Quick load, reverse engineer for pressure?

[salmonchaser]

Looking for a little insight;
Ruger #1
7x57 aka 275 rigby
24 inch Barrel
Norma brass
140gr ttsx
49.5 gr Rl 17
3.161 coal
7 shot velocity average 2963.8; spread 28.1 fps; std dev 8.0
.658 at 100 yards even with violating my 3shot rule with this #1
.298 moa at 300
2.5x8 leupold
What kind of operating pressure am I generating?

 

[SJB358]

I’m guessing 63k. Away from the computer but I’ve used a similar combo from my boys 7x57.

 

[salmonchaser]

I’m guessing 63k. Away from the computer but I’ve used a similar combo from my boys 7x57.

Thanks Scotty.

 

[DrMike]

QL projects >55K psi.

Cartridge          : 7 x 57 mm Mauser (SAAMI)
Bullet             : .284, 140, Barnes 'TTSX'BT 30300
Useable Case Capaci: 52.570 grain H2O = 3.413 cm³
Cartridge O.A.L. L6: 3.161 inch = 80.29 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Alliant Reloder-17 *T

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   88    44.55   2671    2219   39444   9266     98.2    1.338
-09.0   89    45.05   2701    2268   40744   9354     98.5    1.317
-08.0   90    45.54   2731    2318   42088   9437     98.8    1.297
-07.0   91    46.04   2760    2368   43463   9516     99.1    1.278  ! Near Maximum !
-06.0   92    46.53   2790    2419   44917   9590     99.3    1.259  ! Near Maximum !
-05.0   93    47.03   2819    2470   46408   9659     99.5    1.240  ! Near Maximum !
-04.0   93    47.52   2848    2522   47947   9723     99.7    1.222  ! Near Maximum !
-03.0   94    48.02   2877    2573   49550   9782     99.8    1.204  ! Near Maximum !
-02.0   95    48.51   2906    2626   51205   9835     99.9    1.186  !DANGEROUS LOAD-DO NOT USE!
-01.0   96    49.01   2935    2678   52921   9883    100.0    1.168  !DANGEROUS LOAD-DO NOT USE!
+00.0   97    49.50   2964    2731   54699   9926    100.0    1.151  !DANGEROUS LOAD-DO NOT USE!
+01.0   98    50.00   2992    2784   56542   9964    100.0    1.134  !DANGEROUS LOAD-DO NOT USE!
+02.0   99    50.49   3021    2837   58455   9999    100.0    1.118  !DANGEROUS LOAD-DO NOT USE!
+03.0  100    50.99   3049    2890   60439  10035    100.0    1.102  !DANGEROUS LOAD-DO NOT USE!
+04.0  101    51.48   3077    2944   62499  10069    100.0    1.086  !DANGEROUS LOAD-DO NOT USE!
+05.0  102    51.98   3105    2998   64635  10102    100.0    1.070  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba     97    49.50   3032    2858   60496   9688    100.0    1.105  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     97    49.50   2879    2577   49317  10075     99.1    1.204  ! Near Maximum !

 

[salmonchaser]

Well that is lower than I thought. I should be content with a 140 out of 7x57 hitting low to mid 2900s and being below 60 k. Accurate too.
Thank you Dr. Mike.

 

[FOTIS]

Great load!

 

[salmonchaser]

I think this rifle is my favorite all around rifle, nipping at the heels of a 280, it’ll work for elk in the right circumstances and anything lighter. Considering taking it to Africa this spring as Gemsbok is the biggest critter on my list this time. Probably still just take the 300 HH.

 

[DrMike]

The 7X57 is a great round, without question.

 

[JD338]

The 7X57 is a great round, without question.

I have a friend who has a Remington 700 Classic in 7x57 Mauser. It's the perfect WT deer rifle.

JD338

 

[TackDriver284]

What is the H20 case fill? Just curious to see if it even makes a difference.
No offense Mike, I'm just bored and felt like playing with Quickload.

 

[salmonchaser]

I’ve never measured mine, i know I have generous chamber. I don’t know if I have any brass that hasn’t been sized yet. If so I’ll see what I might learn.

 

[salmonchaser]

What is the H20 case fill? Just curious to see if it even makes a difference.
No offense Mike, I'm just bored and felt like playing with Quickload.

58.64 simply filling the case with water and ending with it concave at the mouth.

 

[DrMike]

58.64 simply filling the case with water and ending with it concave at the mouth.

Need to form a convex meniscus with deoxygenated water (let the water set out uncovered overnight).

 

[PJGunner]

I would say you're right about at the top pressure for a 7-08 or .270 Win.

I run 49.0 gr. W760 and the140 gr. Ballistic Tips or 2800+ FPS. I gotret the exact velocity becuase I'm breaking those loads down to salvage powder, primer and brass. The bullets are the earlier style was too soft to push hard and cost me a deer.
Current pet load uses the 150 gr. Nosler Partition at 2880 FPS with 48.5 gr. RL17. These days I keep it simple and just use 7-08 data. The Winchester and Remington casesI have held from 1.5 to 2.0 gr. more powder than some Winchester 7-08 brass I had. Dunno where it came from but there it was. Most of these loads were worked up in Tucson's late spring to early fall temps with probably most of the time in mid summer. Some days it was as hot as 110 to 115 at the range but never had a problem.
Brass life has been good, primers still had slightly rounded edge and the loads worked in three rifles, a Winchester M70 Featherweight, custom Mauser and Ruger #1A.
Check out 7-08 data vs what you're loading now and I think you'll find them to be quite close.
Paul B.