10mm 155 gr TAC-XP loads?

[Raggedyman]

Got any advice? I've got 800-X, AA9, and AA7.

[The_Shadow]

I did some test using the 140 grain TAC-XP which are as long as the 200 gr Hornady XTP and the data for the 200 but results were near about what the 200 gr did using the same powders.
TAC-XP FB 140 grain pn# 40005 10mm/40S&W 0.400"

10.5 grain Blue Dot @ 1178 fps entered the 4th jug of water barely hanging on the entrance hole. Classic opened petals expanded to 0.7495". Primer slightly flattened.

12.6 grains of AA#9 (had to adjust powder shoving the bullet back out 1.270")(Totally compressed @ 12.6 gr.) @ 1181 fps, Primer was totally flattened to the edges. It penetrated 5" of sandy dirt and the bullet failed to open, partially folded in on itself. Case expanded to 0.4280"
10.7 grains of AA#7 @ 1112 fps three jugs inside 3rd jug of water. Petals opened as designed.  Primer badly flattened. Case expanded to 0.4280"

8.2 grains of Long Shot @ 1247 fps entered the 4th Jug of water. Petals opened as designed.  Classic opened petals expanded to 0.7915".  Primer slightly flattened.  Case expanded to 0.4275"

8.0 grains of Power Pistol @ 1220 fps entered the 4th Jug of water. Petals opened as designed.  Classic opened petals expanded to 0.7655".  Primer slightly flattened.  Case expanded to 0.4280"

Winchester cases
Winchester LP primers
COAL of 1.255"
Tested from the S&W 1006 5" barrel.


That being said the 155 TAC-XP are actually longer and loads will need to be adjusted to be less than the 200 grain XTP maximum loads to keep pressures in a safe range.

[The_Shadow]

Here is the Barnes Data for the 125's and 140's


Here is the Barnes Data for the 155's






TAC-XP bullet lengths
125grain = 0.624"
140grain = 0.682"
155grain = 0.733"

[Raggedyman]

Thanks. Where do you think I should start for the 155s?

[The_Shadow]

Here is a PDF which shows some velocities of the 155's tested...
http://ammo.ar15.com/project/Ballistic_Gel_Experiments/BARNES/Barnes_.40_155gr_TAC-XP.pdf

If it were me I'd start with IMR800X 8.4 grains and seat the bullet 1.260" this will probably yield 1200 fps, this would be based on the Underwood 220 cast bullet (length is about the same) test using the same charge weight.  Only fired in a fully supported chamber like that of the S&W1006 or good Aftermarket BBL in the G-20.

To air on the side of safety you could drop to 8.2 grains...

[Raggedyman]

So would you say that load data for lead bullets of the same length is generally safe to use?

[Raggedyman]

So I did what I should have done in the first place and just called Barnes. Guy told me he had some data for the 155gr in 10mm that hasn't been published yet and just emailed over the .pdf. Duh. Velocities seem a little low but we'll see how everything pans out. I'll work some up, chrono, and gel test and report back in my gel test thread.



ETA: the carat indicates the most accurate load.

[The_Shadow]

I still would try the 8.4gr 800X (hand weighed) based on what I have tested with it.  1200-1240fps would be what I would expect to see.   If only those all copper bullets were not so high priced it would be my choice for defensive use based on how they perform!

[Raggedyman]

For sure. 800-X is a great powder for 10mm. If it would meter well, it would be the perfect powder in this cartridge.

[Raggedyman]

Probably gonna load some up today. Looks like your suggestion of 8.4 gr 800-X is probably very doable, though I'll need to work up. The data provided by Barnes is very consistent with what's published in Hornady's 7th for 200 gr XTP/HAP. 8.1 is the max there but I've gone a bit over that and Kevin at Underwood has gone way over.

[Raggedyman]

I loaded some more up today, at 8.2 and 8.4 gr of 800-X.

Now I'm starting to wonder what the practical upper limit of this bullet is, though, because Buffalo Bore advertises 1,400 fps out of a 4.6" barrel. That sounds more like real 10mm velocity for a lead bullet of comparable weight.

[The_Shadow]

I did answer over at GT that if I can recall BB was using Power Pistol in some of their loadings, but I can't confirm that...however a pull-down may reveal what powder they are using.
Your 800X testing will be a great test to see how it compares, I was speculating 8.4 grains of 800X it to be 1250 -1300+.

[REDLINE]

I loaded some more up today, at 8.2 and 8.4 gr of 800-X.

That sounds promising to me.  I'll be curious to see the velocity results you come up with.  Like you brought up in your first post, AA No.9 would be interesting to try too.

[The_Shadow]

In my test using AA#9 with the 140 TAC-XP, it was low on velocity 1181 with a compressed load and a severely flatten primer.
Power Pistol was one of the better performers in that test.  I think 800X is going to be a great performer as well...

[REDLINE]

That was kind of my fear, that velocity might be low.  Glad you shared your go around with it so we know.   Thanks.

I'm a little more surprised that the primer severely flattened, but it did what it did and that's that.