Please help with Hodgdon Longshot powder loads for Lee 9mm and .40 cast boolits

[mojomandan]

Hello guys,

I have cast the following boolits with my Lee 6-cavity molds:

TL356-124-2r 9mm

and

TL401-175-SWC .40 S&W

I would like to develop loads using Hodgdon Longshot since I have a nice amount of it, and it is supposed to generate higher velocity with lower pressure than other powders. Here is my quandary:

When looking at the Hodgdon reloading data center, they have data for the following 9mm bullets:

http://www.hodgdonreloading.com/data/pistol

125Gr. HDY HAP
125 GR. SIE FMJ
125 GR. LCN

The data vary considerably in pressure and velocity for the above bullets despite their identical weight...you can see that a safe load for one bullet would result in overpressure for another bullet. How do I know how to reload my Lee cast boolit safely with Longshot?

The Hodgdon reloading data center also has the following .40 S&W bullets matched to Hodgdon powder loads:

180 GR. BERB FP
180 GR. HDY XTP

There is some variability in pressures between the two bullets here as well.

I chose the above bullets since they were close in weight to my cast ones. Does anyone have advice on how to safely proceed on the above?

Thank you!

[lar45]

Looking at the 9mm data, the first thing that jumps out is the COL (Cartridge Overall Length) is different for the 3 bullets in question. Having the bullet seated out farther increases the effective case volume, which means that you can load more powder safely and get higher velocities.

The 40 S&W had the same COL, but the bullet lengths may be different. If one of the bullets is longer than the other, then the effective case capacity is reduced which means that you'll have to use a slightly smaller powder charge to keep in the safe pressure range.

A Chronograph is a great tool for working up loads where the data may not be very clear. If you are loading X grains of Longshot expecting to get 1150 fps and your actual velocity is higher, then you can assume that the pressure is higher than expected also.

If you post your loaded length of the 9mm and 40 loads, then I'd be more than happy to run it through Quickload to get an idea of safe max loads with Longshot. http://www.neconos.com/index.html

I hope this helps some.

[MrBFR]

Use their 165gr plated data, shows from 6.9gr (1090 fps) to 7.8gr (1200 fps), but back off a few tenths. I love Longshot and also have a lot of it, and depending on whether you're wanting a plinking round or something higher end for woods use, it's a good powder either way and can be very accurate and consistent.

If I were you I'd start out at around 6.0gr and go from there. I have some Longshot 170gr cast .40 data, but it's on the warm side (1250 fps 4", 1450 fps 6"!) but it can work well too at lower speeds.

[petroid]

FWIW I use Longshot with the Lee TL401-175-SWC with 6.5gr Longshot at a COL of 1.125" in my 3" XD. Chrono matches WWB. For a lighter load I use 5.0gr at about 800 fps but the cases come out sooty. Longshot likes to be loaded pretty warm but with my 3" barrel the velocities are lower than published. Haven't tried it in 9mm

[gray wolf]

Just start low and work up while keeping in mind it burns a little dirty at the low end.

[mojomandan]

Guys,

I appreciate your knowledgeable input.

Gray Wolf,

How do I know when I have reached a maximum tolerable pressure load?

[gray wolf]

Well my answer --and not being a wise guy -- would be for you to really do some reading.
Your load books would be a good place to start. Your question is one with an answer you should know before your finger ever gets into the trigger guard, so you don't get into trouble. With your knowledge base ( again not being smart ) you should be loading directly from a book with book listed components.

Every time you pull a trigger you are dropping the hammer on a potential bomb that you hold in your hand 30 inches away from your face.

If someone else wants to describe the whole process, and it's much more involved than a flattened primer. They can help you, my advise is to do some research.

[mojomandan]

Gray Wolf,

Your warnings are well-taken. I have done my fair share of reading online articles and my books on reloading (Hornady manual that came with my Lock-n-Load Classic kit, Lyman Cast Bullet Handbook, etc), and have read about many possible signs of overpressure, but there always seems to be exceptions to many of these rules.

So, while I am fully acclimated to how factory load recoil feels and how spent cases look from my pistols, I also do know that things like excessive recoil, flattened/extruded primers, and various types of case head deformation are classic signs of overpressure.

But, like I said, I often read that the above are not absolutes (ie, Federal primers have thinner metal in their cups, so flattened primers may occur without overpressure).

So, I asked because I like to hear from other people and gather as much info as possible. I am no expert, but I do follow protocol and available recipes.

[lar45]

A chronograph is a great tool to use when working up loads on unknown stuff. Velocity isn't free, it comes with more powder burnt or more pressure.
From looking at Hodgdon's site it looks like a 180xtp with 8gns of Longshot should give about 1160fps at 32,300psi.
Your 175SWC is a little lighter so that should lower the pressure a little, it is also a cast bullet so that should lower the pressure a little more.
Saami max for the 40S&W is 35k psi, so you should be able to push it a little more and stay safe, but there isn't any easy way to tell when you reach 35k. If you get flattened primers then you are probably way too hot.
So what do you do? Sometimes it's a best guess and see what happens. That's where the chronograph comes in, if your velocity is higher than you're expecting, then your pressure is probably higher also.

I like Quickload, it is great for looking at what ifs for unknown combinations of bullets and powders.
I plugged the 175SWC loaded to 1.125" in the 40S&W into Quickload with Longshot and for a 5" bbl 8.3gns should give around 1200fps at just under 35k psi.
Quickload is not load data, it is just a computer simulation and should be double checked against regular load data.
So we back off of the theoretical max of 8.3gns to maybe 7.5gns, and load some in .1gn increments, checking the velocities on the chronograph and when we get to 1200fps then that should probably be the max load.

With all of that said, if you are pushing higher velocities than what a standard load would be, then you probably have a higher slide velocity also. So if we don't want to beat the gun to death, it may need a stiffer recoil spring.

Everybody feel free to jump in if I have made an error somewhere along the way.

[mojomandan]

Lar45, thank you for the in-depth response. I have taken your advice and made use of a chronograph...the Competition Electronics Prochrono.

Here are some findings:

I loaded 5.4, 5.6, and 5.8 grains of Longshot behind my Lee 9mm boolits which dropped at 122 grains. I used a Glock 26 with 4.0" Lone Wolf barrel, and fired round after round of reloaded 9mm, but got nothing but "Error" on the chrono screen, therefore thinking my chrono was broken. Anyway, I continued to fire all 9mm rounds, starting with two factory rounds, followed by 4 rounds with 5.2 grains, 4 rounds with 5.6 grain, and 4 rounds with 5.8 grains. I checked each spent case for signs of overpressure, but saw none. Recoil was a bit more pronounced at 5.8 grains.

Once "cease fire" was called, a range officer suggested using the chrono sun shields, despite an overcast sky. I did not bring them, but cut strips of paper to use as shields and taped them to the wire aiming guides. With no more 9mm, I switched to my .40 Glock 27 with 4.49" Lone Wolf barrel. Starting off with four factory .40 rounds, I started getting readings!

I then proceeded to shoot 5 rounds with 6.8 grains of Longshot, followed by 4 rounds of 7.3 grains of Longshot. My Lee .40 bullets dropped at 176 grains. I could not differentiate recoil between the factory loads or any of my own, there were no overpressure signs on cases, but velocity was different:

Factory: 1090, 1075, 1096, 1074 fps
Lee boolits with 6.8 grains Longshot: 1128, 1143, 1125, 1130, and 1102 fps
Lee boolits with 7.3 grains Longshot: 1147, 1157, 1150, 1141 fps

The 7.3 grain load produced velocity on target with published data of 7.5 grains Longshot and a 180 grain BERB FP bullet (dunno what that is!). So, 7.3 grains will be my upper limit.

Next week, I will once again try the 9mm loads to see how they do and report back.

[lar45]

Excellent, the 7.3gn load should be perfectly safe.
It looks like you are on the right track with your 9mm loads also.

Glenn.