Case failures 40S&W and 10mm

[56hawk]

Trying to figure out what when wrong with my reloads. I had loaded up 50 rounds of 40S&W and 50 rounds of 10mm the night before.

The 40 was a load I have shot about 50 or so rounds with no problems. It's a 140 grain lead round nose loaded to 1.125 oal with 6 grains of 700X. Got the data from: http://data.hodgdon.com/cartridge_load.asp They don't list the exact bullet, but it should still be close to a starting load according to them. Chronographs out of my Beretta 96 at 1170fps. No signs of high pressure with any of my brass out of any of my guns.

My 10mm load was a 200 grain lead flat point loaded to 1.250 oal with 5.8 grains of 700X. This is the Lyman listed max and did 1090fps out of my S&W 1076. I had only shot six rounds of this load previously having worked it up from the starting load of 4.4 grains.

So I took this ammo to the range along with a bunch of other guns I was shooting. When I go to the 40, on my fourth round I felt a gust of hot gas in my face and noticed that the gun had jammed. If you look at the first picture below you can see that it took the back end of the case off right at the extractor groove. It knocked the transfer bar part way out of the frame, but did no actual damage to the gun. I disassembled it and checked everything when I got home.

Switching to the 10mm I had shot a few mags through it when on my 16th round had a similar experience as the 40. The case blew out right where the feed ramp is. Only thing it did to the gun was knock a spring loose from the decocker.

It was pretty obvious with the 10mm that I was just running to hot of a load. About half of the brass that I shot has a visible bulge where the feed ramp is. The 40 is the one I was going to ask about, but I think I figured it out while writing this. Looking at my notes, the oal seemed a little long. I had originally developed a load with this bullet for my HK USP. The ammo drops freely into the chamber of the USP, but not in the Beretta. I'm pretty sure that the Beretta fired out of battery.

My plan now is to work up a new load for both calibers. The 40 with the bullet seated deeper and with the 10mm I'm switching to Blue Dot to try to get more velocity at a lower pressure (I'll watch the brass a lot more carefully this time).

 

[rcmodel]

First thing I would do is buy a set of scale check-weights and see how far off your scales are.

Second thing I would do is change to a more forgiving, slower power then 700X in both 35,000 PSI cartridges.

Third thing I would do is use my tested accurate scales to see how close my powder measure is throwing charges.

Forth thing I would do is find some lead bullet data for the powder you are using.


Hodgdon does not list any lead bullet data for .40 S&W, and no Titegroup data for 10mm lead bullets as far as I can see.

Lyman #49 doesn't list Titegroup in .40 S&W with any bullet.

All that added together is what I like to call a Clue that Titegroup might not be a good powder choice for those two hi-pressure calibers.

rc

 

[gamestalker]

I would like to add a fifth thing to do, check your firearm for damage! I certainly wouldn't have continued shooting loads that are blowing out from obvious high pressures.

 

[56hawk]

Now, I'm back to being confused with the 40. I pulled the barrel out of the Beretta, and my reloads drop freely in and out. As you can see in the picture the case blew out when the barrel was open about an eighth of an inch. There is no way the hammer could drop when the slide is open this far, so I'm kind of at a loss as to what happened here. Anyone have any ideas?

rcmodel - I checked my powder scale and it's within a 1/10 of a grain. Also I have checked my powder measure and it also throws within a 1/10 of a grain.
I haven't seen any appreciable difference between lead and jacketed load data in pistol calibers. Regardless nobody seems to list data for a 140 grain bullet of any type.
By the way, why do you mention Titegroup? I don't think it's interchangeable with 700x.

gamestalker - The first thing I did when I got home was to completely disassemble both guns and check all parts. As far as I can tell there is no damage to any parts. Sorry if I was unclear, but I stopped shooting each caliber after it happened. Didn't expect to have problems with two different calibers on the same day.


Anyway, I'm planning on going to the range tomorrow and am wondering what loads I should try in the 40. I want to stick with 700x and I'm just going for target loads anyway. Hodgdon lists 6 grains as the starting load for a 135 grain bullet, so I don't know how much I should reduce from there. On the other hand does anyone think this might have just been a bad casing and have nothing to do with the bullet or powder?

 

[Walkalong]

700X is suitable for very light .40 or 10MM loads, but nothing more than that.

You do not blow out cases with acceptable charges of proper powders for the task.

You over charged a case, or cases.

Another thought, there were some issues with older federal .40 cases. I do not remember how they were marked vs the newer ones though.

 

[rcmodel]

anyone think this might have just been a bad casing

I thought you said in the OP you blew up both the .40 and the 10mm guns on the same range visit?

The cases that blew, blew at the unsupported section of the case right at the feed ramp.

That right there is enough information for me to conclude you are overloading both calibers, due to some so far undetermined or undisclosed problem in your powder weighing or powder charging procedures.

Hodgdon lists 6 grains as the starting load for a 135 grain bullet

One more time.

Hodgdon does not list any lead bullet data for the .40 S&W, and only lists a Nosler 135 grain JHP bullet using 700X.

They show NO loads for the 10mm using 700X.

rc

 

[56hawk]

I agree that the 10mm was right at the limit and it did bulge quite a few of the other cases right where the feed ramp is. This was with the listed max in the Lyman reloading manual. That is why I am switching to Blue Dot with it and starting over.

My question however is with the 40. I pulled a couple bullets and reweighed the powder, and they all came in at 5.9 to 6.0 grains. I loaded these rounds in a block and visually checked to make sure all cases had the same amount of powder. The round that blew out had no more recoil than any of the previous rounds. Also none of the other rounds I fired showed any signs of pressure. No bulges or flattened primers.

Another thought, there were some issues with older federal .40 cases. I do not remember how they were marked vs the newer ones though.

This is what I am starting to think happened. Sadly I did not recover the case head so I have no idea what the head stamp was.

The cases that blew, blew at the unsupported section of the case right at the feed ramp.

The 40 didn't. If you look at the picture the case was 1/8" out of battery when it blew and took the whole case head off. It even pealed the case into the extractor groove which would be impossible if the case was fully chambered.

One more time.

Hodgdon does not list any lead bullet data for the .40 S&W, and only lists a Nosler 135 grain JHP bullet using 700X.

One more time.

Do you notice a big difference between lead and jacketed bullets? Do you notice a big difference with 5 grains more bullet weight? Do you think a starting load for a 135 grain jacketed bullet would be extreme overpressure with a 140 grain lead bullet?

If so, what should my starting load be?

 

[rcmodel]

I think you should use something besides 700X you can find lead bullet data for.
But thats just me.

rc

 

[243winxb]

40 S&W Hodgdon >

This data is intended for use in firearms with barrels that fully support the cartridge in the chamber. Use of this data in firearms that do not fully support the cartridge may result in bulged cases, ruptured cases, case-head separation or other condition that may result in damage to the firearm and/or result in injury or death of the shooter and/or bystanders.

The old IMR 10mm data lists 700X 5.2grMaximum for a 200gr J bullet.

 

[56hawk]

The old IMR 10mm data lists 700X 5.2grMaximum for a 200gr J bullet.

Probably very good information. I'm surprised Lyman lists 5.8 grains. I've usually found their loads to be a bit on the conservative side.

 

[Walkalong]

I think you should use something besides 700X you can find lead bullet data for.
But thats just me.

I agree, and 6.0 Grs of 700X is a lot in the .40 with a 140 Gr bullet at 1.125 OAL, especially if the bullet gets pushed in a little when feeding. I haven't gone over 4.7 grs of 700X in the .40.

While 700X is fairly forgiving for a fast powder, it simply isn't the best choice here.

 

[56hawk]

I agree, and 6.0 Grs of 700X is a lot in the .40 with a 140 Gr bullet at 1.125 OAL, especially if the bullet gets pushed in a little when feeding. I haven't gone over 4.7 grs of 700X in the .40.

While 700X is fairly forgiving for a fast powder, it simply isn't the best choice here.

Was your 4.7 grain load with a 140 grain bullet? I want to reduce the load just to be on the safe side, but only have the Hodgdon data to go by.

 

[Walkalong]

Try 4.7 Grs 700X for a nice target load, or get a medium speed powder like N340, AA #5, Unique, True Blue, SR 4756, etc....

 

[243winxb]

Unsupported Chamber?? OP photo-Extractor cut in Barrel?

Looks like the Beretta 96 might have an extractor cut = unsupported chamber ??

 

[56hawk]

The extractor cut does not extend past the case head on the Beretta. Hopefully these pictures will make it more obvious that the case was not all the way in the chamber when it let go.

Walkalong - Thanks, I wasn't thinking about reducing the load by that much but I think I'll load a few between 4.5 and 5.5 and see if they cycle in all my 40s.

 

[Walkalong]

They always say, start low and work up. Cases like that are one reason why.

 

[ImjinScout]

From information that I have found before, the old Federal S&W.40 brass that was not to be used any more was just marked F.C., I did find a few in some old range brass that I had picked up. IIRC this brass was mfg. in the 90's and was having a lot of issues with blown cases.

 

[noylj]

Here are ALL the 140-145gn Lead bullet loads I have compiled. Always start at the lowest starting load.
For .40S&W, I wouldn't use a powder faster than AA5. Both AA5 and Silhouette seems to excellent powders for the .40, particularly for accuracy. Do not try to work up a max load for AA5 or ANY faster powder.
Bullet Weight Powder Weight Velocity Start/Max PowerFactor COL
Lee 401-145-SWC 145 231/HP38 5.0 1018 Start 148 1.125
Bull-X Lead 140 231/HP38 5.5 1070 150
Lee 401-145-SWC 145 231/HP38 5.6 1079 Max 156 1.125
Bull-X Lead 140 231/HP38 5.9 1120 157
Bull-X Lead 140 231/HP38 6.4 1190 167
L-FN 145 231/HP38 6.6 1259 Max 183
Lee 401-145-SWC 145 800X 6.7 1085 Start 157 1.125
Lee 401-145-SWC 145 800X 7.5 1185 Max 172 1.125
Lee 401-145-SWC 145 AA2 5.0 1070 Start 155 1.125
Bull-X Lead 140 AA2 5.6 1120 157
Lee 401-145-SWC 145 AA2 5.6 1154 Max 167 1.125
LC L-TC 140 AA2 5.9 1016 Start 142 1.115
Lead 145 AA2 5.9 1040 Start 151 1.115
Bull-X Lead 140 AA2 6.1 1140 160
Bull-X Lead 140 AA2 6.3 1170 164
Bull-X Lead 140 AA2 6.5 1200 168
Bull-XL-FN 140 AA2 6.5 1209 169
Lead 145 AA2 6.6 1155 Max 167
LC L-TC 140 AA2 6.6 1155 Max 162 1.115
L-RNF 145 AA5 6.8 1075 Start 156 1.060
Lee 401-145-SWC 145 AA5 7.2 1022 Start 148 1.125
LC L-TC 140 AA5 7.2 1038 Start 145 1.115
Lead 145 AA5 7.2 1072 Start 155 1.115
L-FP 140 AA5 7.5 1155 Max 162 1.135
Bull-XL-FN 140 AA5 8.0 1087 Accurate 152 1.135
Lee 401-145-SWC 145 AA5 8.0 1174 Max 170 1.125
Lead 145 AA5 8.0 1179 Max 171
LC L-TC 140 AA5 8.0 1179 Max 165 1.115
Bull-X Lead 140 AA5 8.2 1060 148
L-FN 145 AA5 8.4 1252 Max 182
Bull-X Lead 140 AA5 8.8 1150 161
Lead 145 AA5 80.0 1179 Max 171 1.115
Lead 145 AA7 9.0 1030 Start 149
LC L-TC 140 AA7 9.0 1030 Start 144 1.115
Lead 145 AA7 9.0 1065 Start 154 1.115
Bull-X Lead 140 AA7 9.2 1030 144
Bull-X Lead 140 AA7 9.8 1060 148
LC L-TC 140 AA7 10.0 1171 Max 164 1.115
Lead 145 AA7 10.0 1171 Max 170 1.115
Bull-X Lead 140 AA7 10.1 1110 155
L-FN 145 AA7 10.3 1231 Max 178
Lead 145 AA9 10.8 988 Start 143
Lead 145 AA9 10.8 1021 Start 148 1.115
Lead 145 AA9 12.0 1123 Max 163
Lead 145 AA9 12.0 1123 Max 163 1.115
Lee 401-145-SWC 145 Blue Dot 8.0 1091 Start 158 1.125
Lee 401-145-SWC 145 Blue Dot 9.0 1168 Max 169 1.125
L-FN 145 Blue Dot 10.1 1244 Max 180
Lee 401-145-SWC 145 Bullseye 5.4 982 Start 142 1.125
Lee 401-145-SWC 145 Bullseye 6.0 1066 Max 155 1.125
Lead 145 Clays 3.5 915 Start 133 1.135max
Lead 145 Clays 4.0 1034 Max 150 1.135max
L-FN 145 Herco 7.0 1236 Max 179
Lee 401-145-SWC 145 HS6 7.5 1055 Start 153 1.125
Lee 401-145-SWC 145 HS6 8.3 1166 Max 169 1.125
Bull-X Lead 140 HS6 8.9 1180 165
Bull-X Lead 140 HS6 9.3 1230 172
L-FN 145 HS6 9.4 1265 Max 183
Bull-X Lead 140 HS6 9.7 1260 176
Bull-X Lead 140 HS7 9.9 1190 167
L-FN 145 HS7 10.2 1233 Max 179
Bull-X Lead 140 HS7 10.3 1230 172
Bull-X Lead 140 HS7 10.7 1260 176
L-TC 140 N310 3.8 980 137 1.080
Lee 401-145-SWC 145 N330 5.3 1012 Start 147 1.125
Lee 401-145-SWC 145 N330 5.9 1140 Max 165 1.125
Lee 401-145-SWC 145 N340 5.5 998 Start 145 1.125
Lee 401-145-SWC 145 N340 6.2 1148 Max 166 1.125
Lee 401-145-SWC 145 Power Pistol 6.4 1058 Start 153 1.125
Lee 401-145-SWC 145 Power Pistol 7.2 1179 Max 171 1.125
Lee 401-145-SWC 145 Silhouette 6.6 1025 Start 149 1.125
Lee 401-145-SWC 145 Silhouette 7.3 1117 Max 162 1.125
LCL-TC 140 Silhouette 7.3 1132 Start 158 1.135
Cu-PFP 140 Silhouette 7.5 1255 Max 176 1.070
L-FP 140 Silhouette 7.5 1261 Max 177 1.080
L-FP 140 Silhouette 7.7 1286 Max 180 1.130
LCL-TC 140 Silhouette 8.1 1258 Max 176 1.135
L-TCBB 140 True Blue 7.7 1125 Start 158 1.130
L-TCBB 140 True Blue 8.5 1250 Max 175 1.130
Lee 401-145-SWC 145 Unique 5.0 1017 Start 147 1.125
Lee 401-145-SWC 145 Unique 5.6 1127 Max 163 1.125
Bull-X Lead 140 WSF 7.1 1130 158
L-FN 145 WSF 7.3 1237 Max 179
Bull-X Lead 140 WSF 7.8 1220 171
Bull-X Lead 140 WSF 8.2 1270 178
Bull-X Lead 140 WSL 5.2 1020 143
Bull-X Lead 140 WSL 5.7 1120 157
L-FN 145 WSL 5.9 1248 Max 181
Bull-X Lead 140 WSL 6.0 1180 165
Bull-X Lead 140 WST 5.5 1050 147
Bull-X Lead 140 WST 5.9 1110 155
Bull-X Lead 140 WST 6.2 1140 160
Bull-X Lead 140 WST 6.5 1180 165
Lee 401-145-SWC 145 Zip 5.0 995 Start 144 1.125
Lee 401-145-SWC 145 Zip 5.6 1126 Max 163 1.125
L-TCBB 140 Zip 5.8 1113 Start 156 1.120
L-TCBB 140 Zip 6.4 1237 Max 173 1.120

 

[Deavis]

Those cases look very similar to some I shot out of a Glock 20 years back, using fast powders in 10mm and 40S&W can be a bit troublesome. The loads I shot were WW231, all below maxes listed in loading manuals. Brass was shot out of a fluted MP5 chamber by the ATF before I got it, consistently lost case heads and extractors. Starline barss, not an issue, that brass, bad news, even in a fully supported Bar-Sto barrel.

Toss the brass and move to a nicer, slower powder like #7 or #9 for both.

 

[Striker Fired]

I shoot a lot of 40 cal. (2-96 Berettas,1-XDM)and I haven't really ever been impressed with any load with those faster powders .My favorite powder for it is N340 or AA#5.For lead I also like WSF and 3N37.The fastest powder that does like my Berettas is SR7625. This doesn't really sound like a overcharge case but I wouldn't rule it out.It's good to know the Beretta handled it well.
I don't consider the Beretta barrels as one of the "unsuported",but it isn't a complete support either.

 

[Walkalong]

When the fourty first came out, all the gun rag writers said the same thing, fast powders did not deliver the accuracy medium powders did. Not to mention pressure spikes.

 

[GLOOB]

Do you think a starting load for a 135 grain jacketed bullet would be extreme overpressure with a 140 grain lead bullet?

In this case, the answer may be yes. If the range between min and max load is very narrow (like it tends to be with small cases and fast powders), AND you're going up 5grains in bullet weight (3% heavier), then yes it might.

If so, what should my starting load be?

The rule of thumb I've always heard is to take 10% of the jacketed start weight and work up from there. You might want to even bump that up a few percent for the weight difference.'

You might also want to crosscheck with some other references or online data. I have loaded Unique in 40SW, but Alliant's data seemed pretty hot to me. When I checked around what other people were recommending, I found at least half a dozen other recommendations, and not one was even close to Alliant's max data. Most people weren't even within 20%. So I started with something like 25-30% less than Alliant's max load data using plated bullets. Shot and cycled fine.

When pressure is just slightly too high in a chamber with good support, the gun is trying to extract a case that's tightly wedged in the chamber. But the pressure isn't so high that it pushes out or blows the web. Like you noticed, the extractor is ripping off the case head. Those Berettas have a nice tight extractor, apparently. When my 40 loads get too hot, the first and only pressure sign I've gotten with my Glock (aside from borderline painful levels of recoil) are failures to extract. Cases still look perfectly fine.

 

[56hawk]

Took both guns to the range yesterday. Worked up a load with Blue Dot and a 200 grain bullet in the 10mm. Starting load of 8 grains did just over 1000fps. Maximum load of 9.6 did 1175 fps. No signs of pressure at all. The gun did jam a couple times with the hotter loads, so I think I will back it off a bit and make 9 grains my standard load with the velocity right at 1100fps.

With the 40 I did as walkalong suggested and reduced the load to 4.7 grains of 700x with the 140 grain bullet. Still does 1100 fps and cycles all my 40s except the Beretta that had the case failure. Looks like the extractor was damaged, since it fails to extract about half the rounds. Still think it was a random case failure and not the load, but for target ammo I'm perfectly happy with this reduced load.

 

[john wall]

This one is easy about Federal 40 and 10mm cases. As one who once loaded commercially, the older, weak case head Federal simply had FEDERAL and the caliber. The improved case design has two punch marks on the hull.

The inside of the old, weak case design resembles the old "Super Balloon" case design of yesteryear. (Google Super Balloon Cartridge Case Style) The improved case resembles a vacuum bottle near the case head.

I will not load the old style Fed hulls in 40 or 10mm. This requires sorting by head stamp, but is needed for max loads. Older Magtech (CBC headstamp) also has this style case.

BTW, 700-X is NOT a powder for full throttle loads. Near max loads work well in either caliber with HS-6. VV powders can get a little more speed, but redlining the Ten kills the brass. The large primer pocket makes the case head thin. Loading the Ten with lighter bullets at a higher speed will let the brass live a little longer.

 

[john wall]

This is an example of a Super Balloon case (in the middle) with 2 Solid Head cases on either side. The good thing about the SB is, it holds more powder. The bad thing is, it does not do well when loaded to high pressures.

The Super Balloon is still used in some low pressure cartridges. The reasoning behind putting this case design in high-pressure/heavy-bullet loads like the 40 and 10mm does not make sense. I have seen older 44 Mag hulls that were Super Balloon types.