accept, the pistol can and will fire OOB and you could be seriously hurt.



This 'small cartridge' is dangerous, and guessing has dire consequences.

Just saying.

 

[brewer12345]

Ah, the firing OOB issue had escaped me. So help me out here: All of these rounds plunk and they are within SAAMI COAL max. Does that not equal fitting the barrel?

I loaded a few into the mag and they fit.

 

[NMexJim]

And you know this how ? What are your exact limits ?


Friend, this is not a guessing game. There are hard, physical limits at work, you cannot "suppose" anything. Did you not believe the second chart I posted ?

If you load longer than what the barrel can physically accept, the pistol can and will fire OOB and you could be seriously hurt.

View attachment 987534

This 'small cartridge' is dangerous, and guessing has dire consequences.

Just saying.

.
OOOhhhh, A CZ that bit the dirt!! I thought they were bulletproof so to speak!! Musta been that old-world craftsmanship

 

[brewer12345]

I revisited the reloading manual data I have and ran everything through to get to 1.15" or just over. Everything from over SAAMI max plunks. The Hornady round nose 124s I am using spec 1.15 in Hornady's data. The Win 147s I do not have specific data on, but the XTP data for the same weight is substantially shorter than 1.15. Will try all this morning and go slow, watching for pressure signs.

 

[Jim Watson]

There are so many different bullet profiles on the market and gunmakers paying little attention to SAAMI or CIP chamber throat standards, that every combination is a new world. CZs are notorious for short throats and a lot of competitors have had theirs reamed to take their preferred magazine length round.
Frex I loaded 115 gr HAPs to 1.115" for my Glock 43 in GSSF Pocket division and the similar looking Magnus (Zero) 115 gr Conical to 1.125" for my Glock 17. Most other target applications I load roundnose to a convenient length; 1.150" 147 plated, 1.142" 124 coated. OAL is not critical because I am loading to minor power factor, not maximum velocity.

If you load longer than what the barrel can physically accept, the pistol can and will fire OOB

Please discuss how a Browning tilt-lock action can fire out of battery with a pretty well centered firing pin strike.

 

[TransAmConvert]

Drop the bullet you want to use into the chamber. Measure from the bullet base to where the case head sits when a normal round is chambered. This measurement plus the bullet height minus about .020 will be your max OAL. Make sure it's not too short for the bullet profile. If good, work up the charge as usual. Just did a batch of Missouri 124s for my shadow @ 1.105 and they work great. Every bullet and chamber is different. In my M&P there's piles more room in the chamber to go longer, but not in the CZ.

 

[Otto]

.
OOOhhhh, A CZ that bit the dirt!! I thought they were bulletproof so to speak!! Musta been that old-world craftsmanship

No pistol is idiot proof.

 

[brewer12345]

Well, I shot my test rounds and everything went fine. I got lucky in that the most accurate charges that also consistently ran the action were smack in the middle of my charge tests. That means I can happily load up knowing that if the odd charge is .1 grain over my intended I am not pushing it with this powder, which seems to be known for a small working range of charges.

I have not shot a lot of pistol in the last year and I am rusty. Need to shoot more.

 

[GeoDudeFlorida]

I am finally fooling around with 9 on the bench, starting with a fmj rn 124 grain and 147 jhp load, both based on titegroup. I was planning on a minimum coal of 1.15, but both plunked at over 1 18. I noticed that saami max coal was 1.179, so I set everything to 1.165 which will hopefully avoid problems due to excess length. I know titegroup is touchy, so I am trying to keep lengths on the long side and go easy on my charges. Everything sound ok? Never messed with a cartridge this small before.

Not to get too technical or anything but your conflating cartridge overall length with seating depth. They're not the same but they are - or can be - related. Case overall length is a sloppy measure since case length varies at least a few thousandths, as do bullet overall lengths. Rims are different from maker-to-maker and while straight-wall cases, in particular pistol cases, don't tend to "stretch," the web and brass thickness varies. That's why hand-loaders who run close to maximum pressures or who want maximum reliability, accuracy, or some other variable... separate their cases by head-stamp and lot, if possible.

What you are looking for is how deeply you can seat your bullets in your cases with the powder you've chosen and still be in safe pressure territory according to the only measure you can take easily from each finished cartridge: the overall length from rim base to bullet nose. That's an average "load" - cleaned, trimmed, primed and sized case + powder charge + seated and crimped bullet - assuming none of your cases are more than a few percentage points different from one another - a generally safe assumption - and none of your bullets are more than a few percentage points different either - also a generally safe assumption.

The charts put out by the powder, die, press and bullet makers have done all of the hard math for you (subtracting seated bullet displacement from total case volume) to arrive at a good, safe, average seating depth which you can check by measuring the cartridge overall length. It's not real precise in my mind - then again, when I was a working machinist I considered +/- 0.001" a sloppy tolerance - you can drive a truck through a five thousandths tolerance (HINT: a human hair is about three thousandths)

That's also why those charts specify a bullet and a case, though. Try and stay close to the charts and you're safe. A longer seat may not be safer than a recommended seating depth since it also puts the bullet's ogive closer to the lands of your barrel and you can't be sure whether that's a good thing or a bad thing. Too many variables.

I think Wobbly posted a graphic some time back showing the powder volume to bullet base comparison. Very instructive.

 

[Jim Watson]

Olden days, Phil Sharpe listed seating depth instead of OAL. But that requires arithmetic.

 

[GeoDudeFlorida]

Olden days, Phil Sharpe listed seating depth instead of OAL. But that requires arithmetic.

Well, I'm not old but I am old-er. I remember having to do that math when I was 12 and my uncle taught me how to work up a load from scratch. h*Pi*r^2

 

[MFInc]

Would slightly longer be enough to cause a squib if you were on the lower end of the powder scale? Just curious. Some good Info here. Thanks.

 

[rfwobbly]

OOOhhhh, A CZ that bit the dirt!! I thought they were bulletproof so to speak!! Musta been that old-world craftsmanship

And this comment is helpful how ?

 

[swg1]

It's been pretty straight forward the last several years for me to favor seating the bullet as long as you can fit in the mag and that still fits in the chamber. You can use a felt marker to see if you are on the rifling or not and seat slightly deeper. Then start low with the charge and work up until a satisfactory load appears or max charge is met. High pressure signs are to be watched for at all times.

Seating a bullet too deep in a 9mm or similar round is where you can quickly run into trouble.

In other words, with firearm in hand, one can determine safe dimensions with some thought and due diligence for that firearm.

 

[brewer12345]

Would slightly longer be enough to cause a squib if you were on the lower end of the powder scale? Just curious. Some good Info here. Thanks.

At some low charge level, yes. I started at the listed min and although that load did not reliably work the action for either bullet, it was a reasonably powerful and accurate load.