9mm Major With Hs-6 And 3n37

[mleeber]

Just got all the stuff I need for 9mm Major. I have Federal small rifle primers, HS-6 and 3N37, Zero 125gr JHP, and my G17 with 4-port KKM compensated bbl.

The HS-6 and 3N37 were reccomendations from this board and others.

2 questions:

Where should I start as far as charge goes?

Is there one brass that is better than another (I have about 25000 empties from every maker) and is Nickel better than brass?

Thanks!

[G17comp]

Hello,

I don't have any experience with 3n37, but I do use HS6 in my G17/KKM open gun. I have only used FMJ Zero's with my loads, but it should be comparable. I started at 7.0 gr of HS6, and worked my way up (to around 7.8-8.0). I use mixed range brass and leave it lay, and I haven't had any problems using mixed, fired brass (within reason). Be very careful about your OAL with major loads. I have had almost 100fps difference just in .005 less OAL. Also, between a 92 degree day, and a 68 degree day, I get about 30-40fps more from the same loads. This hasn't hurt me, but don't chrono at 167pf on a cool day, and then go to a match on a hot, humid day or you might be upset! I found that between N350 and HS6 at the same PF, I get less pressure signs with HS6. I don't know how the 3n37 will behave, but post some results and I might give it a try. I found that between N350 and HS6 at the same PF, I get less pressure signs with HS6. Good luck shooting Glock in Open, it's a lot of fun!

Brian F.

[.40AET]

For the 3N37, work up from 7.4g-8.2g in .2g increments. Watch for pressure signs. I'm running 7.8 with MG 124g CMJ's, Fed SR primers and mixed brass. Go with the longest OAL that your mags will function 100% with. I don't have temperature problems with the powder at all. The load went 169pf at 2 different major matches. I do use same headstamp at a major match just to eliminate some of the problems with seating primers in crappy brass. 3N37 is a lot cleaner than the HS-6. I only shot about 400 rounds of HS-6 and moved on to better powders.

Good luck,

Welcome to the Dark Side

[mleeber]

Thanks Gents! Heading for the basement now to start the Dillon up.

[George]

Load as long as your mags will function. Most stock glock mags will accept up to 1.160" OAL. YMMV

Some extended base pads mess with the tube dimensions and may require a shorter OAL (mine does) and you need to be careful at any OAL under 1.150"

I like the HS6 option. It's exactly the same as WW540 which is what I use (discontinued over here). I use 8.6 grains to get 1370ish under a 124gr JHP (.355" diameter) at 1.135" OAL. So basically, you can see that 7.0 is a pretty low starting point for HS6/WW540 under even a 125. Do make sure the bullet is a .355" 9mm one and not larger, or you may experience overpressure before you get the V you need.

I would recommend using 7.5 grains HS6 as a starting point and work it up from there with the OAL kept as long as possible. Try 1.155" OAL as a fairly safe start if you can't settle the mag length issue right off.

Crimp only as much as needed to flatten the case mouth back down against the bullet or you will increase neck/bullet release tension and go overpressure when you shouldn't.

BTW, the WW540/HS6 burns so clean in my setup that it barely needs wiping to cleanup ;-)

BTW, BTW, you may find the Glock striker having problems touching off the rifle primers (harder) if it doesn't have a full power striker spring. I have to use Federal SP100's to get my lightened striker to work 100%. No pressure issues at 170+ PF. I tested them up to 180PF when I did my load development. They got flat, but they never blew :-)

9mm major is bleeding edge, but so was .38 super when it was adopted.

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Regards,

Edited September 24, 2005 by George

[mleeber]

Just loaded some HS-6 rounds. 50 with 7.0gr, 50 with 7.4, 25 with 7.6 and 25 with 7.8. Mixed brass. I had 200 CCI small rifle primers so I will use them up before breaking in to my Federal small rifle.

The Striker spring may be an issue. I intend to use a reduced power spring and either a Lightning Strike or a modified Glock striker. I thought there may be a problem setting off a rifle primer with this combo. Right now the gun is box stock except for the KKM barrel. I may leave it this way until I find a load that I like and then I will do the rest of the work.

I have to get my Chrono woes taken care of before I post results (am fighting a stange situation with my CED and the Infrared Lighting system). CED has been great but we are both stumped so far.

Thanks for all the help!

[George]

Just for fun, here is some of my workup data at 1.155" OAL with a 124gr JHP over WW540/HS6:

8.0 = 1224 fps

8.2 = 1250 fps

8.7 = 1328 fps

I settled at 8.6 for 1368 fps at 1.130" OAL due to mag loaded length problems. This is a very short and hot round! I do not advise just duplicating anything here, but I thought you might want to see what my predictions are for where HS6/WW540 ought to wind you up at a typical Glock OAL.

Remember, this is with a .355" diameter bullet in a .355" bore. All bets are off if these dimensions are not very similar.

The difference in your 125 vs my 124 grain bullet will also result in a couple percent charge reduction for you (say 8.3 vs 8.4 or something similar).

I fully expect you to need 8 grains + to get safely over 165 PF at a safe OAL in the Glock. Let us know when you can chrono. I would wait until I had a working chrono to test anything myself.

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Regards,

[mleeber]

The Chrono part has been the most frustrating.... I have been to the range 3 times with 4 guns and 1000 rounds and the results were goofy. CED sent me a whole 2nd unit but indoors under the IR we are still getting som strange results. I don't really have access to an outdoor range.

On another note, if any of you guys have pictures of cases that show pressure signs I sure would like to see them. I have been reloading for 20+ years but have always been well within the powder manufacturer's specs. I am especially interested in Glock case pics because some of the "normal" rounds have primers that appear to flow into the cutout for the firing pin which would make it tough to use that as a pressure sign.

Thanks!

Mark

[George]

When it flows into the striker hole enough to get sliced off as the case ejects, then you've got some primer flow ;-)

But seriously, it;s the outer ring of the primer to case fit to watch. If it starts blending in with the case head, then you've really got some primer flow!

Watch for bright bands and bulges in the case base just ahead of the extractor groove. Look for tough extraction signs like excess case exterior abrasions and extractor rim gouging and failures to extract. Bad juju there.

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Regards,

[mleeber]

Just went down to start som 3N37 loads and the case is pretty full at 6.8gr. Are the major loads with 3N37 compressed?

I am using a Pact electronic scale, maybe I need to break out my 5-0-5 scale????

[.40AET]

Just went down to start som 3N37 loads and the case is pretty full at 6.8gr

Keep pourin'

Work up in .2g increments until you make major.

Edited September 24, 2005 by .40AET

[George]

That's why I like HS6/WW540 for 9mm short loading. 8.6 of 540/HS6 under a 124 at 1.130" is NOT a compressed load. The 3N37 will probably be a compressed load at 165+ PF.

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Regards,

[mleeber]

New problem....

Just got back from the range and none of the major rounds fed in my new KKM barrel. They were too long. I slammed my palm against the rear of the slide and it still would not close. In examining the round I see gouges in the bullet from the lands in the barrel. The OAL is 1.153 and the bullet is a Zero 125gr JHP that is .355 in diameter.

I was able to shoot some of the reloads I brought for my G34. They were Zero 147gr JHP with an OAL of 1.104 but some of those needed some encouragement to feed.

I have tried a resized 9mm case in the barrel and it fits fine. I also tried one of the spent cases from my 34 and is it snug which I would expect as the G34 chamber is not as tight as the KKM.

Any ideas????

Also, for those of you running KKM 4-Port comps on a G17 what weight recoil spring are you using?

Thanks!

[diehli]

Sounds like you have zero free bore to me.

[George]

Take the darned thang to a good smith and have him ream the throat until this stops happening. Do not under any circumstances attempt to shoot high pressure pistol cartridges when the bullet has no freebore upon being chambered. This increases pressures astronomically. The 9mm is a kinda snappy cartridge in it's normal PF, let alone bumped.

Before I went 9major, I took the Barsto bbl for my 17L to a smith and had him check freebore for several dummy rounds I prepped and then I also had him make sure that my chamber had a couple (3-4) thousandths headspace clearance. He had to ream the chamber a tad, but the freebore was OK to start, yours is NOT. That is scary in an aftermarket bbl being sold to Glock hotrodders ;-/

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Regards,

[mleeber]

I will be speaking to KKM tomorrow. This was supposed to be a drop in 9mm Major barrel with 4 port comp. The first one the sent me was a 3 port and now I have one that appears to be their gunsmith fit version not the drop in.

I also have a federal arms threaded barrel that should be here soon but no comp for it. Who's comp should I consider? I hear Brian Hawley makes some good ones.....

[George]

I have seen a few pieces of Brian's work and it is good.

Glad to hear that you found the culprit. Me, I would have had a smith fit the bbl in the first place (my Barsto was). Things run real well when they are custom fitted. But thats just me ;-)

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Regards

[fishnfst]

I have one of Brians comp and it's great.... Functions flawlessly and does a good job of keeping the muzzle down compared to the original one from kkm....