.358 Trouble in 9MM

[swmass]

Checking back in. I have already tried to seat the bullets as short as 1.010 and still have the problem. There's a picture posted above and that is where my bullets are getting marks from hitting inside the barrel. I have the TC mold and it drops way small. That's when I got the idea to try a 358 mold. I've got top punch, 6 cavity mold and a pair of handles tied up in the bullet design. My glock loves em at 357 and I do too which is why I want to use this bullet in the m&p as well. I know it feeds them fine already. I also know the restraints of that bullet caused by its shape. For around the price of a new mold I'd rather just have the barrel done. It's gonna see many thousands of rounds so I'm just gonna do it now and be done with it. I'll check back in once I get it back. I'm sending it out Monday morning. Thanks for all the help guys

[Shiloh]

I had the same trouble with that boolit in my M&P 9. The throat would not take anything larger than .355. I sent the barrel to DougGuy and had the throat opened up (and crowned) It shoots the lee 358-125 like a dream.

Love that boolit.

It sits deeper in the case than 9mm boolits, so I worked up a load with Unique.

Shiloh

[LAH]

Lloyd my CZ 75 eats it all but for some reason my two MPs just won't work with 358s.

[DougGuy]

Here is a Glock G19 polygonal barrel I did for the same reason. Customer wanted to use .358" and this has some .3585" freebore and then it starts a long taper. These will plunk the long flat nosed boolits as long as you want to seat them, until they won't cycle through the magazine. It would dang near plunk them if you seated the boolit upside down. The longer throats shoot lights out.



20° crown done in the lathe



Feedramp gets a tiny radius and melted in everywhere



The 9mm of all pistol cartridges is likely the single most dangerous cartridge if boolit setback occurs. Pressures can skyrocket unpredictably. That last .015" you needed to slam the end of the slide home can set a boolit back in the case enough to send pressures well in excess of 60,000psi. Throat the barrel, remove the interference, and use the load data as it is published with the published COA instead of seating deeper and creating potentially a secondary problem, as a workaround to the first.

A further note on Glock, S&W M&P, all poly framed Springfields, Walther, and any other tenifer or melonite or salt bath treated barrel..

These are tenifer hardened barrels and man, let me tell you they are HARD! Need coated carbide to cut these, I have a custom made reamer to my own specs that set me back several hundred bucks and it is the ONLY thing that will touch these salt bath hardened barrels. The Glock is not just surface hardened, it's all the way through. Have a carbide 20° crown cutter and all it did was SHINE the end of this barrel. I had to crown it in the lathe. Witness the carbide throater's work in the photo above, it cuts smoothly enough that no follow up polishing is needed, and with the hardness of these salt bath barrels, there isn't much beside diamond abrasives that would even polish them anyway. It is almost better to invest in the KKM or Lone Wolf stainless barrel, much easier to make it cast boolit friendly.

[rsrocket1]

I use both the Lee TL356-124-2R and 356-120-TC in my M&P 9FS (actually an MP& 40 with the factory stock 9mm barrel) and a Shield 9. My barrels slugged at 0.3545" with a 0.356" throat. The bullets drop at 0.358" and after I powder coat them, they are 0.360". I can shoot them as is, but I have to seat both bullets to a 0.27" seating depth. That puts the top tumble lube rib and the conical part of the TC bullet at the rim of the case. This prevents any part of the 0.360" diameter of the bullet above the rim. It also limits the maximum velocity I can attain because with such a small volume inside the case, I have to reduce the charge to prevent going over pressure.

The ideal velocity for my guns is about 1100 fps so I need to seat shallower. I can do this by sizing the coated bullets to 0.356". With that, I can seat either bullet quite a ways out without hitting the lands and get enough powder in the cases to stay under SAAMI max pressure and get the desired velocity.

Oddly enough, I can shoot these in my Beretta 92FS which has a 0.357" groove diameter and still not get any leading whatsoever. The bullets are relatively soft (straight reclaimed trap and skeet shot) but I think it's the powder coating that prevents any gas cutting of the lead since none of the lead is exposed.

[Lloyd Smale]

well this made me go to the range. I had just loaded some 9s with the 120 rf lee because I wanted to try coated bullets. I had all kinds of failure to go into battery. I went home and grabbed a can of the last batch I loaded with the same bullet and they ran like a top. I figured it must be the coating. I was wrong. I went home and found the new batch had the bullet seated out just a smidge farther. For grins I set the die to the old batch and pushed the bullets down a bit more in the case and they ran like a top. this bullet must need to be seated a bit deaper then most.

[OS OK]

Perhaps, but this is as close to an all around bullet I have…mdi...

I have to agree, it's just I have a different approach for the ogive in the autoloaders…I PC them and size to bore size…no more oversize boolits. I think that's why I haven't had any problems going into battery.
If you oversize and lube you may not get a foolproof OAL without getting shorter…High pressure? Just rework your loads a bit?

OS OK

[6622729]

Perhaps, but this is as close to an all around bullet I have. I use it in 3, 9mms (Ruger LCPs, FMX, and a Tokerev), two .38 Specials and a .357 Magnum. Just because the bullet has a crimp groove does not mean you have to roll crimp into it. Perhaps the ogive is "wrong" (why?) for a semi-auto, but I have seated this bullet to an OAL of 1.125" and it chambers nicely in my 9mms...

If you are powder coating AND getting leading, I'd step back and look at what you are doing. I'd be looking at how hot a load you're trying to run and maybe how soft an alloy you are trying to use. You're awfully short with those rounds too. Since these are for more than 1 gun, I'd probably defer to the case gauge as you're standard and anything that fits the case gauge but doesn't chamber, then I'd be looking at the gun.

[A pause for the COZ]

I have a few 9's and I can tell you when it comes to cast bullets. They all like different things.
Some will feed any type of bullet I try, some are fussy and will only feed a certain profile.
Some will chamber one type and oal and not others.

I have a Star model B that feeds fine but has a tight chamber. My favorite big fatty 147gr pills are a no go.
120 gr Truncated cones feed, chamber, and shoot fine. So thats what it gets. Keep looking you will find one it likes.