Provlem with Lee 356-120-TC and Bullseye

[Kenk4]

I am getting decent accuracy but a lot of leading when using Lee 356-120-TC over 3.8, 4.0, and 4.2 grains of A. Bullseye. The data is coming from Lyman's 4th edition cast bullet book. The bullets are sized to 0.357" and lubed with LBT Blue Soft. The alloy is air cooled clip-on W.W. with 2% added tin. The hardness is a BHN of 14 which is just below Lyman No 2. The barrel slugs out at 0.356". The leading is the worst in the first inch or so and persists in the groves the length of the barrel.

I tried Universal and got heavy leading and very poor accuracy but that was before I slugged my barrel and switched to a 0.357" sizing die.

Does anyone have any suggestions? Is the lead too soft? According to the data, bullets should be moving between 1000 and 1100 FPS.

Should I switch to a slower powder or a harder alloy? Perhaps add some Linotype?

Thank you.

[Yodogsandman]

Could you be crimping too hard, resizing the boolit down smaller? Try a .358" sizing die, too.

Are you waiting long enough for the boolits to age harden? You could try water dropping from the mold to add some BHN's to it.

[stinjie]

Maybe try 3.6 or 3.7 grains of the B/E.This load helped 2 of my lead-prone 9mm from build-up (kt pf9 and Ruger p89dc).Ben's Red lube helped also.Some guns do better than others with lead.I had a prior K/T pf9 that did not lead at all with 4.0 gr of B/E powder.My CZ 75B gets no leading at all with near max loads with that Lee bullet,using data for 124 lead bullets.Good luck,shoot safe!

[hpeach]

The same problem surfaced here some months past. The solution that worked was powder coating. Enjoy

[Dusty Bannister]

I use that bullet, that alloy (less tin), and NRA 50-50 or home made Lithi-Bee at .357" and 3.7 or 3.8 Grains of Bulls Eye. That has shot lead free in Ruger, Glock, and Marlin Camp Carbine. I never measured the group size though. Has accuracy been an issue, or are you pushing to make "major"? I have been careful with the taper crimp setting though.

[Kenk4]

I'm just trying to get it to shoot lead free. The accuracy has been acceptable. Crimp, might be a problem I will check it to see what it's doing.

[Floydster]

I powder coat this bullet for my .357 mag., 38 Super and my 9mm.
I push it hard in all these calibers with zero prob.
Also have run these with Lyman lube and with proper sizing, very little leading.
Floydster

[jcameron996]

Pull a bullet and check your size again to make sure you aren't sizing the bullet back down with the case. I ran into this and had to change out the expander plug on my Lee 9mm die to a .38 s&w. Think the plug cost like three bucks to solve the problem.

Sent from my 0PJA2 using Tapatalk

[jimb16]

I always had problems with that bullet too. I finally gave up. There are plenty of other very good bullets for the 9mm and it just wasn't worth the frustration.

[GBertolet]

I think your bullets are getting swaged during the seating/crimping operation. Most expander balls are designed for .355 jacketed bullets, which means they expand the case mouth to .352 to .353 diameter. That's a lot of squeezing for a soft .357 bullet. Be aware, also too heavy of a taper crimp will also swage a bullet down while in the case. I've been there and experienced all of these, as I have a 9mm that has a .3575 barrel. I made my own expander ball that expands my cases to .356 for my .358 bullets, which fit and function OK. Stay away from thick walled brass for this. You could likely modify a 38 special expander also to fit the 9mm die.

[Tar Heel]

I would use straight WW metal and drop-quench them to get the BHN up a tad higher. I use the NRA 50-50 formula lube and have not had any problems with the drop-quenched alloy and lube in all my 9's. I get my lube from LSStuff < http://www.lsstuff.com >

Be sure your taper crimp is properly adjusted too.

[GhostHawk]

I gave up on it and use the .358 124 grain instead. No leading, no keyholing, no patterns instead of groups.

However it will depend somewhat on how tight your barrel/chamber is.

For my Hipoint C9 the bigger bullet solved all problems.
Same for my single shot 9mm carbine.

My Hipoint 9mm carbine seems to do fine with the smaller boolit.
My buddy's Berretta 92fs had to have them sized down a touch or they would not always go into battery.

[GooseGestapo]

I've never used LBT Blue. I have used NRA 50/50 and SPG. Same boolit. I don't recommend Bullseye in 9mm.
Suggest WST, or better LongShot. Less slam easier push to start bullet.

[Kenk4]

Thank you for all of the responses. I seated a bullet and pulled it. It still measured 0.357" Then I seated and crimped a bullet, then pulled it. It measured 0.355". I'm thinking that this might be an excellent place to start.

Has anyone ever used Universal with this bullet? I have a lot of it and it works great in 44sp and 44mag.

[runfiverun]

.358..

[JeffG]

Kenk4, are you using a Lee FCD? Some people have had issue with that die. I personally never did but switched to Lee taper crimp die instead. I'm now using a Hornady taper crimp seating die and have no issue in 3 different 9mm, sized 357.

[Kenk4]

I'm using a Dillon taper crimp die on a 650 progressive press.

[btreanor]

I've had my best luck in 9mm with .358 boolits and slower powders. HS-6 has worked very well for me.

[garym1a2]

I use the 38 expander too, it helps a lot. I also only use 3.8grs of BE. Still I found this a great bullet to powder coat.

Pull a bullet and check your size again to make sure you aren't sizing the bullet back down with the case. I ran into this and had to change out the expander plug on my Lee 9mm die to a .38 s&w. Think the plug cost like three bucks to solve the problem.

Sent from my 0PJA2 using Tapatalk

[gwpercle]

Try backing out the taper crimp die, this will apply less crimp to the larger diameter boolit.
The crimp die has to be able to hold .355 J-bullets , mine is backed out about one full turn...trial and error will determine your exact amount of "back out" for your .357 boolits, I size mine .357 also ..
I also am using the Lee 120 TC boolit and this solved the swaging down.

Gary