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Arrow
05-26-2014, 11:04 PM
I am shooting a glock 20 with kkm barrel. I have a mihec 200 10mm mould. Shooting longshot powder. They are sized .402 and my barrel slugs .4005-.4001. I have tried Lyman moly lube as well as carnauba red. I tested loads from 8.2-9.0 in .2 grain increments. Bullets casted from straight wheel weights. I feel like I have tried everything and still keep getting leading. I am new to casting And I'm getting leading in everything 9mm, 10mm, .44 mag. I'm not too worried about the other two calibers right now, the 10mm is my main concern. What am I doing wrong? Thanks

bruce381
05-26-2014, 11:39 PM
over crimping? OAL to long? jamming into barrel leade?
try differnent powder I have had leading before that was seemingly cured with a powder change.
Thats all I got

Sgtonory
05-26-2014, 11:52 PM
Are your boolits being swaged down? Pull a loaded one. What crimp die?

sigep1764
05-26-2014, 11:54 PM
One my barrels was a little rough when it was new. I shot a few hundred jwordsthrough it and it smoothed up enough and didn't have any more leading. Maybe try a softer lube as well. I am pretty new to this but have had really good luck so far in every 9mm that I have. I now have one load to work in all four of my 9's. Lee 356-120 tc sized 358 lubed with Lyman Alox NRA over 3.7gr of PB at oal of 1.033. YMMV.

freebullet
05-27-2014, 12:38 AM
Pull a boolit and measure it. Over crimping can resize your boolits, that leads to leading.

When using ww and other high antimony leads you can get antimony wash in the barrel. Try describing your leading or better yet post a good pic. That will help folks help you.

singleshot
05-27-2014, 12:39 AM
According to my load data, you're WAY OVER MAX charge and in an over-pressure situation. My data shows a starting load of 7.0 and max of 8.2 grains of Longshot with a COL of 1.26. Start by reducing charge to 7.0 gr and see how that shoots.

Bzcraig
05-27-2014, 01:08 AM
According to my load data, you're WAY OVER MAX charge and in an over-pressure situation. My data shows a starting load of 7.0 and max of 8.2 grains of Longshot with a COL of 1.26. Start by reducing charge to 7.0 gr and see how that shoots.

Though I didn't look up his load data, I was leaning toward using j-word data instead of reducing for cast.

Whitespider
05-27-2014, 07:38 AM
A detailed description of the "leading" (or a picture) would tell us a ton more. There's different types of leading... each normally caused by it's own unique problem. Is the leading on the lands, in the grooves, at the breech, muzzle, full length?? Does it come out of the barrel in long thin wiry strips, or as chips, or both??

Without that info I can only go with what's in your OP...
The most obvious appears to be you're running pressures way too high for the alloy. Hodgdon lists 8.2 grains of Longshot as maximum (35,000 PSI) with a 200 grain jacketed... depending on several variables, your pressures could be well above that with cast lead. I ain't sayin' WW metal can't be used at 35k PSI, but everything needs to be perfect... including the alignment of certain planets (at least lube, diameter, barrel condition, pressure curve, seating depth, and loading technique).

First I'd pull a couple boolits from the reloaded cartridges and verify the bases ain't being sized-down during seating. Then I'd back that load off to maybe 6.5 grains and work up from there. You may just find that everything runs clean 'n' mean at something 'round 7.0-7.5 grains.

44man
05-27-2014, 08:25 AM
I never believed it much but powder can have an affect. Trying to find a sub for 4759 in my 45-70 BFR I tried 5744 and got a barrel full of leading. I get zero with 4759.
Softer lubes are always better too. Been shooting my Marlin 30-30 using Felix or one of 357 maximums great lubes at over 1900 fps and have finally gotten to under 1" at 100 yards and zero leading. Ben's Red works in it too.
I don't shoot toy :-P guns so I don't know much about them but things should still work.

gray wolf
05-27-2014, 12:58 PM
A detailed description of the "leading" (or a picture) would tell us a ton more. There's different types of leading... each normally caused by it's own unique problem. Is the leading on the lands, in the grooves, at the breech, muzzle, full length?? Does it come out of the barrel in long thin wiry strips, or as chips, or both??

Thank you WHITESPIDER Is it possible you could go over the different type of leading conditions that you mention in your post ? Perhaps give a little list of each one and what causes it and the possible cure.

Silverboolit
05-27-2014, 01:27 PM
Do you have the Lyman 4th edition? They are listing many powders for the 10mm, and not any of them even approaches what you are trying to do. Are you loading for max performance? If you are, a gas check design may work better. If you are having leading in all of the cals. that you are loading, check the load references.

If it were me, I would ditch the longshot and use either red dot, power pistol, unique, or the others listed in the manuals.

Whitespider
05-27-2014, 02:45 PM
Thank you WHITESPIDER Is it possible you could go over the different type of leading conditions...

Read this...
http://www.lasc.us/Fryxell_Book_Chapter_7_Leading.htm

Arrow
05-27-2014, 03:21 PM
I am loading for max performance. I have read the thread about others pushing this bullet hard. I haven't pulled a bullet and miced it yet but I will. I don't usually go off load data for 10mm because it is usually way too light. I have shot some underwood ammo and measured case expansion and an using that as a guideline for pressure testing with these loads. 9.2 grains I starting to show pressure. How are others pushing this bullet hard without leading? Thanks for the help

gray wolf
05-27-2014, 05:35 PM
I am loading for max performance.
What kind of performance would that be ? The 10 Mill does quite good as is, even with less than max book loads.

petroid
05-27-2014, 05:42 PM
+1 on pulling and measuring a boolit. Overcrimping can swage a boolit down as well as just the act of seating if the case isn't expanded enough. Which dies are you using? I would suggest measuring the inside of an expanded case. If it is more than two or three thou smaller than the boolit, it is likely swaging it down upon seating. Are you water quenching? It really helped with my 40sw

Silverboolit
05-27-2014, 05:43 PM
Underwood lists a 220 gr. lead flat point at 1200 fps. Is this what you are after??

Arrow
05-27-2014, 07:18 PM
I will check a pulled bullet for diameter. I am using hornady dies. My chrono got shot (not by me. Lol) so don't know velocity. But a 220 at 1200 mean a 200 should be able to go at least 1300. There was a guy on the other thread (sorry don't remember your name, ctour or something like that) was pushing this bullet to almost 1400 fps out of a 6" barrel. He got a little leading so he slowed it doe just a little bit and everything was good. He was using a softer alloy though.

Silverboolit
05-27-2014, 08:38 PM
Good luck on your quest.

Whitespider
05-27-2014, 09:42 PM
Maximum performance is a measure of more than just raw horsepower.
You can build 10,000 HP into a car, but it means nothing if the tires disintegrate on launch... that would be considered poor performance.
If you're pushing a boolit to the point it leads the barrel, which near always automatically degrades accuracy, you're moving away from maximum performance, not closer to it... actually, it's damn poor performance.

leeggen
05-27-2014, 10:25 PM
If you will seach under char Gar's name and 40 cal you will find alot of imfor. that will help you greatly. He has many threads on that cal. I know you said 10 mm, but his threads will still direct you accordingly. His treads help me with my 40 and I got started off on the right foot. For accurate help you need to tell where the leading is and all the imfor. you can. your answer might just be coww + tin and antimony and water drop it, or as complicated as barrel cleaning and lube, or metal barrel is made of ( steel or stainless ) twist rate and length.
Good luck and please get appropreate load data.
CD

Silverboolit
05-27-2014, 10:40 PM
A good friend of mine once said " You can get all the power you want out of an engine, until it fits loosely into a 5 gal bucket."

I hope that your Glock doesn't.

Virginia John
05-29-2014, 09:00 AM
Whitespider has a point, that is to look at where the barrel is leading which might lead to the cause.