Problems loading 9mm berry's 124 flatnose

[74A95]

If anyone can tell me if going .050 deeper is safe, I may work the length down, but if they feed and cycle there won't be a need.

Yes, it's safe. But you have to reduce the powder charge to keep the chamber pressure the same.

Here's the deal with OAL. You can seat any bullet to any OAL as long as:

1) It fits in the chamber.
2) It fits in the magazine.
3) It feeds reliably.

If you seat the bullet deeper that what is listed for that bullet in a loading manual, you must reduce the powder charge to keep the pressure the same.

Seating the bullet deep does increase pressure in a handgun cartridge because there is little space to work with, so you must be cautious and mindful of powder charge weight.

 

[Aguila Blanca]

I have to apologize for my post #18. In post #14, you wrote "Universal" for the powder. I somehow registered that as "Unique," which is why in post #18 I was blathering about Unique.

Universal is made (or sold) by Hodgdon, so my first resource would always be the Hodgdon web site, which we can probably assume will be reasonably up to date. They list a load for a 124-grain Berry's bullet -- but it's a hollow-base round-nose bullet. They show it loaded to a C.O.A.L. of 1.150" but that's not helpful because of the hollow base.

1.150" is the C.O.A.L. suggested by Berry's for that bullet. the bullet itself has a length of 0.612". The 9mm case has a nominal length of .754". This tells us that the seating depth for that combination is 0.216".

Awhile back, in another thread, I proposed approaching situations like yours using a greatly simplified analysis from high school physics -- applying the formula for behavior of gasses: P1V1/T1 = P2V2/T2. We want to solve for the unknown pressure, P2.

The [nominal] usable case volume for a 9mm is 0.862 cubic cm (according to Wikipedia). That converts to 0.0526 cubic inches.

If we use a cross-sectional diameter of.356" (which has to be an approximation, because the case tapers), we get a cross-sectional area of .0995 square inches. Multiply that by your .211" seating depth and the volume occupied by the bullet is .0210 cubic inches. Subtract that from the nominal case volume and that leaves a usable volume of .0316 cubic inches.

Now run the same calculation with a seating depth of .25". The volume occupied by the bullet then becomes .0249. That leaves .0277 cubic inches of usable case volume. That's a decrease of 12.34 percent. So a very crude approximation is that the pressure will increase by roughly 12 percent.

For the one load that Hodgdon has data for using Universal and a 124-grain bullet, their starting pressure is 26,300 psi. Increasing that by 12.34 percent yields 29,545 psi. Hodgdon's maximum load for that recipe is 33,500 psi, so it doesn't appear that the increased seating depth would put you over the maximum pressure. Nonetheless, reducing the starting load from 3.8 grains to 3.5 grains would certainly be prudent.

CAUTION: As Unclenick pointed out in the thread where I proposed this analysis, it is at best a crude approximation. I'm comfortable using it for myself because I never (with one exception) go much higher than mid-range loads. A much better approach would be to use QuickLoad or Gordon's Reloading Tool. I have submitted the dimensional data for all of Lee's .45 ACP and 9mm bullets (except the hollow-base bullets, because I don't have dimensions for the 9mm hollows) to Gordon's Reloading Tool but, as of a week ago, they haven't issued an update with that data included. Hopefully it will be in the next update.

 

[Double K]

That cartridge on the right looks way to long for a 9mm, does it even fit in the magazine? Mine look just like the one on the left.

As far as loads go pick an appropriate powder and load 5 with the starting load, go up in 3 tenths of a grain increments chronographing the loads, let the chronograph tell you when your approaching maximum or whatever your desired velocity.
I like 4.0gr. of universal with that bullet, it's right around 1000fps, cycles my 19 everytime and stays on a 8" plate at 50yds easily.

 

[Aguila Blanca]

As far as loads go pick an appropriate powder and load 5 with the starting load, go up in 3 tenths of a grain increments chronographing the loads, let the chronograph tell you when your approaching maximum or whatever your desired velocity.
I like 4.0gr. of universal with that bullet, it's right around 1000fps, cycles my 19 everytime and stays on a 8" plate at 50yds easily.

What do you use for a C.O.A.L.?

 

[Unclenick]

The reason the ideal gas law doesn't really work to predict pressure in this instance is it assumes the gas quantity is in equal amounts at the pressure peak and at the same temperature in both instances. But pressure goes up exponentially with a reduction in powder space because the higher start pressure in the shorter space causes the powder to burn faster so there is more, hotter gas at the peak for the shorter COL. In this instance, QuickLOAD shows the pressure increase at about +35%.

It should be noted, however, it is not uncommon for primers to unseat bullets in the short cartridges before the powder gets fully burning. If this is happening for your load, then the real volumes are not as QuickLOAD or GRT would predict them, as they assume reaching start pressure before the bullet starts to move. How to know that it is happening is trickier. In the .22 Hornet, which is famous for this problem, high velocity SD and discouraging accuracy are reported, and going to a mild (often standard pistol) primer will tend to cure it. In a handgun, the high velocity SD may be apparent, but without rifle accuracy, the change in group spread is not normally discernable. About the only other clue you get is your change in mean velocity is a lower percentage than the interior ballistics software predicts.

 

[kmw1954]

Western Powders has data listed for each powder in 9mm using either the Berry's RN flat base or the HBFP.

I have also had discussions with many reloaders about the Berry's Hollow Base and the Flat Base. From everyone I have talked with it is generally agreed that even though the Hollow Base is over-all longer they still displace the same volume inside the case.

Western suggests a length of 1.060" for the HBFP.

I use the 1.055" length for both my FB and HB loading because I need that to plunk my XD..

 

[Double K]

What do you use for a C.O.A.L.?

Honestly I've never measured them, all my pistols are semi-auto's, I remove the barrel from the gun when setting up the dies for my Dillon and check how the ammunition drops into the chamber adjusting both the depth and crimp.
How the ammunition fits in the gun you're shooting it in is the deciding factor on such adjustments to your dies. Individual chamber, case, bullet and die dimensions all effect how a reloader sets his dies.
There's to many variables in the equation to give exact measurement to someone else with assurance it will work for them.

 

[Aguila Blanca]

What do you use for a C.O.A.L.?

Honestly I've never measured them, all my pistols are semi-auto's, I remove the barrel from the gun when setting up the dies for my Dillon and check how the ammunition drops into the chamber adjusting both the depth and crimp.

But you offered a charge weight and a velocity. That's useless without knowing what you use for the C.O.A.L.

How the ammunition fits in the gun you're shooting it in is the deciding factor on such adjustments to your dies. Individual chamber, case, bullet and die dimensions all effect how a reloader sets his dies.

How the ammunition fits a particular gun is not a deciding factor for me. I have three 1911s in carry rotation, and several others that see recreational and/or competition use. It would be silly for me to tune my ammunition to just one of them, since that could exclude several others. I need my ammunition to fire through any gun I put it in. If that results in a bit of extra bullet jump in some of them ... so be it.

 

[Double K]

But you offered a charge weight and a velocity. That's useless without knowing what you use for the C.O.A.L.


How the ammunition fits a particular gun is not a deciding factor for me. I have three 1911s in carry rotation, and several others that see recreational and/or competition use. It would be silly for me to tune my ammunition to just one of them, since that could exclude several others. I need my ammunition to fire through any gun I put it in. If that results in a bit of extra bullet jump in some of them ... so be it.

For some reason many people don't approach loading handgun and shotgun ammunition with the same attention to detail as rifle ammunition.
There's no problem with loading one ammunition for several different firearms but your going to have to test each one individually to see if it fits in the chamber and magazine and loading them closer to starting loads would be prudent as well.
I offered 4.0gr. of universal because it's about the minimum that will cycle a 9mm 100% of the time, it happens to be about 1000fps from my gun. I wouldn't call that useless information, most reloaders are surely aware that every gun will have a different average velocity because barrel length, rifling type etc etc.
You have to get out of that mindset that loading for a handgun is different than loading for a rifle.