Can I get some OAL help with 9mm 115 grain SWC?

[RyeDaddy]

I cant seem to figure out what an appropriate COAL is for the 115 grain SWC's I'm loading would be. I don't have a 115 grain RN on hand to compare differences in bullet length.

The length of the bullet is 0.505"

I'm using Unique, and just using slightly under what the book listed powder charge is for jacketed RN's at 115 grains is.

So, 115 grain SWC, 5.3 grains Unique, CCI 500 primer. What should my OAL be?

 

[rcmodel]

I assume it is the SWC with the truncated cone nose?

If so, Lyman says 1.110" OAL.

But I would probably seat them to not quite the front edge of the forward driving band, whatever that is.

If you seat them longer then that, the driving band might get into the rifling leade before the gun can lock up.

Be sure and take the barrel out of your gun and use it for a drop-guage to chamber check and see if they fit.

rc

 

[RyeDaddy]

Not TC, these are Keith style. They also have two lube grooves. That sounds gross. Should both lube channels be inside the case? I've got them set at 1.007" OAL, but the channel closest to the nose is halfway into the case. Not sure if it's ok to push it in further. That's a mighty short case length, but I felt resistance when seating any longer than 1.010" from the bullet's shoulder touching the rifling. Hmmm... I guess the forward groove is a crimp groove. I'll post back whenever I get around to shooting them. Only thing is that both grooves look the same.

 

[RyeDaddy]

Got out to the range today, these rounds seated at 1.007" with the forward groove used as a crimp groove worked flawlessly for 100 rounds out of my stock Sig 226. Only quirk being that because the rounds are so short, they tend to try to tip over and go nose down when inserting them in the magazine.

I loaded them in mixed range brass, of all different headstamps with 5.3 grains of Unique and a CCI 500 primer. I chuckle every time I come back from the range as I clean my guns that I've fired Unique in. I laugh as I realize how fitting the nickname "flammable dirt" is for this dirty powder. It does work well for plenty of applications, though.

Accuracy was actually very good, I got 3" groups without rests or bags at 25 yards, which I think is about as well as I can shoot with a combat handgun like the Sig. Velocity was right at 1200 FPS, measured with a Beta Chrony. Min was 1194, and max was 1203. I'm very impressed with the spread, although I only chrono'd 8 rounds.

Very smoky, but these bullets were bought second hand, and they're old and sticky all over with lube from rattling around together in a box, so that's understandable.

 

[rcmodel]

A 115 grain Keith style SWC with two grease grooves?

That's got to be one strange looking 9mm bullet!

I can't even visulize how they could make a 9mm bullet like that in 115 grain weight?

rc

 

[RyeDaddy]

Here's a pic of the SWC in question, along with some others for scale.

 

[lgbloader]

0.997 is good. You are approuching Hot mid power loads with that charge so I would keep it below 5.6 or 5.7 Max.


LGB

 

[RyeDaddy]

Thanks LGB. I wasn't sure if I could seat them that short.