357sig @1700fps, I think I've run out of barrel

[Jayne]

Just for fun, I loaded up some 357sig using 90gr Sierras over 9.0gr CFE Pistol, and out of my converted G23 (4" barrel) I got an average of 1669 fps. The max load in the book is 9.5gr, so I was sure if I bumped it up a little bit I could hit 1700 fps.

Today I got to the range and fired the remainder of the 9.0gr rounds just to check the consistency of today vs. last time. Today's reading with those same rounds averaged 1664 fps, so close enough to the prior number of 1669.

The 9.3gr rounds were noticeably louder, and were producing average velocities of... 1670 fps.

No pressure signs at all, they looked identical to the factory ammo I fired (125gr speer, so not relatable in terms of velocity vs. my handloads).

I'm guessing I'm out of barrel length, all that extra is just making a larger blast outside.

CFE Pistol shows the highest velocity and not maxed out pressure of all the loads I've seen, so I would try other powders but they're all starting at a disadvantage compared to the CFE.

Lighter bullets maybe?

 

[Slacker]

I ran into the same issue with 90 gr 9mm major steel challenge loads.
Try a slower powder like WAC or VV.

 

[Jayne]

Update to this. The poly80 357sig I assembled has a threaded barrel, so it's about 1/2" longer than the converted G23 setup I tested with before.

I made up more of the 9.3gr loads and the 5 shot average was.... 1700! Sd was 25, but I'm using mixed brass so I thought that was it...

However, someone gave me some 3N37 to try and while the loads ended up slower (not at max yet, still experimenting) the SD was 7, same bullets and mixed brass.

 

[Desolo]

I have a Glock 24 that has a .357 sig barrel in it, so I think im going to watch this discussion closely....

Maybe I should locate some dies....

 

[Jayne]

I have a Glock 24 that has a .357 sig barrel in it, so I think im going to watch this discussion closely....

Maybe I should locate some dies....

if my friends were better a peer pressure I would have a 9x25 Dillon setup by now... 10mm necked to 9mm. Now we'll make these little 90gr bullets go fast!

Alas, we'll have to just play with 357sig.

 

[Desolo]

..... Ive also got a glock model 40 <_< ive considered a 9x25 barrel too >_>

 

[Jayne]

..... Ive also got a glock model 40 <_< ive considered a 9x25 barrel too >_>

One of us needs to do it.. and the 40 will make more velocity when converted than a 20. I think you should go for it.

 

[10mmlover]

15 grains of Alliant 2400 under a 90 grain Hornady XTP. I haven’t chrono’ed it, but one helluva fireball.

 

[Desolo]

One of us needs to do it.. and the 40 will make more velocity when converted than a 20. I think you should go for it.

Oh, I know... it would have to... the question being how much faster?

But yet I also love my 10mm's being 10mm's, but the only .40 I own has never had a round of .40 through it because it was purchased to be the host of a .357 sig barrel lol

But hey, that's why barrels swap oh so easy in glocks, right?

 

[Desolo]

Anyone ever look at the Leigh 68gr 9mm bullet and wonder what it could be made to do out of the Dillon? <_<

 

[Jayne]

Anyone ever look at the Leigh 68gr 9mm bullet and wonder what it could be made to do out of the Dillon? <_<

I tried to find some to load into 357sig, they were out of stock everywhere I checked. Some day though, they'll exist again and data can be generated.

Sounds like you need to head over to barsto and order up a 9x25 barrel, they'll sell you one.

Oh, and don't forget the $160 die set.

 

[Desolo]

Certainly a future project.... atleast the brass is easily formed from 10mm, and it WOULD use my available large pistol primers...

It will be a while though. But certainly on the table.

Perhaps ill get the .357 sig dies first and try to get a supply of brass and bullets to play with that first. The glock 24 does atleast have a kkm 6in barrel in it... of course the small primers will likely be the sticking point. But I DO have 1k in small rifle primers...