Minimum COL for 115 grain plated round nose 9mm?

If you're not loaded to max you could probably go as far as 1.065" as listed for the Lyman 120 gr RN lead bullet. Some one check me on this please. You can certainly re-seat the bullet slightly deeper.

You need to be care with TG for it's sensitive to case volume. Step down in steps checking for over pressure signs.

Blue68f100 said:

You need to be care with TG for it's sensitive to case volume. Step down in steps checking for over pressure signs.

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That's what I advise. Start over using your new COAL. Start low and work your loads back up checking for signs of overpressure as you go. FYI, yes you can reseat your existing loads to your new COAL. But you may want to reread some of the previous advice before doing so.

shovel99 said:

Hi Guys,
My brother's Kahr CW9 is producing FTF with light, off center strikes with my reloads. Sent it to Kahr and it came back with same problem. It shoots factory Hornady Critical Defense (short ogive) perfectly. Fellow at the Kahr forum suggested seating bullets a bit deeper. shovel99

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So are you saying light off center strikes of the primers and FTFs on the Kahr are caused by the OAL of your ammo? Hmmmmm....I don't understand that logic

Did your ever plunk the Kahr's barrel and find out what it's max OAL is? If not that is what you really need to do first...

Interesting... I just loaded my first 9mm in about 10 years... for my Kahr CW9 and CM9. I seated both the 124 plated and 147 plated at 1.135". When researching my loads, there was a huge difference in OAL... but there was also a switcheroo I hadn't noticed before...

My Speer data gave a specific COAL tested... in this instance it was 1.130" with the 147grn FMJ, certainly close enough to my 1.135" setting. My Alliant data (I was loading BE-86) gave a 'minimum OAL' of 1.120"... they didn't specifically state their tested OAL. Whatever it was, it must have been close to Speer's data... the max charge was the same (5.1grn) and the velocity as tested was almost identical... but, again, they didn't give the testing device (pistol or test barrel, etc.)

Question for the OP... did you crimp your rounds? If you really mashed them with a taper or roll crimp, I wouldn't advise trying to seat them deeper. Did you chamber a round and then extract it to see if there were any marks on the bullet? ...from hitting the chamber throat or rifling?

As an aside, I had the same problem as your brother's CW... only in a P45. Constant misfires and high primer strikes. I traced it to an exceptionally tight... or short... chamber, not allowing the pistol slide to go absolutely fully into battery.

As an aside #2... I run Hornady Critical Duty 135's in all my Kahr 9's... it's an excellent performer.

BDS has a mod here where you drill a hole in the side of a disk and insert a machine screw.
(I will post the link when I dig it up )
You can then adjust the machine screw to get a charge between disk sizes.
I would either use your .37 disk hole or maybe the .40 hole if you are concerned about messing up the .37 one.
I have an Autodisk measure and a Pro autodisk measure and use both but have pretty much replaced them with the new Lee Autodrum which lets you dial in the charge.
Titegroup is dense (smaller disk hole for it's weight) so it is a bit harder to meter as well. (Think if the powder took up twice as much space for the same weight to get the same charge swing would take + or - twice the powder volume wise)
I am surprised your 37 CC Lee disk is throwing charges 4.0 to 4.4 grains of Titegroup.
4 of a grain is a large charge swing in a 9mm case and a very large swing with Titegroup IMO.
Hodgdon data
115 GR. SPR GDHP Hodgdon Titegroup .355" 1.125" 4.5 1135 29,500 CUP 4.8 1158 30,500 CUP
Lyman show 4 to 4.5gr of Titegroup with a 115 JHP @1.09
Titegroup is more finicky about case volume/OAL than some other powders IMO.
As mentioned by other posters if you shorten the OAL you should work up again.
Also I would say by the time you see flattened primers in 9mm you are way to high pressure wise.
Please be careful with Titegroup, it is not know to be "forgiving"

Yes you can reseat the bullets deeper. (but be aware that the OAL change will increase pressure, depending on the powder charge you may or may not be ok pressure wise)


" Fellow at the Kahr forum suggested seating bullets a bit deeper."
If the bullets "plunk" ok I don't see how seating them deeper is going to change light off center primer strikes. Sort of off center is ok as long as they go bang.
(search for plunk test here, Walkalong had a excellent post on it)
If they don't plunk, OAL needs to be adjusted so they do.
Do they fire on a second try? If so that would tend to make me think the primers need to be seated deeper.
Maybe the reason you are getting light strikes is because the primers are not seated fully.
Firing pin hits primer, drives primer farther into the case instead of making the proper "dent". Firing pin hits correctly seated primer, no primer movement, nice dent=bang.


On a different note the 9mm RMR 124gr flatpoint shoots well for me, I like it, but with 124s your going to need less powder so a smaller disk or the screw adjuster.
RMR offers us a 5% discount with a code. (at the start of BDS's PIF thread here or PM me)

Hope you get it worked out.

Charlie98 said:

As an aside, I had the same problem as your brother's CW... only in a P45. Constant misfires and high primer strikes. I traced it to an exceptionally tight... or short... chamber, not allowing the pistol slide to go absolutely fully into battery.

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Exactly my thoughts.

The reason the primer strike is off-center is due to the way the barrel locks up when a round is chambered. The rear of the barrel drops down to "unlock" from the slide. The reverse happens when a round is chambered.

Plunk the failed rounds in the barrel of the suspect gun to see if it is a seating depth problem.

If some fired and some did not, then you may be right on the edge of what will fit. The danger here is that the bullet may be starting out jammed into the lands and can create a pressure spike. The fact that the powder is TG is not good, IMHO. If you are right on the edge, you can try seating them another 0.020" deeper. I would be hesitant to seat them deeper in already loaded rounds, instead I would make some new test loads for your brother's gun first, dropping the charge down a little as well. Shoot up the others in the numerous other guns you have.

May want to make sure your TC is removing all the flaring. A little wide at the mouth can cause the bullet to FTFeed too.

F2F = failure to feed or failure to fire? OP said there was a firing pin mark so failure to fire seems the verdict.
COL affects feeding so failure to feed is also a consideration.
So, which is it?

Link to BDSs Lee disk mod
https://www.thehighroad.org/index.p...ze-available-is-it-0-30.842468/#post-10944266

► The Min OAL for a auto pistol cartridge is controlled by the cartridge case. Since most pistol cartridges are fairly cylindrical on the exterior, to obtain the necessary extra strength near the head, auto pistol cartridges start to thicken the wall on the interior as you get closer to the rim. You can easily see this on your 9mm cases by setting your caliper to 0.355" and sliding the ID tines into the case. On most 9mm cases (without the step) this starts to occur about 0.27 to 0.30" into the case. That's the maximum seating depth for a 0.355" bullet due to the restricted internal diameter. You can easily see the thickness increase is this very accurate 3D model...



In addition to that physical restriction, SAAMI and most reloaders agree that 1.000" is the Min OAL for reliable feeding.

► The OALs listed with load data are not a recommended cartridge OAL. Load data is merely a lab report, and the OAL shown is merely part of the report. What the lab is basically saying is, "This is what we used and no one died. Now, go make it work for you." If you can use their OAL, well then that's fine. If you have to go with a shorter OAL than shown, then you should exercise caution and also reduce your powder. 'Reduce the powder by how much ?' is where you begin to need a chrono.


Hope this helps.
.

If you seat them to deep, ( making your cartridge too short) you may end up with feeding issues.

Dudedog said:

I am surprised your 37 CC Lee disk is throwing charges 4.0 to 4.4 grains of Titegroup.
4 of a grain is a large charge swing in a 9mm case and a very large swing with Titegroup IMO.

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Dudedog and OP

I am surprised as well that there is a big swing 4.0-4.4 as you stated. With a good steady rhythm on the ram it should not do that.

My Lee Disk .37 consistently throws Titegroup at 4.4 gr with an occasional +/- 0.1....in fact I loaded 1000 rounds last month and have been loading 9mm again with it the last 2 days...I have to use the disk because my Lee Powder Charge bar always bridges bad at that load.



Back to the OP's issue...if you have fully seated the primers and the OAL for that Kahr barrel is correct OAL is not going to cause light primer strikes and off center strikes, what the Kahr forum person told you is not correct....If that gun was sent in to Kahr for light primer strikes before and it is till doing it it needs to go back...its a gun problem, most like firing pin and/or pin spring related, not an OAL problem

The screw mod works well, better than the lee adjustable charge bar for small volume charges.
I haven't loaded any Titegroup in a while but on most powders I was generally + or - .1 (.2 swing)or less with the Lee disk measure.

All 5 or 6 factory round fired fine? Where there any issues with the factory ammo?
Again did you try to shoot of the reloads that failed to fire a second time?
What was the result if you did?
Still leaning towards a primer seating issue not the gun if it works fine with factory ammo.

I would like to note however that I am frequently wrong and get reminded of that on occasion

Chances are Kahr testfired your pistol... with factory ammo. The fact you are having problems with your reloads should be an indicator, I would if it were me... and so I did when I had problems with my P45. In my case, I had FTFires with factory ammos, too.

Kahr pistols are excellent pistols, but they kick out a problem child now and then... everyone does.