9mm Major load for an Open STI with Comp!?

[nelly]

jayjay1, You should use only Jacketed Hollow points(any brand) or Montana Gold CMJ (Complete Metal Jacket) to avoid a melted Lead Buildup in your Compensator that will be a big Pain In the Ass to remove.These are all completely enclosed and won't melt into the Comp.

[lcs]

I use nothing but Xtreme plated bullets and I've done 1650fps with them.

1650 FPS. HOLY Sh..t Batman! Which Extreme are you running?

[kneelingatlas]

Regular plate 100gr

[Tino2212]

Hello: 7.6 grains of 3N37 is not going to make major. It will be more like 140-150PF even with a 124 grain bullet. You are going to be in the high 8 grain to 9.1grains for a 115 grain bullet. I like Auto Comp a lot better than 3N37. 3N37 burns hot and is hard on the hand with more muzzle flip. It also does some weird dot tracking at 175-180PF loads. If you have it, use it until you can find some better powders for major 9mm. Thanks, Eric

7.6 grains of 3n37 will definitely make major with a 124 grains bullet in a standard trubore barrel with no holes .

I made ( ipsc) major with 7.4 grains out of my tanfoglio gold custom pf was 166 .

[jayjay1]

Dear ladies and gents,

after a lot of back and forth, because of the law (CIP and SAAMI) and giving this high pressure ammo out of my hands, me and my friend (for whom this load should be) decided to do only a Minor load for his comp pistol.

I want to thank you all for your help and your support, and I want to apologize, that we turn now from Major to Minor.

I hope you can understand this decision and don´t argue with me because of that.

So I´m begging now - down on my knees - for your help to find a Minor load for his pistol.

He told me it is a STI Truebore with three long holes on top of the barrel and one long hole on each side, caliber is 9mm Luger.

May I ask you in general, if I need to take a slower powder to get the comp to work?

(I thought so, because I can generate more gas this way.)

If so, I do have some Acc. No. 5 and some N350.

Is one of them good for a Minor load in this comp pistol?

Sorry again, and I hope that you still will help me here.

Jay

[kneelingatlas]

So I take it this minor load needs to be within SAAMI specifications?

[jayjay1]

Hi Atlas!

Humm-well-no, not really, they need to be in the CIP specs, for being loaded and shot in Germany.

But with the stronger barrel and chamber of a STI Truebore there shouldn´t be a problem to go a little bit over it.

Without experience in Major loads in such a small case as the 9mm Luger I´m just a little bit shy in doing this.

Can you tell me how I have to load to get the comp working?

Is that right, with the lower powder to gain more gas?

[superdude]

May I ask you in general, if I need to take a slower powder to get the comp to work?

(I thought so, because I can generate more gas this way.)

If so, I do have some Acc. No. 5 and some N350.

Is one of them good for a Minor load in this comp pistol?

Yes, in general a slower power will be better. The greater the charge weight required for your desired velocity, the more gas it produces for the compensator. For example, if you have two powders that produce a velocity of 1000 fps, the one that requires more weight will provide more gas for the compensator.

[Tino2212]

A shooting buddy of mine also shoots minor with his open gun ( tanfoglio ) we use 115 grain bullets ( frontier ) and 3N37 we load 6,5 grains with a OAL of 29.4 mm .

He used to use 124 grain bullets but with 115 grain the gun is much flatter ( and for ipsc minor you dont have to use > 120 grain bullets like you have to in major wish we could use 115 like in uspsa ).

I my self shoot 9 major out of a custom build 2011 with a trubore barrel 124 grain bullets 7,1 grains N350 set at OAL 30 mm easily making major PF >167.

Edited June 30, 2014 by Tino2212

[kneelingatlas]

I don't quite understand the legality issue, but I'll take your word for it If you're no longer looking to make major, I would switch to the lightest bullets you can find (95/100); that way you can get the most gas to work the comp.

Another direction to try is super light bullets with a small charge of fast powder; the comp becomes no more than a barrel weight, but the recoil impulse is soft and quick. With this approach, you'll want to get the lightest recoil spring which will strip the next round off the mag (the smoother the bottom of your slide, brass and mags, the lower you can go), start with ~2.8gr and work your way up until the slide cycles reliably.

I shot some 115gr bullets with 3gr of Clays with a non comped Open gun and really enjoyed it Pew, pew, pew!

[Tino2212]

Keep in mind he still needs to make minimum PF for minor PF 125 .

[jayjay1]

Hm, Frontier bullets are copper plated, not FMJ, is that correct?

So, would H&N work too? (Easy to get here, so.)

Well, so I try to assume what you´ve said.

I should use FMJ´s which are light (under 124gr.).

In comparison with the lighter bullet and a slower powder I can rise the charge and gain more gas this way.

Like I said, I´m having A# No.2 and VV N350 right here and have no other use for it.

So I will take a look on this powders.

How long can I set out the bullets in a 9mm Truebore?

I suppose it has a long chamber, hasn´t it?

[kneelingatlas]

Keep in mind he still needs to make minimum PF for minor PF 125 .

Good point

my Pew Pew rounds are under 100pf

[Tino2212]

jayjay1 my OAL is 30 mm and i have a trubore barrel so you can go pretty long( try it yourself in the barrel you use not all of them are the same) N350 is a good powder choice but in my buddy`s gun 3n37 seems to be a little flatter with minor loads, in 9 major i prefer n350 .

yes you can use H&N plated bullets i know of a few guys here(holland) that are using them even in 9 major .

[Jaxshooter]

I have had very good luck loading 9 major with the following powders;

Silhouette

True Blue

Auto Comp

All generate plenty of gas to work the comp. My OAL is 1.160, using MG 121 gr IFP. All are loaded to 170 PF.

[jayjay1]

@all:

Thanks a bunch guys!

I think I got the idea.

Will work up some loads and see what happens.

@Tino:

Thank you for your datas.

Sure I have to see which OAL is possible in the chamber / magazine.

On the other hand, this might be no problem with lighter (and shorter) bullets.

So if the N350 works, the A# No.5 should do too.

Thanks to all of you for your support!