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View Full Version : Problems loading Lee TL-356-TC-124 with Red Dot



fireflyfather
06-21-2008, 03:54 AM
OK, long story:

God .356 TC-TL-124 mold from LEE. It casts at .359 w/ AC WW. Bought a .356 sizer, and got .357 bullets out of it (GRRRRR....)

I've checked the Lee and Alliant websites for load data using Red Dot (I only use Red Dot & Promo). The load is 4.3-4.5 grains, with a minimum OAL of 1.15". The problem here is that those loads appear extremely long to me (half the lube grooves are visible), and they will not chamber in my friend's CZ-P01. I can see two possible issues:

1. The rounds are simply too long for this bullet style and need to be seated deeper.
Solution: Load at say, 4.0 grains and 1.10"? Would that be safe?

2. The rounds are too large in diameter at .357 (unlikely, right?), and won't chamber.

The first round I tried pushed the bullet back about 0.05" (pushed all the lube grooves back into the case), and bound up the gun entirely (had to disassemble to get the round out). Needless to say, I pulled that bullet and scavenged the powder/lead. There were no noticeable signs of engraving on the rifling. Since the 9mm headspaces on the rim, could the fatter bullets be getting in the way? I'm really not sure what the solution is here. I'm guessing that I need to seat deeper and reduce the charge, but how much?

Other rounds would not chamber either. The rounds were about the same length (1.15") as factory (albeit 115 grain blazer brass JRN) rounds I had to compare against, though the one that we got out of the gun was much shorter.

Thoughts, ideas, solutions?

Bass Ackward
06-21-2008, 06:46 AM
OK, long story: I'm guessing that I need to seat deeper and reduce the charge, but how much?

Thoughts, ideas, solutions?


Could be many things. And you are right, you are guessing. Professor Gun is telling you this.

You need to slug the gun chamber area. Then do the math from what you measure.

Once you know how big and how long, adjust your load by starting low and working up.

If you do what I just described, you can change bullet designs at will with only minor adjustment. If you continue to guess, you will never maximise performance unless you luck into a bullet design that just makes it happen. In the mean time, you will have molds scattered all over the place and be cussing everything but the right thing. Everything will always be a compromise.

Once you can see the slug you took out, good chance it is even going to show you what bullet design you should be shooting or not trying to shoot. This should be kept where you know where it is as long as you own the gun. In fact, if you keep the gun through out the life cycle of it, then you may want to do this again every 25,000 rounds or so as things will change slightly over time. I keep mine with my dummy cartridges I use to set up the dies as an example. And it works for jacketed too.

But to be honest, we can't tell from this. We would simply be .... guessing.

And as to sizing, the harder the alloy, the more spring back will occur. The farther that you have to size down any alloy, the more spring back will occur. But what size sizer does your slug tell you should be using for that design anyway?

Ricochet
06-21-2008, 12:34 PM
First thing I did was to measure the maximum overall length I could load them to in MY pistols by marking a rod inserted from the muzzle to the breech face, inserting a boolit till the rifling stopped it and marking the rod inserted to touch the boolit nose, then measuring the difference. I've got to seat them till the cone starts right at the case mouth, as you'd expect. The published loads are for round nose boolits. The TC style seats a little deeper and may not work up to as high a load. Start with the starting loads, work up, and see what your chrony's showing compared to published data, watching for pressure signs.

38 Super Auto
06-21-2008, 01:11 PM
1. The rounds are simply too long for this bullet style and need to be seated deeper.
Solution: Load at say, 4.0 grains and 1.10"? Would that be safe?

2. The rounds are too large in diameter at .357 (unlikely, right?), and won't chamber.



Regrdless of what the load data tells you, the rounds must chamber in your barrel.

I'd suggest getting a case gage and/or remove the barrel from your rig and verify that the reloaded cartridges fit properly into the chamber. A case gage will also work - it will set a max OAL and verify that the bullet case combination will work.

If you have to seat deeper, back off the charge a few tenths and work your load up to optimize your accuracy.

It doesn't sound kosher that your boolits would have exposed lube grooves when loaded to "spec". I think your data is not right or maybe you are misinterpreting it.

1) The round must fit mechanically into your gun. The round must be such that your ammo chambers reliably

2) The case/bullet weight/diameter/powder charge/primer combination must give you safe operating pressure and adequate pressure to cycle your action (if you are shooting an autoloader)

3) The cartridge OAL/bullet/charge must combine to give you acceptable accuracy and a pleasing boom.

Your load data is a guide. Even if you have the same powder/primer, and case specified by the load data, you DON'T have the barrel/universal receiver for which the data was developed. So proceed, understanding that, the performance and safety of the rounds is in your hands. Be safe.

azrednek
06-21-2008, 04:53 PM
I know this is a cop-out!! I resolved the issues I had with 9MM loaded with cast bullets by using the Lee Factory Crimp die and a WD-40 soaked rag to wipe of the tumble lube off of the cartridge's nose. It is a cop-out simply because I never did determine the cause, just know what fixed it. I had the same problems with cast bullets from two different Lee molds and no issues with FMJ bullets. Bullets were being sized to .356 I think, it has been apx 10 years since I loaded any 9MM.

fireflyfather
06-21-2008, 05:03 PM
Thanks for pretty much confirming what I was thinking. This is the first time I've reloaded for an autoloader (I usually do wheel & bolt guns).

I don't have the weapon handy (It belongs to a friend who I'm trying to get into reloading/casting), but next time he is around, we'll work on getting the OAL right. I just wanted to make sure how far I should back off on the charge. So, if max load is 4.5, and Lee states 4.3 as starting, I'm guessing that 4.0 is probably a safe place to start. I know it's a little lower than the listed starting load for Lee (Alliant says reduce 10% off of 4.5 grains), but I can't see going a smidgen under with a fast powder in a small case being a problem.

Thanks.

Edited to add:



It doesn't sound kosher that your boolits would have exposed lube grooves when loaded to "spec". I think your data is not right or maybe you are misinterpreting it.

As has been said, I'm using a TC style bullet, and the load data is probably developed from LRN or similar bullet. The different bullet geometry is messing with the OAL. That's almost certainly why the lube grooves are showing and the rounds aren't seating properly. I'm going to seat them deeper until they chamber or they seat below the rim, and with a reduced charge.

Ricochet
06-21-2008, 09:21 PM
You've got it figured out. :-D

9.3X62AL
06-22-2008, 12:16 AM
The Lee TC design with conventional lube groove (not TL) in 9mm, 40 S&W, 10mm, and 45 ACP work best with about .025"-.030" of front drive band exposed above the case mouth.