Tikka 280AI thread

[pods8]

Previous lurker (while gun planning) finally making an intro:

Spent last fall trying to decide on a 280AI build or not (and also looking for the right donor to come along), committed at the end of the year and got into the longish que with smith. Got the donor action rebarrel back a couple weeks ago, fired some forming loads, and have bedded the action/new recoil lug.

Load development is next, with that in mind curious if one of the quickload gurus wouldn't mind running the following profiles for me for reference?
280ackley, barrel length 24", RP brass (71.4gr h20 to completely fill the case to the mouth), 9.5M primer. [Let me know if I missed any data needed]

Barnes 145gr LRX, 3.382COAL.
1) IMR7828SSC
2) H4831SC

If also willing I have some 160gr federal bullets which I doubt is in quick load, however the body is similar to a 160gr AccuBond w/o the polymer tip so I've added that tip length into the COAL value to get 3.540COAL. Same powders.
1) IMR7828SSC
2) H4831SC

I understand the lots of my actual combos will vary, yada yada, just looking for what quickload spits out for comparison. Thanks for anyone that takes the time.


Rifle build details:
Donor action was a Tikka M695 in 270win. Action was lapped/trued and faced off to add a recoil lug. It was mated up with a 24" Obermeyer 9 twist. I have the factory stock on it still for now and I just bedded the action/recoil lug addition over the weekend (just had the smith mill out a slot for the lug). Long term it may find its way into a fiberglass stock but the factory one isn't bad for now. Current configuration is 7lb-12oz for the gun/empty mag w/o optics, 9lb-2oz with the Vortex Viper HS 4-16x44 (in Talleys) on it.

I also added a second sling stud ~3.25" rear of the front one to try out my bipod on so I can install it quickly and/or carry it installed with my safari sling (which I prefer for hunting). Just did that over the weekend also so haven't tried shooting on it yet but feels fine laying on the living room floor... :lol:

Skunked on antelope tags but pulled a decent mulie tag and will be hunting elk in conjunction, hopefully this new rig will help connect on some tasty critters in Oct. Lots of rounds to send down range first though...

 

[SJB358]

Wow, that looks real good to me. All business and a cool cartridge.

 

[DrMike]

Welcome aboard. I'm at work at the moment, so I don't have access to QL. If someone hasn't answered by the time I get home, I'll take a look. I do like the Tikka and the 280AI is a fine cartridge that'll git 'er done.

 

[pods8]

Wow, that looks real good to me. All business and a cool cartridge.

Thanks, yeah no extra frills desired, that doesn't make the animals pose longer for ya! :lol:

Welcome aboard. I'm at work at the moment, so I don't have access to QL. If someone hasn't answered by the time I get home, I'll take a look. I do like the Tikka and the 280AI is a fine cartridge that'll git 'er done.

I would appreciate that. Tikka fan as well here, I shoot a T3 in 7-08 as well. Bonus on this M695 action is the mag length is more generous for a LA cartridge than the T3 is, should complement the 280AI nicely.

 

[JD338]

Nice looking rig, congratulations. Don't overlook RL22.

JD338

 

[DrMike]

280ackley, barrel length 24", RP brass (71.4gr h20 to completely fill the case to the mouth), 9.5M primer. [Let me know if I missed any data needed]

Measure case overflow capacity by filling case until you form a convex meniscus (water rounded up on top). Do this with deoxygenated water (let the water sit uncovered overnight to drive off excess oxygen).

Here is SAAMI data, which is less precise, but still useful.

Cartridge          : .280 Ack Imp
Bullet             : .284, 145, Barnes 'LRX'BT 28404
Useable Case Capaci: 64.947 grain H2O = 4.217 cm³
Cartridge O.A.L. L6: 3.382 inch = 85.90 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : IMR 7828 SSC

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0   84    51.36   2480    1980   32070   9804     86.4    1.476
-18.0   86    52.64   2546    2087   34294  10157     88.0    1.438
-16.0   88    53.93   2612    2197   36684  10501     89.4    1.400
-14.0   90    55.21   2680    2312   39256  10833     90.8    1.363
-12.0   92    56.50   2748    2431   42025  11152     92.2    1.327
-10.0   94    57.78   2816    2553   45009  11456     93.4    1.288
-08.0   96    59.06   2884    2679   48230  11742     94.6    1.247
-06.0   98    60.35   2953    2808   51713  12010     95.6    1.206
-04.0  100    61.63   3022    2941   55480  12258     96.6    1.168  ! Near Maximum !
-02.0  102    62.92   3091    3077   59559  12483     97.4    1.130  ! Near Maximum !
+00.0  104    64.20   3161    3217   63994  12683     98.1    1.094  ! Near Maximum !
+02.0  106    65.48   3230    3360   68816  12858     98.7    1.058  !DANGEROUS LOAD-DO NOT USE!
+04.0  109    66.77   3300    3506   74067  13005     99.2    1.024  !DANGEROUS LOAD-DO NOT USE!
+06.0  111    68.05   3369    3654   79801  13122     99.6    0.991  !DANGEROUS LOAD-DO NOT USE!
+08.0  113    69.34   3438    3806   86076  13209     99.9    0.959  !DANGEROUS LOAD-DO NOT USE!
+10.0  115    70.62   3507    3961   92965  13263    100.0    0.928  !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    104    64.20   3323    3555   77892  12368    100.0    1.009  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    104    64.20   2941    2785   51963  12206     91.2    1.203

Cartridge          : .280 Ack Imp
Bullet             : .284, 145, Barnes 'LRX'BT 28404
Useable Case Capaci: 64.947 grain H2O = 4.217 cm³
Cartridge O.A.L. L6: 3.382 inch = 85.90 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4831 SC

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0   83    50.32   2439    1915   32569   9137     86.4    1.478
-18.0   85    51.58   2501    2014   34791   9452     87.8    1.439
-16.0   87    52.84   2564    2117   37173   9760     89.1    1.402
-14.0   89    54.09   2627    2223   39730  10061     90.4    1.366
-12.0   91    55.35   2691    2331   42479  10352     91.6    1.330
-10.0   94    56.61   2755    2444   45434  10632     92.8    1.294
-08.0   96    57.87   2819    2559   48614  10902     93.8    1.253
-06.0   98    59.13   2884    2677   52042  11157     94.8    1.214
-04.0  100    60.38   2948    2799   55741  11398     95.7    1.176  ! Near Maximum !
-02.0  102    61.64   3013    2924   59738  11624     96.6    1.139  ! Near Maximum !
+00.0  104    62.90   3079    3051   64063  11832     97.3    1.104  ! Near Maximum !
+02.0  106    64.16   3144    3182   68750  12021     98.0    1.070  !DANGEROUS LOAD-DO NOT USE!
+04.0  108    65.42   3209    3316   73810  12190     98.6    1.037  !DANGEROUS LOAD-DO NOT USE!
+06.0  110    66.67   3275    3453   79285  12338     99.1    1.005  !DANGEROUS LOAD-DO NOT USE!
+08.0  112    67.93   3340    3592   85239  12464     99.4    0.974  !DANGEROUS LOAD-DO NOT USE!
+10.0  114    69.19   3406    3735   91729  12565     99.7    0.944  !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    104    62.90   3227    3352   76476  11733     99.9    1.025  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    104    62.90   2884    2678   52418  11343     90.7    1.207

QL has Trophy Bonded, but not Federal or Fusion bullets.

 

[pods8]

Flipped primer flush with case mouth is the 71.4gr, 72.4 gr with largest meniscus before it dribbles over. Spent primer with water flush is 72gr, spend with the largest meniscus before it dribbles over is 73gr. Not sure which way the primer is desired in this measurement.


Yeah I imagined QL didn't have the fusions, that COAL for the 160gr AccuBond I posted will ballpark fairly closely the case capacity taken up by the bullet comparing them side by side. QL profile will be taken as a general ballpark as well, there are variations in everything, just curious about the prediction.

 

[pods8]

Nice looking rig, congratulations. Don't overlook RL22.

JD338

I took note in my lurking. Plan was to try the IMR7828ssc, then move to H4831sc if needed, can you guess plan C?

 

[DrMike]

Spent primer with ... the largest meniscus before it dribbles over is 73gr.

Minimal change with this new data.

Cartridge          : .280 Ack Imp
Bullet             : .284, 145, Barnes 'LRX'BT 28404
Useable Case Capaci: 63.943 grain H2O = 4.152 cm³
Cartridge O.A.L. L6: 3.382 inch = 85.90 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4831 SC

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0   84    49.76   2429    1899   32435   9017     86.1    1.479
-18.0   86    51.00   2491    1998   34652   9329     87.5    1.440
-16.0   88    52.25   2554    2099   37029   9635     88.8    1.403
-14.0   90    53.49   2617    2205   39582   9933     90.1    1.366
-12.0   92    54.74   2680    2313   42324  10223     91.3    1.330
-10.0   94    55.98   2744    2425   45279  10502     92.5    1.294
-08.0   96    57.22   2808    2539   48458  10770     93.6    1.253
-06.0   98    58.47   2873    2657   51884  11024     94.6    1.214
-04.0  100    59.71   2938    2779   55584  11265     95.5    1.176  ! Near Maximum !
-02.0  102    60.96   3003    2903   59585  11490     96.4    1.139  ! Near Maximum !
+00.0  104    62.20   3068    3031   63915  11698     97.2    1.104  ! Near Maximum !
+02.0  106    63.44   3133    3161   68613  11887     97.9    1.070  !DANGEROUS LOAD-DO NOT USE!
+04.0  109    64.69   3199    3295   73711  12057     98.5    1.036  !DANGEROUS LOAD-DO NOT USE!
+06.0  111    65.93   3265    3431   79223  12206     99.0    1.004  !DANGEROUS LOAD-DO NOT USE!
+08.0  113    67.18   3330    3571   85216  12332     99.4    0.973  !DANGEROUS LOAD-DO NOT USE!
+10.0  115    68.42   3396    3713   91755  12434     99.7    0.943  !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    104    62.20   3217    3332   76384  11617     99.9    1.024  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    104    62.20   2873    2657   52310  11199     90.5    1.206

Cartridge          : .280 Ack Imp
Bullet             : .284, 145, Barnes 'LRX'BT 28404
Useable Case Capaci: 63.943 grain H2O = 4.152 cm³
Cartridge O.A.L. L6: 3.382 inch = 85.90 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : IMR 7828 SSC

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0   84    50.80   2469    1963   31949   9674     86.1    1.477
-18.0   86    52.07   2535    2069   34168  10024     87.6    1.438
-16.0   88    53.34   2601    2179   36554  10366     89.1    1.400
-14.0   90    54.61   2669    2293   39121  10696     90.5    1.363
-12.0   92    55.88   2736    2411   41887  11014     91.9    1.327
-10.0   94    57.15   2805    2533   44870  11317     93.2    1.288
-08.0   96    58.42   2873    2658   48092  11603     94.3    1.247
-06.0   99    59.69   2942    2787   51574  11871     95.4    1.206
-04.0  101    60.96   3011    2920   55345  12118     96.4    1.167  ! Near Maximum !
-02.0  103    62.23   3081    3056   59434  12344     97.2    1.130  ! Near Maximum !
+00.0  105    63.50   3150    3195   63876  12545     98.0    1.093  ! Near Maximum !
+02.0  107    64.77   3220    3338   68710  12721     98.6    1.058  !DANGEROUS LOAD-DO NOT USE!
+04.0  109    66.04   3289    3484   73981  12869     99.1    1.024  !DANGEROUS LOAD-DO NOT USE!
+06.0  111    67.31   3359    3633   79735  12989     99.5    0.990  !DANGEROUS LOAD-DO NOT USE!
+08.0  113    68.58   3428    3785   86048  13077     99.8    0.958  !DANGEROUS LOAD-DO NOT USE!
+10.0  115    69.85   3498    3939   92983  13133    100.0    0.927  !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    105    63.50   3313    3534   77713  12252    100.0    1.008  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    105    63.50   2929    2763   51884  12051     90.9    1.202

 

[pods8]

Excellent feedback, thanks. Lines up pretty close with what I was interpolating from various other load data available, the prediction helps reassure I was on the right track with my intentions. Now to run an actual charge ladder and see what the reality of my combo is.

 

[pods8]

Keeping in mind I shoot over a basic prochrono the QL predictions matched up extremely well in terms of powder charge vs velocity.

ETA: This was with IMR7828SSC
59: 2873
59.5: 2930
60:2956
60.5:2969
61:3023
61.5:3030
62: 3058
62.5: 3079
63: 3115
63.5: 3144

The above were just single shots to look for a practical max with my components, more actual tuning to follow. I've never used OBT before but if that tends to predict accurately as well something around ~63.2gr should be my upper end node. It will be interesting to see what works out.

 

[SJB358]

Can't wait to see how it works. Most of the darned Tikka's shoot like a bench gun it seems..

 

[Whitesheep]

Very nice. Should get the job done over and over again. Looking forward to your accuracy reports.

 

[pods8]

Bipod shooting @ 400yds today. Down to checking two charges that went 4" and 6.25" respectively for 5rnds ea. the one had 4 inside about 1" verticle. Probably will retry both of these.

 

[pods8]

Ran some seating depth 3-shot tests at 553yd today. 0.010" off seems to shine among those tried, overall smallest group but also less vertical variation. Wind was variable 5-10mph I'd say, first groups I had dialed too far right. Scope isn't 100% tuned to this load yet either, ideally POI should tighten up too. Just wanted to get these groups on paper at long range to see what to move forward with:

 

[Dwh7271]

Looks like 10 off is working.
Nice.
Cool rifle, great cartridge choice.

 

[DrMike]

Pretty dramatic demonstration of the sensitivity of seating depth! Good show.

 

[pods8]

Definitely appears that way, but need to confirm 0.010" is consistent in that grouping and not just a good three shot by chance. I'll get the scope matched up to this POI and do more groups with it to see how it holds up to repeat strings.

 

[Whitesheep]

Thanks for the details and pictures pods8. Exceptional shooting and wind calling in my book as I am still rather new to this aspect of long range shooting. The Nosler in .280AI I am working with also likes the 0.010 jump. In fact most of my rifles do unless shooting Berger's.

Congratulations

 

[pods8]

The 145LRX had the chance to deliver for me flawlessly on a 5x4 bull at 360yds double shoulder.