The Firing Line Forums - View Single Post - Some full-power 9x19 data (124/VV-3N37)

Clark · September 25, 2002, 10:36 AM

Smithz,
I have overloaded 30 calibers in 1000 load work ups to see what happens.

Based on my 115 gr and 147 gr overload notes*, I would suspect a feed ramp case bulge with 124 gr bullets and 3N37 at about [don't try it] ~~ 9.6 gr~~ [don't try it].
You only got up to 7.4 gr.

I would hate to imagine anyone who can't spot the pressure signs working up these loads. They are not idiot proof at all. All the baloney in load books about approach with care is actually true for these. I learned the hard way about feed ramp case bulges. Only .7 gr more powder and blam, a hole in the case. Only .3 gr more and the whole case head comes off and blows up the extractor, hold open, and magazine floor plate. Also some brass debris can come back through the ejector slot in the slide and hit the shooter in the face. The bloody spectacle is called "Major face". Once I leaned this on 9x19, I have only worked up till I see the tiny little smiley faced bulge on the case from the feed ramp. Then I reduce the loads by a reasonable safety margin. Maybe not the load book safety margin [which can be as high as 250%] but at least 6% below the feed ramp case bulge for carry loads. I have avoided trouble this way in 10mm, 25acp, 32acp, 380, 9x23, 357 Sig, 40sw, and 45acp. In overloading non feed ramp cartridges I look for other signs in the brass: 32sw, 32Colt, 38sp, 38sw, 45 long Colt, .410, 7.62x54R, 8x57mmJS, .243, and 45/70. Some guns are not as strong as the brass, and the gun fails.

*With a Kel-Tec P11 9x19mm pistol [just about the same terrible .190" of feed ramp intrusion into the case support as a Glock 19] I worked up the max loads with 1.169" OAL and RP primed brass.

In the case of this 40sw feed ramp, when I welded it up and re cut the chamber and feed ramp, the threshold of kaboom went from 26% overload to over 68%. CASE SUPPORT IS A FIRST ORDER VARIABLE!
http://glocktalk.com/attachment.php?s=&postid=662131
http://glocktalk.com/attachment.php?s=&postid=663556

There is also the question of what is an overload.
The "VV1" book is hotter in the 9mm than "VV3". There are different loads of 9x21 that have a longer over all length, but are still short enough to fit in a 9x19 magazine.

Hornady 147 gr HPBT XTP
Vihtavuori 1st edition:9x19mm 4" barrel, 147 gr, 1.142", 6.1 gr 3N37, 1152 fps 36.3kpsi
Vihtavuori 1st edition:9x19mm 4" barrel, 147 gr, 1.142", 5.7 gr 3N37, 1140 fps 36.3kpsi
Vihtavuori 1st edition:9x21mm 4" barrel, 147 gr, 1.161", 6.6 gr 3N37, 1227 fps 42.8kpsi
Vihtavuori 3rd edition:9x19mm 4" barrel, 147 gr, 1.142", 5.2 gr 3N37, 1066 fps max
Vihtavuori 3rd edition:9x21mm 4" barrel, 147 gr, 1.161", 5.5 gr 3N37, 1120 fps max

September 25, 2002, 10:36 AM	#10
Clark Senior Member Join Date: December 4, 1999 Location: WA, the ever blue state Posts: 4,678	Smithz, I have overloaded 30 calibers in 1000 load work ups to see what happens. Based on my 115 gr and 147 gr overload notes, I would suspect a feed ramp case bulge with 124 gr bullets and 3N37 at about [don't try it] ~~ 9.6 gr~~ [don't try it]. You only got up to 7.4 gr. I would hate to imagine anyone who can't spot the pressure signs working up these loads. They are not idiot proof at all. All the baloney in load books about approach with care is actually true for these. I learned the hard way about feed ramp case bulges. Only .7 gr more powder and blam, a hole in the case. Only .3 gr more and the whole case head comes off and blows up the extractor, hold open, and magazine floor plate. Also some brass debris can come back through the ejector slot in the slide and hit the shooter in the face. The bloody spectacle is called "Major face". Once I leaned this on 9x19, I have only worked up till I see the tiny little smiley faced bulge on the case from the feed ramp. Then I reduce the loads by a reasonable safety margin. Maybe not the load book safety margin [which can be as high as 250%] but at least 6% below the feed ramp case bulge for carry loads. I have avoided trouble this way in 10mm, 25acp, 32acp, 380, 9x23, 357 Sig, 40sw, and 45acp. In overloading non feed ramp cartridges I look for other signs in the brass: 32sw, 32Colt, 38sp, 38sw, 45 long Colt, .410, 7.62x54R, 8x57mmJS, .243, and 45/70. Some guns are not as strong as the brass, and the gun fails. With a Kel-Tec P11 9x19mm pistol [just about the same terrible .190" of feed ramp intrusion into the case support as a Glock 19] I worked up the max loads with 1.169" OAL and RP primed brass. In the case of this 40sw feed ramp, when I welded it up and re cut the chamber and feed ramp, the threshold of kaboom went from 26% overload to over 68%. CASE SUPPORT IS A FIRST ORDER VARIABLE! http://glocktalk.com/attachment.php?s=&postid=662131 http://glocktalk.com/attachment.php?s=&postid=663556 There is also the question of what is an overload. The "VV1" book is hotter in the 9mm than "VV3". There are different loads of 9x21 that have a longer over all length, but are still short enough to fit in a 9x19 magazine. Hornady 147 gr HPBT XTP Vihtavuori 1st edition:9x19mm 4" barrel, 147 gr, 1.142", 6.1 gr 3N37, 1152 fps 36.3kpsi Vihtavuori 1st edition:9x19mm 4" barrel, 147 gr, 1.142", 5.7 gr 3N37, 1140 fps 36.3kpsi Vihtavuori 1st edition:9x21mm 4" barrel, 147 gr, 1.161", 6.6 gr 3N37, 1227 fps 42.8kpsi Vihtavuori 3rd edition:9x19mm 4" barrel, 147 gr, 1.142", 5.2 gr 3N37, 1066 fps max Vihtavuori 3rd edition:9x21mm 4" barrel, 147 gr, 1.161", 5.5 gr 3N37, 1120 fps max