.243 Win. Reloader 23 and 105s.....

[Songdog]

Worked up to 45 grains of RE23 behind a 105 Hornady HPBT. At a COAL of 2.765” in W/W Brass they’re clocking 3045 out of my 22” Ruger American Predator. Accuracy isn’t there yet (1-1.5”) , but it’s showing potential. We’ll tweek the seating depth and shoot a few more.

So...... what says quickload..... Am I way outta line?

.243 Win
Hornady 105 HPBT Match
2.765” COAL
22” barrel
65k/psi

 

[DrMike]

Cartridge          : .243 Win.
Bullet             : .243, 105, Hornady BTHP 2458
Useable Case Capaci: 48.232 grain H2O = 3.132 cm³
Cartridge O.A.L. L6: 2.765 inch = 70.23 mm
Barrel Length      : 22.0 inch = 558.8 mm
Powder             : Alliant Reloder-23

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-10.0   96    41.76   2711    1714   44602  11283     99.9    1.297
-09.0   97    42.22   2741    1752   46226  11348    100.0    1.276
-08.0   98    42.69   2771    1790   47915  11406    100.0    1.255
-07.0   99    43.15   2800    1828   49666  11457    100.0    1.235
-06.0  100    43.62   2829    1866   51496  11506    100.0    1.215
-05.0  101    44.08   2858    1904   53385  11555    100.0    1.196
-04.0  102    44.54   2887    1943   55337  11603    100.0    1.177  ! Near Maximum !
-03.0  103    45.01   2915    1981   57356  11650    100.0    1.158  ! Near Maximum !
-02.0  105    45.47   2944    2020   59449  11696    100.0    1.140  ! Near Maximum !
-01.0  106    45.94   2972    2059   61619  11741    100.0    1.122  ! Near Maximum !
+00.0  107    46.40   3000    2098   63870  11785    100.0    1.104  ! Near Maximum !
+01.0  108    46.86   3028    2138   66205  11827    100.0    1.087  !DANGEROUS LOAD-DO NOT USE!
+02.0  109    47.33   3056    2177   68629  11869    100.0    1.070  !DANGEROUS LOAD-DO NOT USE!
+03.0  110    47.79   3084    2217   71145  11910    100.0    1.054  !DANGEROUS LOAD-DO NOT USE!
+04.0  111    48.26   3111    2257   73757  11950    100.0    1.037  !DANGEROUS LOAD-DO NOT USE!
+05.0  112    48.72   3139    2297   76471  11988    100.0    1.022  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba    107    46.40   3108    2252   78186  11372    100.0    1.020  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    107    46.40   2834    1872   50183  12274     99.3    1.219

 

[jason miller]

I've had better luck getting the two .243's I've had to be accurate around 2900-2950 with 105's. And one rifle wouldn't shoot the hpbt, but liked the amax.

If you want to go over 3K fps, RL17 or 26 should do it at less pressure, according to Quickload. I ran RL17 all the way up to 3100 in one rifle and it still wasn't as accurate as it is slowed down, though- at least for 100 yard groups. It did manage to ring steel all the way out to 1200 just fine at the higher velocity...

 

[bobnob]

Looks a little hot songdog.

I also like the 105 HPBT...

 

[FOTIS]

57.3k is not hot

 

[desertcj]

Out of a 22" barrel? I Am running the same speed out of a 26" barrel with the same bullet seated a bit longer. I'd say it's definitely "Warm"...lol. Probably not dangerous though. I also use H1000 though, not RL23. How do your cases and primers look?

 

[bobnob]

57.3k is not hot

Look at the velocity rather than the charge weight Fotis...

 

[Songdog]

Jason.... I don’t RE17.... seen some weird stuff over the years, so I just avoid it. Retumbo will run 3k plus in a .243 also.

Bob... I agree, it seemed a little hot to me. Brass is fine, etc.... but I’m thinking 3k is about tops. 44.2 clocked 2970.... I think I’ll just stop there.

 

[jason miller]

I haven't seen anything weird myself, yet, but I don't doubt you. I have tried Retumbo, H1000, 7828, RL22, RL26, RL17, and 4350 with 105's in the two 243's I've owned. I never found anything that would group as well over 3K as I got closer to 2900. If you get good groups at 2970, I'd be pretty happy.

 

[FOTIS]

57.3k is not hot

Look at the velocity rather than the charge weight Fotis...

My standard load with 100 gr in the 243 yields well over 3100 fps with IMR 7828 with a 22" tube

 

[desertcj]

I've used 7828ssc, H4831sc and H1000 with the Hornady 105gr HPBT. Made it over 3000fps with a 26" barrel with all three but my rifle really came alive with H1000. The more H1000 I stuffed in the case, the tighter the groups got! I shoot 50.5gr and it's about all that will fit. Maybe another .5gr? I'm wondering if I'm leaving some velocity on the table, but it shoots great where it's at and my brass has been fired 4 times. Still in good shape, but it is Lapua.

Edit: I've been wondering what RL16 might do lately. Just curious.

 

[Songdog]

Bedded the rifle, just to see if I could eliminate some unexplained fliers.

It was zeroed prior to bedding, as you can see, the bedding changed the zero about 1” high and .4”
Left. I left it there, so I could get some comparable data.

105 Kisses the lands at 2.765”... shot two groups there, dropped it to 2.755 and shot three, then 2.645” and shot three more. Nothing was impressive, so I shot three more of the 2.765” loads.... and then abandoned ship.

Positive note..... it shoots the 55 NBT and 87 Vmax very well, and to the same POI.

I’m going to move on to Retumbo for the 105s.... maybe a little H1K.

 

[bobnob]

Ok Songdog I went through a little bit of this recently with the 105 BTHP in a 243 AI. I ended up going with a milder load using H4831SC - about 2950fps from the 21” bbl - and the fliers stopped.

My barrel has a 1-7 twist but I suspect it was a harmonic at the faster speeds that the 105 BTHP didn’t like.

At any rate it liked 4831 better than it liked 4350 and the further under 3000fps it went the better it grouped.

Be keen to hear how the Retumbo works out for you...


Fotis I am still figuring his pressure to be somewhere north of 65k psi at 3045fps according to the QL data Mike posted re R23. Still it is only QL. I don’t use Alliant much so not sure what their data says about that load.

 

[jmad_81]

When I was running my 243 with the 105 Amax I had outstanding results with H1000. If I still had it, I would give RL-26 a serious look. I'm currently pushing a 105 VLD at 3270 fps out of a 26" 6CM with groups in the .3" range with 47gr of RL-26.