Is .357 too big for a 9mm cast bullet?

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onceA6shooter
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Is .357 too big for a 9mm cast bullet?

Post by onceA6shooter » 24 Jun 2011, 18:57

My son gave me a Lone Wolf 40-9 barrell for Fathers day to shoot 9mm out of my G23 40 s&w. I also got some 9mm cast bullets that said they were .356 but when measured they were .357. I had discoverd the problem after loading some of the Bear Creek Supply 125 gr moly bullets. I tried one in my Dillon 9mm case gauge and it did not seat all the way. I sized 9mm case and it dropped flush in the gauge. I dropped the powder seated a bullet and it would not go flush in my case gauge. I took some of bell out thinking it might not gone back after seating and doing the taper crimp.

I measured the out side of the case of a completed round and it was .378 around the bullet. My manuals alll say that it should be .380 for the outer diameter so that was okay. Finally I measured the bullet itself and it was .357. I had some old Meister FMJs that measuerd out to .355, the normal diameter for a 9mm fmj. I loaded the Meister 124 grn fmj bullet and dropped it in the case cage and it went flush like the sized empty case.

The only difference between the two loaded rounds was the lead bullet was .357 instead of .355 of the fmj.

I dropped the lead rounds in the Lone Wolf barrel chamber with out any problem. I verified the fit was similar with Winchester factory round. I thought that there should be no problem since they seemed to chamber okay in the Lone Wolf barrell. Then I thought if it was oversized then I could have an over pressure problem, or kaboom if it could not pass through the barrel.

Pardon my ignorance of what limmts can be pushed.

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flyingirish04
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Re: Is .357 too big for a 9mm cast bullet?

Post by flyingirish04 » 24 Jun 2011, 18:58

I think so. I am pretty sure the answer is that it is too big. I would defer to some others on this board though.
Killed Two Stones with One Bird.

onceA6shooter
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Re: Is .357 too big for a 9mm cast bullet?

Post by onceA6shooter » 27 Jun 2011, 10:45

I always thouhgt that the COL was important for the round to fit in a magazine, but it seems that the bullet shape, ogive, plays a part in this too. My lead 9mm reloads would not fit in my Dillon case gauge or the factory glock barrel of my G17, but they did fit in the Lone Wolf 40-9 barrel. I decided to try shooting some after reviewing that all other dimmensions of the reload were in spec. They shot great through the LW 40-9 barrell in my G23, no malufunctions, with the only other change was a 9mm mag. No signs of high pressure on the brass.

Rechecking the COL of the reloads showed they were at 1.096 and it should have been 1.090. That is what Hornady shows for their 124 grn lead round nose bullets, while their 124 fmj is 1.150. I need to find the COL spec Bear Creek Supply bullets.

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