Best practice for loading Lee 356 124 TR for 9mm

  • Last Post 4 hours ago
John Alexander posted this 3 weeks ago

What is the best bullet diameter and hardness for the above bullet for use in 9mm autoloader.  

What else may help?


Attached Files

Order By: Standard | Newest | Votes
max503 posted this 3 weeks ago

I shoot those unsized.

Attached Files

David Reiss CBA Membership Director posted this 3 weeks ago

I own probably about 15 or more 9 mms without counting them. They are very forgiving with accuracy as long as you use as large a bullet as possible. Most made today will feed any bullet style without issue. I've even had good success with bullets designed for .38 specials and .357s. 

You want to size bullets to the chamber size. Start with .358 and see if it will seat without bulging your case and then chamber. This requires using the right expander and the one supplied with 9mm dies might not be large enough. If this does not work, then keep stepping down .001 until they just fit and chamber without issue. 

As far as hardness, use something up to WW hardness or just less.

Smaller bullets will lead the bore so this is why you start with as large as possible. 

David Reiss - NRA Life Member & PSC Range Member Retired Police Firearms Instructor/Armorer
-Services: Wars Fought, Uprisings Quelled, Bars Emptied, Revolutions Started, Tigers Tamed, Assassinations Plotted, Women Seduced, Governments Run, Gun Appraisals, Lost Treasure Found.
- Also deal in: Land, Banjos, Nails, Firearms, Manure, Fly Swatters, Used Cars, Whisky, Racing Forms, Rare Antiquities, Lead, Used Keyboard Keys, Good Dogs, Pith Helmets & Zulu Headdresses. .

Attached Files

Little Debbie posted this 3 weeks ago

I shoot this bullet un sized after two light coats of Ben’s Tumble Lube. I use the bullet in 9mm and .38 Special with good success. (Can even shoot 2-300 rounds without lead build up in a Glock.........) I use any alloy, generally pretty soft as it comes from my bullet trap. The beauty of this design is the lack of fiddling you have to do to make it work. I prefer the lightest charge of Bullseye, W231,
A#2 that reliably cycles the action. This has worked in SIG, Glock, Ruger, Kimber, and S&W semi autos. For a couple of years I used small pistol magnum primers because they were all I had. Strangely the magnum primers gave slightly lower velocity, smaller extreme spreads, and lower SDs than exact loads with a standard primer. Truncated shape makes it feed well in everything I’ve tried it in. Bottom line you can make this bullet work well with any alloy, any fast powder, and any primer.

Attached Files

dale2242 posted this 3 weeks ago

 I size my generic #2 alloy to .358 for 9MM.

Attached Files

R. Dupraz posted this 3 weeks ago


For a Ruger LC9s. 

NOE 358-129-SWC 

WW & lino 10-12 Bhn or there abouts  drops with my alloy at 130 grains

Sized ,356"

white label lube 2500 only because I have some

Just enough Unigue to run reliably 

No leading, accurate and works

for practice only



Attached Files

John Alexander posted this 3 weeks ago

Thanks to all for the helpful advice.


Attached Files

Qc Pistolero posted this 6 days ago

My sizer is marked .356 but both my micros give me closer to .357 than what indicated.None of my 9mms or my friend's balk at them(I sell a few Ks a year).But then I must add that not one of the 9 they are used in is a plastic gun.Don't know if that it'd make a difference(I don't think it would)but I've been told Glocks might be finicky about this.

Attached Files

OU812 posted this 3 days ago

Mike Venturino of Shooting Time magazine stated that Winchester 9mm brass is thinner than most and allows for fatter bullet to chamber more easily.

Attached Files

GP Idaho posted this 4 hours ago

John:  I have several 9mm moulds in the 120-124 range.  All my nines seem to run best when the bullets are sized to just the plus side of .356 but then all my cast bullets are powder coated and I never have a problem with leading.  Gp

Attached Files