180gr. FP .40S&W ??

[xobelkcat]

I'm getting ready to load my first .40's... And I have some questions that couldn't be answered through my research.

First off, I'm using Barry's plated 180gr RNFP .400 projectiles, mixed brass, and Alliant Unique powder @ 1.130 O.A.L. I'm starting @ 4.8gr and working up to 5.8gr for now.

When I made my dummy round to plunk test, I noticed there's not much room left for powder. But Speer, Alliant, Lee, and every other book, guide or manual I've seen for that matter, don't show it as a compressed charge?! And their weights are north of 6.0gr! Do any of yall use this combo? Have any issues?

Also, I've read that the .40 is more prone to KB, myth? Do I need to separate brass? Run them through a bulge buster? I'm just making inexpensive plinking ammo. Not using this ammo for compitition.

 

[The_Shadow]

I run all of my brass through the pass through sizing operation. This provides two things, another chance to inspect the cases and it sizes the cases to properly fit the tightest of chambers reliably. I use the LEE FCD with the guts removed for pass through sizing of the 40S&W, 10mm, 357Sig and 9x25Dillon cases.

The KB's have real stories with the 40's, from poor chamber support, poor lockup and RSA, leaded bores increasing pressures, bad casings to start with, to serious over loaded cartridges. Separation can help, but have a look inside to see if the are made differently. What out for PPU brass.

Your loading should be good out to 6.4 grains of Unique even with the JHP's. For reliability you might want the load at 1.1250", the only loads I have seen at 1.130 were with 190 and 200 grain bullets for the extra case capacity. Here is a copy of Alliant 2006 loading pamphlet. Best of luck!

 

[xobelkcat]

My factory G23 barrel fits the 1.130 OAL just fine.

Even @ 5.0gr, I'm still going to compress the powder charge when set to 1.130.

If I go down to the recommended 1.125" I'm going to compress to charge even more.
But, I don't see it called a compressed charge in any load data.

 

[mikepizz]

I load a180 gr lead bullet with 5gr of unique and get a 168-170 PF out of a Sti edge.

 

[xobelkcat]

I load a180 gr lead bullet with 5gr of unique and get a 168-170 PF out of a Sti edge.

What OAL? What velocity are you getting? I'm not familiar with power factors.

 

[xobelkcat]

Does anyone have any idea why this charge is going to be compressed when no data shows a compressed charge?

 

[xobelkcat]

Does anyone have any idea why this charge is going to be compressed when no data shows a compressed charge?

^^^This

 

[The_Shadow]

Many pistol powder charges are slightly compressed, it is because of the case capacity being small and the bullets being long. Being slightly compressed shouldn't be a problem, Alliant Unique powder is fluffy so you need to stuff it so to speak. It will be fine.

 

[davidd]

I had the same concerns recently using VV N340 for the first time with 9mm loads. The starting load was so high up the case that it had to be compressed. However function was fine with no signs of case stress. I have not loading anthing yet past the starting load.