40 S&W bullet sizing

[RonnieMilsurp]

I apologize if this is covered somewhere (I'm sure that's a common way to start a thread), but my search for 40 S&W pulled up zero results. Seems unlikely, but ok.

I cast some hard 200 gr bullets for the 40 S&W using the Arsenal 403-200-WFN mold, and they do indeed measure out to that diameter. Loaded up some rounds and they will not chamber. They are just lubed, not powder coated. Some factory rounds I had measure at .395 right about the case mouth, though admittedly they may have already started to taper.

I figured they need to be sized down, but when I pull up the Lee sizer punch for 40 S&W, it says it's .410". Am I missing something? Do I just ignore that and get a smaller sizer?

The cases are not too long, btw.

[Ed_Shot]

The common sizing die for 40 S&W boolits is .401". 41 caliber (as in 41 Mag.) is .410". What weapon are you loading for? With your 200 gr. boolit your cartridge overall length might also be a factor in your chambering issue.

[W.R.Buchanan]

And 200gr. is a bit much for .40S&W 200 gr is more for 10MM 180 is about the limit for .40S&W.

Randy

[cwlongshot]

The 40 & 10mm are .400 so generally .401/.402 for cast lead bullets is whats used.

The 41 Mag is .410 and often .411 & .412 bulelts are used when cast from lead alloys.


A .410 bullet, number one, probably wont even seat in the case let alone chamber in the gun.

CW

[MT Gianni]

I have a 40 Smith and Walther that needs 0.402" to group well and a Kahr that needs 0.401". The Kahr gets fed the Lee 145 gr to easily tell what's what.

[RonnieMilsurp]

The common sizing die for 40 S&W boolits is .401". 41 caliber (as in 41 Mag.) is .410". What weapon are you loading for? With your 200 gr. boolit your cartridge overall length might also be a factor in your chambering issue.

I bet the Lee site just didn't work right when it showed me .410 for the sizer. I do have the bullet seated deeply enough to get the COAL right.

After letting the slide slam home a couple of times on the loaded round, I see a ring on the ogive of the bullet about 5 thou above the case mouth, indicating (I believe) that it is headspacing/bottoming out on the bullet.

Since the bullets mic out at .403-4035, I will try the .401 and see if that gets me there.

Thanks, all.

[Dusty Bannister]

Since you are using the Lee APP bullet sizer, if the .401" die is a little too small for this handgun, it is easy to polish out to a slightly larger diameter if that is necessary. There is a sticky for doing that process if you have not encountered it in the past.

[fredj338]

AS noted, 401 or 402. IF you are measuring factory rounds at the case mouth at 395, that is seriously messed up ammo.

[DougGuy]

What gun? If you had the barrel throated, you could seat a .402" long enough to just barely cycle through the magazine, end of feeding/chambering issues.

I would be very hesitant using a 200gr boolit in the 40. With a 180 it runs out of headroom really quick, and can rapidly become an over pressure event *IF* you get even the slightest bit of setback.

When the 40 first came on the market I had a para dbl stack lower and I forget now who made the upper but I detonated a full magazine at the range loading a 180 at the max. Luckily all it did was blew the mag down and out of the mag well and spray brass fragments, powder, and boolits all over me and the floor.

The 40 is probably THE least forgiving autopistol caliber ever invented.

[RonnieMilsurp]

Since you are using the Lee APP bullet sizer, if the .401" die is a little too small for this handgun, it is easy to polish out to a slightly larger diameter if that is necessary. There is a sticky for doing that process if you have not encountered it in the past.

Thanks!

[RonnieMilsurp]

What gun? If you had the barrel throated, you could seat a .402" long enough to just barely cycle through the magazine, end of feeding/chambering issues.

I would be very hesitant using a 200gr boolit in the 40. With a 180 it runs out of headroom really quick, and can rapidly become an over pressure event *IF* you get even the slightest bit of setback.

When the 40 first came on the market I had a para dbl stack lower and I forget now who made the upper but I detonated a full magazine at the range loading a 180 at the max. Luckily all it did was blew the mag down and out of the mag well and spray brass fragments, powder, and boolits all over me and the floor.

The 40 is probably THE least forgiving autopistol caliber ever invented.

Thank you for the advice. It's an M&P (not 2.0). I am hunting out west and it's meant as a bear/cougar defense. I know ppl argue all day about what's the appropriate caliber for that. I am not pretending this is THE BEST and am sure that various side arms fit the bill. I just wanted something relatively compact that can be handled easily enough.

Do you suppose that keeping my loads more toward the minimum would keep me pretty safe?

[JonB_in_Glencoe]

SNIP>>>

Do you suppose that keeping my loads more toward the minimum would keep me pretty safe?
My 2¢
There is published data for the RCBS 200gr SWC in the Lyman CBHB#4. Try the starting load and work up. There isn't much case capacity and I noticed that the starting charges of all the different powders listed in Lyman are only 0.5 to 0.7 grains below Max.
good Luck.

[popper]

headspacing/bottoming out on the bullet. Yup, size 401 and try. Typically a TC bullet ogive starts about 20 thou above the mouth.
You might be getting 850-900 fps from your load. Not that bad but don't try hot rodding.

[W.R.Buchanan]

The 40 is probably THE least forgiving autopistol caliber ever invented. This is very true and is the main reason you don't Hot Rod this round!!!

Like the 9MM the 40 S&W runs at 35K psi. However unlike the 9MM the case is not as strong as the 9MM case so overloading is not a good idea.

If you need Hot Rod Loads for SD go buy some Factory ammo!

One last thing that has been mentioned here many times,,, DO NOT RELOAD FEDERAL CASES MARKED "FC" OR "FC10" !!! These early cases had Very Weak Case Webs that didn't extend up far enough to cover the Feed Ramp in the Chamber. They were prone to failing at that place causing the Majority of Glock Kabooms ! See Pics

This was corrected in later brass and the problem has been pretty much eliminated. But the cases are still out there just waiting to blow up in unsuspecting hands.

Randy

[RonnieMilsurp]

Thanks, everyone! As for brass, I'm using new Starline.

[popper]

Yup, found one of the FC brass. surprize. No damage done, just a what the heck moment.

[justindad]

I’ve loaded the RCBS 10mm-200-SWC for .40S&W. There was very little case volume. The RCBS boolit is 0.717” long. If your Arsenal boolit is longer than that or you otherwise reduce case capacity, be careful using the Lyman Cast Handbook load data.

[cwlongshot]

I experimented with a G24 & 222 & heavy 200g Lyman hard cast.

https://youtu.be/qYP16iAeWS8?si=0mGjIVtA-bTRR40C

https://youtu.be/HZ6gNfW6yt8?si=mvF0kV-oyd2ClYp1

[RonnieMilsurp]

Thank you! The Arsenal bullet is actually only .60".

[Cast10]

Slug the barrel. That will give you the best idea of sizer.
My Glock 20 uses the Lee .401 sizer. I shoot 180’s. All you need for what you’ve stated. In bear country, a good hard cast boolit. Maybe water drop. I also PC my boolits. Life is much easier knowing there will be no leading at velocity.
Also, my Glock ‘kerplunked’ the loaded cartridge just fine. However, I have a carbine that’s tight chambered and exhibited the same marking as yours. To correct that I used a M die which has a longer shank on the belling rod which stretches the case further down and keeps you from swaging the boolit when you crimp, as well as eliminating case bulge from the oversized lead boolit. I shoot an alloy that yields 11.3 and seems plenty hard. I’ve killed hogs out to 120yards with no problem. I love Starline brass. I use the Lee 401-175-TC mold. Best of luck to ya.

[DougGuy]

If you are dead set on taking that 40 into the bear woods, don't hesitate to have that barrel throated so it doesn't confine you to shorter COA and or boolit diameter small enough that it will feed reliably. Load up a dummy with your 200gr and see what the maximum length your magazine will cycle with. Now pull the barrel and use it for a plunk gauge, see how much of that same dummy case sticks out from the barrel hood.

*IF* the barrel was throated to the point where the longest dummy that you can cycle through the magazine will now plunk and turn, now you can start figuring out load data. This way you have effectively exposed the maximum amount of case volume so you probably have some wiggle room with powder charges.

[justindad]

After letting the slide slam home a couple of times on the loaded round, I see a ring on the ogive of the bullet about 5 thou above the case mouth, indicating (I believe) that it is headspacing/bottoming out on the bullet.

Since the bullets mic out at .403-4035, I will try the .401 and see if that gets me there.

Thanks, all.

5 thou is pretty small, so you could be head spacing on the boolit. On the other hand, you may have the boolit hitting the barrel throat. If the lead is wide and your throat shallow, then sizing down your boolit will do nothing. Can you measure the ogive diameter at the indentation?
*
Consider making a few dummy rounds without crimping after you seat the boolit (requires a very light case mouth bell, if any at all). Attempt to chamber the boolit, if it fails to chamber then seat deeper by 10 thou and repeat. The WFN makes your boolit shorter than the RCBS version used in the manual, so you have some room to shorten your OACL. Just be aware that there are aspects of bullet design that can increase pressure for as of yet unknown reasons.
*
Your brass may have sized your boolit for you, so pull one and see if the size is still .403”.

[DougGuy]

With an unthroated barrel it's a safe bet that it will not ever plunk with a .403" with ANY of the sides of the boolit ahead of the case mouth. Like where the ogive of the boolit is marked .005" in front of the case mouth, I suspect that the boolit was seated out farther, and was hammered back into the case by the OP's numerous attempts trying to get it to go into battery.

Meaning that if he would have ejected the round the first time it wouldn't plunk, the "witness" mark would be a good bit farther up from the case mouth than .005"

The 40 is MUCH harder to load for successfully with heavier (and longer) boolits that need to be seated far enough in the case that it will feed and plunk. And this compounds the pressure issue. It NEEDS the throat relieved so that a longer COA can be used.

[44Blam]

With 40 S&W, I've had great success with the NOE HTC-402-188-WFN and AA #7 powder. The HP and CUP points tend to chamber a bit easier than the flat points...