9mm coal

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brewer12345 said:
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?
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Plunk & Spin (as I call it) tells you THAT particular round fits your barrel. The problem is it it doesn't give you a "absolutely don't go any longer than this" type number. And without that number you don't know if the clearance is 0.002" or 0.050".

All production has manufacturing tolerances, and that includes your ammo production. So your OAL is not really a single number, but rather a ranges of numbers you say are good enough for your purposes. What if the bullet-to-barrel clearance for the cartridge you plunked is only 0.002", but you've decided your manufacturing tolerance is going to allow +/-0.007" ? You can see right off that cartridges +0.003" and longer are going to cause trouble. Cartridges out at the extreme +0.007" tolerance will interfere by +0.005" and may cause an OOB condition.

Since unplanned trips to the ER are not a favorite, I like to actually measure and KNOW the chamber length. In that way I can set my OAL so that even at my longest production length, every cartridge always has room in the chamber.

Hope this helps.
 
rfwobbly said:
Plunk & Spin (as I call it) tells you THAT particular round fits your barrel. The problem is it it doesn't give you a "absolutely don't go any longer than this" type number. And without that number you don't know if the clearance is 0.002" or 0.050".

All production has manufacturing tolerances, and that includes your ammo production. So your OAL is not really a single number, but rather a ranges of numbers you say are good enough for your purposes. What if the bullet-to-barrel clearance for the cartridge you plunked is only 0.002", but you've decided your manufacturing tolerance is going to allow +/-0.007" ? You can see right off that cartridges +0.003" and longer are going to cause trouble. Cartridges out at the extreme +0.007" tolerance will interfere by +0.005" and may cause an OOB condition.

Since unplanned trips to the ER are not a favorite, I like to actually measure and KNOW the chamber length. In that way I can set my OAL so that even at my longest production length, every cartridge always has room in the chamber.

Hope this helps.
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Yes, understood. The chamber of this barrel appreas cavernous since it plunked well over 1.20. I noticed my oal bouncing around within a few thousandths, so starting at 1.15 and knowing I have .07 or better to play with makes me comfy with a few thousandths of variance.
 
swg1 said:
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.
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Seating a bullet long isn't always the best course of action... some powders don't burn efficiently with more air space in the case, even a smallish case like the 9mm. Recent tests with W244 in the .45ACP demonstrated that to me, yet again.

swg1 said:
Seating a bullet too deep in a 9mm or similar round is where you can quickly run into trouble.
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True that. That's one of the reasons I don't use a 'high energy' powder like TiteGroup with a 147grn bullet in the 9mm.
 
Charlie98 said:
Seating a bullet long isn't always the best course of action... some powders don't burn efficiently with more air space in the case, even a smallish case like the 9mm. Recent tests with W244 in the .45ACP demonstrated that to me, yet again.
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Good info. What I am suggesting is a place to start in the absence of a published OAL for a particular combination. From there one makes informed judgments based on results. Thanks again for the info. :thumbup:

I'm just tossing this out there as sometimes it seems like lacking data some folks just go belly up instead of working through the problem.
 
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MFInc said:
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.
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No
I had a problem with one grain powder charges before I learned to put a vibrator on the powder measure when loading pistol ammo with 700X. All such underloads cleared the barrel.
 
swg1 said:
Good info. What I am suggesting is a place to start in the absence of a published OAL for a particular combination. From there one makes informed judgments based on results. Thanks again for the info. :thumbup:

I'm just tossing this out there as sometimes it seems like lacking data some folks just go belly up instead of working through the problem.
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I got you. I used to just seat everything at max COAL (assuming it chambered properly...) and called it a day, I don't anymore. Obviously, bulkier powders, and powders that require some room to work (think TrailBoss and Unique, etc...) are usually OK with that, but my general rule of thumb is smaller charges of faster powders don't like air space.
 
swg1 said:
Good info. What I am suggesting is a place to start in the absence of a published OAL for a particular combination. From there one makes informed judgments based on results. Thanks again for the info. :thumbup:

I'm just tossing this out there as sometimes it seems like lacking data some folks just go belly up instead of working through the problem.
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When I was working up loads for the Federal 105gr eFMJ I bought from Midway. Apparently, there is no published data for factory loads. Go figure! I started with measuring the projectiles, calculated the volume of the base, subtracted from the total case volume and solved for the height of the base. That gave me a range of seating depths. The factory loads were in that range but did not work in all of my 9mm pistols so I went to the deep end of the range and used mid-range powder charges for similar weight bullets. The result, 1.130” w/ 5.5gr HS-6, works reliably in every pistol tested.
AB390266-32DD-441F-917B-578894B8CA22.jpeg

That process has worked pretty well for me. YMMV, no deposit-no return, consult your physician etc.
 
Charlie98 said:
I got you. I used to just seat everything at max COAL (assuming it chambered properly...) and called it a day, I don't anymore. Obviously, bulkier powders, and powders that require some room to work (think TrailBoss and Unique, etc...) are usually OK with that, but my general rule of thumb is smaller charges of faster powders don't like air space.
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I’m looking at you, Blue Dot !
 
https://lewilson.com/pistol-max-gage

I’m a convert. These are based on SAAMI specs. If you’re loading for several pistols of the same caliber, these are easier IMO.

Note: It’s been demonstrated that some European 9mm can have shorter throats, CZ and Croatian Springfields in particular. Not always, but sometimes, so beware that your mileage may vary.
 
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brewer12345 said:
Yes, understood. The chamber of this barrel appears cavernous since it plunked well over 1.20". I noticed my OAL bouncing around within a few thousandths, so starting at 1.15 and knowing I have .07 or better to play with makes me comfy with a few thousandths of variance.
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Then, brother, that sounds good, but there 2 minor details in your statement to check.

1. You keep saying "Plunk". Maybe that's simply your nickname. But does it also spin at that length when fully inserted ? The cartridge has to plunk and spin in order to pass the test. If it won't spin, the the ogive is into the lands and it's doesn't pass.

2. Again, it's NOT the chamber by itself. It's the fit of that bullet into that chamber. This is important to understand, because at some point you'll receive different bullets. You must not assume that 2 bullets will give you the same clearances just because they weigh the same. You must not assume that the clearances will be the same for your other 9mm pistol. Change the bullet or the barrel and you need to start all over.

All the best.
 
rfwobbly said:
Then, brother, that sounds good, but there 2 minor details in your statement to check.

1. You keep saying "Plunk". Maybe that's simply your nickname. But does it also spin at that length when fully inserted ? The cartridge has to plunk and spin in order to pass the test. If it won't spin, the the ogive is into the lands and it's doesn't pass.

2. Again, it's NOT the chamber by itself. It's the fit of that bullet into that chamber. This is important to understand, because at some point you'll receive different bullets. You must not assume that 2 bullets will give you the same clearances just because they weigh the same. You must not assume that the clearances will be the same for your other 9mm pistol. Change the bullet or the barrel and you need to start all over.

All the best.
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Yes, they plunk and spin.

I cast multiple bullets for the same cartridge in many cases, so I know you start from scratch every time.

This has been really helpful. Thanks.
 
Just as a follow up, I ended up with an oal of 1.152 and 3.8 grains of titegroup for a target load. Feed and function is great, accuracy is good (I am rusty on handguns, so shoots better than me), and the cases basically fall at my feet.

Working on a 147 grain jhp load now at 1.14 oal and 3.4 grains of titegroup. I am really impressed with how well it meters.
 
I need to get some titegroup. I have enough CFE PIstol to load all the projectiles and primers I have right now so it will be a while. It would double as an experimental powder for some subsonic loads in my 308 and 223. A pound also goes a little further in pistols.
 
DMW1116 said:
I need to get some titegroup. I have enough CFE PIstol to load all the projectiles and primers I have right now so it will be a while. It would double as an experimental powder for some subsonic loads in my 308 and 223. A pound also goes a little further in pistols.
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The thing people criticize titegroup for is the narrow range of loads in most cartridges. I would say this is a fair knock on it. I did not go searching for the stuff, ended up buying some as part of a package deal before the panic. I like it, but the narrow range of loads makes me just a little nervous since I tend to like a large margin of safety. That said, it performs nicely and you get a lot of shots out of a pound of powder.
 
A always load 9mm long, but I use slower 9mm powders or low density powder.
The fastest powder I load in 9mm is general dynamics cbi, it burns kind of like hp38 but is super fluffy like trail boss so I can only fit 5.5gr.
 
Oh really? I haven’t looked into it. The range used for 9mm in CFE Pistol was about 0.6 grains from top to bottom. Is Titegroup smaller than that?
 
Wow That is narrow. I’m pretty confident powder measure will hold less than 0.1 grains each charge. But that’s with H335 and a total charge of 25 grains. How well does Titegroup meter out of a powder measure? H335 is pretty much the standard for repeatable flow from them.
 
DMW1116 said:
Wow That is narrow. I’m pretty confident powder measure will hold less than 0.1 grains each charge. But that’s with H335 and a total charge of 25 grains. How well does Titegroup meter out of a powder measure? H335 is pretty much the standard for repeatable flow from them.
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In my basic Lee powder measure it holds very, very tightly to the weight you set. In setting for 3.8 grains, 75% of the drops are exactly that and all the others I weighed were +/- .1 grains. If my chosen load were at the top of the range, I would not be all that happy, but that is generally the case for me anyway.
 
milsurpguy said:
A always load 9mm long, but I use slower 9mm powders or low density powder.
The fastest powder I load in 9mm is general dynamics cbi, it burns kind of like hp38 but is super fluffy like trail boss so I can only fit 5.5gr.
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How do you like the 5.5gr CBI for your 9mm? Have you tried CBI for .357 mag? I know it won't be a full mag load.
 
For RMR MPR's 1.150" COAL in a 9mm Dan Wesson. Chamber length, headspace, and recommended COALS from different manufacturers aside they have to feed reliably. 1911 9mm's and 45acp's can be finicky about COAL's. I stay within the recommended minimum/maximum COAL's and find a COAL that will feed well. I understand headspace, chamber length, and over pressure. I also understand COAL for reliable feeding.

I shoot more than one style of bullet in the same guns. In my three 9mm/45acp 1911's each have three different COALS for the same bullet for reliable feeding. I hate to muddy up the water here but if you load more than one style of bullet in the same gun and reliable feeding is important your COAL will have to be determined by and your guns and not any formula or chart. Bolt action rifle yes. Auto-loading pistols no.
 
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