Why is it

[parrott1969]

I just loaded some commerical cast 40 cal bullets and had great sucess with it. So why is it that sucess with the 9mm eludes me? Murphy has given me several tips that I have yet to try, but it seems to me that if I followed the same procedure for 9mm as the 40 then it should work. But it doesnt! Really has me fuzz buzzeled! I think the problem with 9mm is the twist rate. Any other ideas out there. Oh, by the way, I have tried everything with the 9mm sized .357, .358, 124 grain commerical cast, 125 grain water dropped ww with tumble lube, same pan lubed, and 147 grain commerical cast, different powder, everything. I have com close using dardas 125 grain bullet with blue dot but still had smearing but it was better than the stripping that I got from the other powders. Any ideas?

[mpmarty]

Slug your bore!
I once had an Astra 600 in 9mm and the bore slugged out at .362" It wouldn't shoot anything very well.

[Calamity Jake]

124 grain commerical cast, 125 grain water dropped ww with tumble lube, same pan lubed, and 147 grain commerical cast. Any ideas?

As stated above, slug the barrel then size .001-.003 over
All the boolits you have tried may be to hard. Try your 125 in WW air cooled and your pan lube.

I have a Smith 59 and a Firestar 9 both shoot AC'ed boolits just fine.

[mdi]

[QUOTE=Calamity Jake;885873]As stated above, slug the barrel then size .001-.003 over
All the boolits you have tried may be to hard. Try your 125 in WW air cooled and your pan lube.

"If ya don't slug, get ready to scrub". It is necessary to know what the bbl. dia is to run the proper sized boolit through it. I haven't found it necessary to water drop any of my boolits and shoot a variety of ammo from 125 gr 38 Spec up to 230 gr 45 ACP. If they fit they usually don't lead the bore.

[parrott1969]

Thanks guys, I slugged it a long time ago measured .355 my boolits are .358. I will try letting them air cool. Hard to belive that a boolit being too hard can cause problems, especially when its oversized.

[leftiye]

Try sizing them a little smaller maybe. I've got a 22 Hornet that has a .228 freebore, and I've been getting leading at the leade area, I'm thinking sizing too much when fired. Mine is with heat treated boolits, and the too hard might add to the problem in this case (harder to size down), maybe gas cutting around the boolit. Just some guesses to consider. Ironically, my 9mms don't give me any problems. Maybe you've got a rough leade?

[Nate1778]

I had the same issue with mine, I was at my wits end. Jumped to Unique (from HP38 and Red Dot) and a TC TL bullet and leading went away. I am loading on the mid to light range as any higher and it starts back. My non-informed conclusion is the 9mm is a high pressure cartridge, and I found it does not take much to push it past the bullets capability.

[nicholst55]

Almost all 9mm bores are rifled 1:10". Some have suggested that a slower twist, say 1:16", would be better for cast boolits. A few are rifled that way currently, and some aftermarket 9mm barrels sport a 1:16" twist.

I don't shoot enough 9mm normally to worry about it, but it might be something to consider.

[cbrick]

Hard to belive that a boolit being too hard can cause problems, especially when its oversized

Not at all hard to believe, too hard is probably the single biggest cause of leading. The term "hardcast" made popular by commercial casters has caused a great deal of grief and leading among new boolit casters. Harder is not better . . . it is simply harder and can and does cause it's own problems.

You could also in addition to air cooled WW try the slowest powder that will give you the velocity your looking for. Proper boolit fit, an alloy that's not too hard and a slower powder can help cure a lot of problems.

Key word here is "proper boolit fit". Proper fit can cure many ills including helping with too hard of an alloy.

Rick

[Edubya]

Almost all 9mm bores are rifled 1:10". Some have suggested that a slower twist, say 1:16", would be better for cast boolits. A few are rifled that way currently, and some aftermarket 9mm barrels sport a 1:16" twist.

I don't shoot enough 9mm normally to worry about it, but it might be something to consider.

I have two XD-9s and one is the factory fitted barrel, target grade and the other is standard. The target grade has a tighter groove dimension (0.3545 -vs- 0.355) and it leads less with my 0.357, 12 BHN boolits. I have never checked the twist rate, I'll have to do that. I had just accepted that the diameter made the difference.

EW