9mm Presure in my Norinco

[lead Foot]

Been making cast and loading lead boolits in many calibre's for a long time now. I did'nt know what I was up against when I bought my new Norinco 1911 9mm. I have the RCBS 09-124-CN. I was getting a lot pressure under starting load. First I sluged the barrel @ .357. The boolit engaged the lands with an OAL of 1.030 and sized to .356 ~ less with .358. I was getting a lot of leading at this stage. Next I had the throat cut to an OAL of 1.113, touching the lands. Next I sized to .358 and loaded at OAL 1.111. I loaded a few rounds at the starting load. 5grs of AP100. The results were stunning. First no leading at all, accuracy was very good ~1'' to 2" @ 25 meters. But the rub is it is near max. The ADI handloaders guide says the starting load is 5grs AP100 @ 890fps and the max is 6.2grs @ 1100fps. The 5grs AP100 gives me 1138fps. Can anyone tell me why the presure is still high. I've come to a dead end:-?.
Thanks Lead foot;

[MtGun44]

I don't see the problem. Your gun has given you the gift of producing good velocities,
good accy and no leading - with the use of less powder. What a deal! Do you complain
if you vehicle gives you too good of gas mileage? This barrel is being very efficient at
turning powder into velocity. How is this a problem?

Tight chambers can produce higher pressures, the rifling looks kinda deep, but in the end,
I just know that some barrels produce higher pressures than others, which is why there
is a starting load.

Relax and enjoy your great load. I have had excellent results with this same boolit in my
9mms. Do you happen to know if Hodgdon imports AP100 and if so what it is called here?
Maybe Universal Clays? Guessing from the charges that you list.

Good looking boolits, by the way.

Also, some are tearing their hair out trying to get what you have right now. You are doing
real well on this one.
Bill

[63 Shiloh]

G'Day Leadfoot,

Mate, AP100/ HS-6 is a bit too slow for the 9mm in my experience.

I have the same mold and size to .357", lube with White Label CR Red, OAL: 1.095", and 3.6gn of AP70N/ Universal.

The AP70N/ Universal is a great powder for the 9mm, AP50N/ HP-38 will work well too, it does flip the barrel a bit too much for my liking though.

What pound recoil spring are you running? I have used a 12lb in my CZ75 and lowered my charge to 3.2gn of AP70N, very accurate with quick target acquisition.

Good luck mate :castmine:

Mike

[HeavyMetal]

My question is how do you know pressure is high?

Curious as to how you determined this.

[MtGun44]

My assumption is that because the velocity is much higher than book velocity, the pressure
must be "high". But, so what? If the starting load makes higher than book velocity, but
is in the normal range, seems like a win to me.

Bill

[GREENCOUNTYPETE]

don't books assume 4 inch barrel for a 9mm and a 1911 might well have a 5 or 5.25 inch barrel that would creat more speed

i recall reading that barrel lenght has a great effect on speed in pistols sometimes a 100 or more feet per second per inch till somewere around 7-10 inches depending on powder

the longer barrel with the slower powder may give even greater increase as preasure may peak near the end of the barrel.

perfect efficincy is actualy to have it peak just before the end of the barrel, is my understanding , i see data showing rifles peaking preasure 4-12 inches down the barrel , Larry had some data on lever revolution showing it peaked further down the barrel than his earlier tested powders


another idea what is the temp at the range like is it warm to hot that affects some powders

[lead Foot]

Thanks Bill. I'm very happy with it and get great scores. The primers are flaterned a lot. The close'st to AP100 acording to my powder equivalent chart is IMR 4756 and in between Vihtavuri N340 and 3N37. 63 Shiloh ADI did make a AP90 for the 9mm. They improved it and called it AP100. Interesting you mention muzzle flip, In this case it is perfect for me. I don't get any accuarcy unless it is near max. Had no luck with AP50 and AP70. Will post a pic of primers later. Dose the main spring make a difference ~ mine very is heavy and dos'nt lock back when empty.
Lead foot.

[lead Foot]

don't books assume 4 inch barrel for a 9mm and a 1911 might well have a 5 or 5.25 inch barrel that would creat more speed

i recall reading that barrel lenght has a great effect on speed in pistols sometimes a 100 or more feet per second per inch till somewere around 7-10 inches depending on powder

the longer barrel with the slower powder may give even greater increase as preasure may peak near the end of the barrel.

perfect efficincy is actualy to have it peak just before the end of the barrel, is my understanding , i see data showing rifles peaking preasure 4-12 inches down the barrel , Larry had some data on lever revolution showing it peaked further down the barrel than his earlier tested powders


another idea what is the temp at the range like is it warm to hot that affects some powders

Good point ~ the ADI handloaders guide is pretty plane No OAL but did list a 4" barrel.

[Ausglock]

G'day. Lead Foot.
I run 5.0gr AP-100 with a lee 125rn in a G34 with a stormlake barrel. Nice accurate load and functions fine.

4.2gr AP-70 does the same velocity and group size. POA is the same too.

[lead Foot]

Here's a pic of the fired case's. They are winchester (WSP) Feds fattern right out ~ thats a shame, I have 7,000 of them. Hi Ausglock. What part of this land do you live.

[noylj]

Your gun is a perfect example of why you always start at a starting load. Also, you can drop the charge down.
This is a stupid question but--have you weighed your bullets?
If you really are unhappy, you can get a custom barrel.

[lead Foot]

Your gun is a perfect example of why you always start at a starting load. Also, you can drop the charge down.
This is a stupid question but--have you weighed your bullets?
If you really are unhappy, you can get a custom barrel.

Yes it was a wake up call for me. The longer you have been reloading the more careful you should be. Very conscious of the weight of my boolits. They weigh in at 124.4grs to 125.2 (lubed) RCBS 09-124CN. 90% lino 8% pure 2% tin ~ Real hard.
I'm more than happy. In the military comp last week I put six shots in 2" off hand at 25 meters. Also makes perfect holes at all ranges. :bigsmyl2:

[Ausglock]

LF.
I'm in NSW.

What lube you using?

I have been using Whitelabel BAC with good results.

[lead Foot]

LF.
I'm in NSW.

What lube you using?

I have been using Whitelabel BAC with good results.

Hi Ausgock, You guys got lucky in the state of origin the other night. I use Felix lube.

[MtGun44]

Those primers look fine to me. Accurate, no leading, normal full power velocity, I'd call it
a good load, just not at the expected powder charge. You have a "low fuel consumption
pistol" ;-)

If not locking back, may actually need a touch more powder to get it to push the slide back
a bit more, assuming notch and lock pieces not worn and mag springs up to snuff.

Bill

[lead Foot]

Those primers look fine to me. Accurate, no leading, normal full power velocity, I'd call it
a good load, just not at the expected powder charge. You have a "low fuel consumption
pistol" ;-)

If not locking back, may actually need a touch more powder to get it to push the slide back
a bit more, assuming notch and lock pieces not worn and mag springs up to snuff.

Bill

Thanks bill the gun is brand new. I no you guys in the US can't buy 'em now ~ made in China from good ole aussie steel.:-P

[Ausglock]

Hi Ausgock, You guys got lucky in the state of origin the other night. I use Felix lube.


Pure skill from the blues :mrgreen:

Where do you get felix lube?
does it need heat to run through a Lyman 450?
Thanks.

[lead Foot]

Made the felix lube myself. You can make it soft or hard, your pleasure. I have the RCBS lam 11 lube sizer. Works good for me. I use it in rifle and pistol.
Here's the recipe.
http://castboolits.gunloads.com/showthread.php?t=543