Best solution for .40 S&W

[donloftus]

I have a problem with my Sub 2000 in .40 and I believe I'm getting gas cutting due to undersized bullets, although the roughness of the barrel might be a contributing factor. I bought this up on the Kel Tec forum and one person suggested I also bring it up on this forum since the problem is more than just with the barrel. I have some photos of the problem here: http://www.pbase.com/dloftus/40_chamber

I have about 1000 rounds of this stuff that I got from a friend (who got it from the guy who reloaded it) and was just going to "shoot it up to use it up" and then reload with proper bullets. Accuracy is bad and some of the bullets, once the leading builds up, go sideways through the target at about 20 yards. My thought was to pull all the bullets (vice grips and my Rock Chucker press) , save the powder and check the charge and recast the bullets to a proper size then reload the cases (on a Dillon 650). Does that sound feasible or should I just plink with it until it's all gone, at which time I would reload with proper bullets? I would have to get a mold, since I don't cast for .40 yet, any suggestions on a mold that would drop slightly oversize bullets with wheel weights? I'm just trying to get an idea of the best way to handle this. Thanks for any suggestions.

Don Loftus

[9.3X62AL]

I concur that you are very likely getting gas blow-by via undersized bullets, which is setting up a leading scenario within your barrel. I like your idea of casting .402"-.403" bullets, and sizing them to that spec.

Be aware that most 40 S&W die sets "assume" the use of .400" jacketed bullets. This means the the expander plug will likely be .395"-.396" diameter, and trying to seat a .402"-.403" cast bullet into a case mouth that small will almost certainly reduce bullet diameter. An expander spud dia./bullet dia. differential of about +.002" to +.0025" for the bullet is ideal.

The bullet sleeve within the seater die may not accomdate a bullet much wider than .402". If you need more clearance, you or a machinist will need to relieve that sleeve outward a taste.

Lyman/RCBS H&I sizer dies are common in .400" and .401", but seldom any larger; there are 3-4 suppliers here that can make Star, Lyman/RCBS, or Lee sizers at fair prices.

Lastly, DO NOT go Mongo Strong with taper-crimping. Cast bullets WILL BE REDUCED IN DIAMETER via over-application of taper-crimping force. Unlike jacketed bullets, cast bullets don't spring back under such force, leaving you with an undersized bullet likely to "telescope" on feedramp contact, which boosts pressures greatly, which can wreck pistols and their operators. Even if it doesn't telescope and set up a kB, it's undersize--and will lead the barrel. So you've wasted all the effort expended to get the diameter correct.

The 9mm Luger, 40 S&W, and 10mm are not very lead-friendly pistol calibers. They all run at relatively high pressures, many of their barrels feature ridiculously fast twist rates for the short bullets they are handling, and these factors in concert are hostile to lead bullets. These calibers are more like rifles than handguns, in many respects, so I treat them like rifles--STRICT adherence to bullet/barrel or throat diametric integrity, fairly hard bullet alloys, and fairly soft lubes. These strictures have given me good success with these problematic pistol calibers. E.g., my 9mm bullets are NEVER under .357", are usually in 92/6/2 alloy, and are lubed in a Lyman 450/4500 with 50/50 Alox/beeswax or Lars' Carnauba Red.

[chrisw]

have you slugged your barrel yet?

welcome to the sight!

[Any Cal.]

I have used waterdropped range scrap sized to .401 with no issue in full power 10mm. I have also had plenty of leading from bullets that looked just like those... If they are leading badly, you will have to do something different, so you might as well pull them. Easiest way to get an oversized mold is order one from accurate or mountain molds, or whatever noe has in stock right now. You can also let lead splash up between the mold halves for an impromptu beagle...:-)

Like was said though, if the barrel is oversize, none of it will matter.

[runfiverun]

he measured everything.
and Allen pretty much said everything i would too.
the only other thing that could be done after the right diameter boolits are obtained,is to cut that little step in the throat.

whether you shoot them or knock them apart is up to you.
if it were me i'd pull them down, toss the powder and remelt the 2/6/92 alloy into something else.

[donloftus]

have you slugged your barrel yet?

welcome to the sight!

Yes, the size is .401 to .4015. I show that in the photos, but you may not be able to load them. Let me know if you are having any problems. I really appreciate the information, especially about the problems with lead bullets in the 9mm and .40 S&W. I do load 9mm and have had problems with lead bullets to the point of not using them, so I will have to reevaluate my set up. One thing I also noticed with 9mm was that I got a ring of lead as the bullet was being seated and removing the mouth flair. That little bit of bullet movement as the mouth closed raised a ring that would get pushed into the barrel which also helped with leading. I believe it would be best to perform the bullet seating and crimping in two separate operations. Thanks for the help.

[mpmarty]

Hang in there and figure it out. I shoot 10mm cast and "make major" for IPSC with two different pistols and have no leading even though I lube with 45/45/10 or 50/50 JPW/LLA.

[runfiverun]

it's always best to seat and crimp in two separate steps.
and by crimp i mean iron the case flat just enough to hold the bullet in place
without damaging it.

[Any Cal.]

If you crimp less you won't get the shaved ring of lead. I don't seat and crimp seperately or use fancy sizers, just load and shoot. I do believe my barrel is .400 though, so .401 is .001 over. That blue lube and hard bullets caused leading for me, so I wouldn't worry too much about how your gun works with those particular bullets, softer lube and larger,softer boolits will be a whole different story.

[9.3X62AL]

Darn it, I knew I left something out--seat and taper-crimp in two die steps. I'm glad you guys were back-stopping me on this play!

[Wolfer]

I think your on track to fix your issues and I'd probably fire lap that barrel also.

[MT Gianni]

My Lee 175 casts around .402. Even if you needed to beagle one that would be a place to start when you are ready to cast.

[donloftus]

My Lee 175 casts around .402. Even if you needed to beagle one that would be a place to start when you are ready to cast.

I'm showing my ignorance here, but what do you mean "beagle one"?

[alfloyd]

Go to this link for more info.
http://www.castpics.net/subsite2/MoldMods/BDE.pdf

Lafaun

[popper]

optical illusion or the roughest bbl I've seen. That sharp step into the lands doesn't help either. The Lee 401170 TC or SWC work fine in my 40s.

[williamwaco]

it's always best to seat and crimp in two separate steps.
and by crimp i mean iron the case flat just enough to hold the bullet in place
without damaging it.

My rule for crimping these is:

If you can see the crimp it is too much.
If you can see the flare, it is not enough.

See:

For more ideas.

[kweidner]

OMG what a rough bbl. Fire lap that sucker. looks like it was cut with a dull rock. Seen a few cones like that but never a bbl. Gonna take some time but it should help.

[donloftus]

OMG what a rough bbl. Fire lap that sucker. looks like it was cut with a dull rock. Seen a few cones like that but never a bbl. Gonna take some time but it should help.

Yes it is a rough barrel and I thought it was the real problem, but when I slugged the barrel I came to the conclusion that undersized bullets were the biggest factor. But the rough barrel is not helping. I fired about 100 rounds of jacketed to see if it would help, but it seemed to have little effect. I do have some various grits left over from when I ground my own telescope mirror, so I will eventually try the fire lapping. It sure couldn't hurt and now I know how to beagle a mold, thanks to alfloyd, if I open the bore too much. Thank you everybody for the input.

[9.3X62AL]

My Lee 175 casts around .402. Even if you needed to beagle one that would be a place to start when you are ready to cast.

I'm another fan of this mould design. It has shot well in all of my 40 S&Ws (4 to date). I imagine my copy of the Lee mould casts a few clicks large, since it "cleans up" completely in a .401" H&I die. It shoots nicely in the 10mm, too.

[Catshooter]

My Kel-Tec Sub-9s barrel was one of the roughest I'd ever see too. I fire lapped it and boy oh boy did it help with both leading and accuracy.


Cat

[donloftus]

My Kel-Tec Sub-9s barrel was one of the roughest I'd ever see too. I fire lapped it and boy oh boy did it help with both leading and accuracy.

Cat, what procedure did you use for fire lapping? Did your barrel look as rough as mine? Thanks for any info you can pass along.
Don

[Catshooter]

Don,

Mine looked every bit as good as yours. Maybe even worse!

I used the Lead Bullet Technology set up. He will sell you a small bottle of lapping compound. I just followed his instructions. If I recall, I shot about 55 rounds. I think it was a Lee 115 grain tumble lube boolit over one grain of Red Dot. It wasn't enough powder, ten or fifteen rounds stayed in the barrel and I had to drive them out.

The weapon would group about four inches at 25 yards prior. After I was done it would put a full mag (33 rounds) into an inch at the same distance. Maybe an inch and a quarter. It was easy.

I've fire-lapped about 20 firearms over the years. Enough to use up a bottle and a half of the grit. It usually helps, and usually helps a lot.

The reason there is soot on the outside of your brass is the Kel-Tec is a blow back action. They all do that.

This help?

Welcome to the site Don.


Cat

[donloftus]

Cat,

Yes, you have been very helpful. It gives me encouragement that my Kel Tec Sub 2000 will eventually work well with cast bullets. I'll do a search on Lead Bullet Technology and research fire lapping more closely. I have heard it can be done with powdered grit by coating the outside of your bullets and firing about 20 rounds each with 200, 400 and 800 grit. Thanks again for the info.

Don

[runfiverun]

don't find it there david tubb may have what you want.
800 grit is about as far as i'd go.