velocity help .338

[str8meat]

i dont have a chronny so maybe you fellas could help. heres the specs

browning a bolt 338 win mag
barrel length 26 in. with 2 in muzzle brake
70.5 gr. rl 19
230 gr. fail safe
cci 250 primers
what kind of speed should i expect with this setup?

 

[7 STW]

2800-2850ish sounds about right..

 

[JD338]

Every rifle is different so the only way is to actually clock your loads over a chronograph. Purely guessing, I would say 2600 ish.

JD338

 

[7 STW]

Yup your right JD every rifle is it's own.
My Sako Finnbear 338 Win is shooting 2700 with 250gr X-Bullets and Win 760 powder..24 inch tube..

 

[7 STW]

Nosler Number 5 says with that powder charge your around 2750fps..Step it up a grain and your in the 2800-2850 like I thought it should be..

 

[str8meat]

thank you very much

 

[Antelope_Sniper]

Str8meat, a Chrony is a great investment.
I encourage you to consider one!! :grin:

 

[Richracer1]

FWIW, I'm getting just shy of 2800 using 225AB and 73gn of RL-19.
I could work up to 74gn and retune the BOSS, but I have about 60 rounds loaded and don't want to go through that hassle. I have my A-bolt printing clover leafs at 100m w/the 73gn load, good enough.

 

[JD338]

What is your guesstimate for 70.5 gr. RL 19 and the 230 gr. Fail Safe?

JD338

 

[Richracer1]

i dont have a chronny so maybe you fellas could help. heres the specs

browning a bolt 338 win mag
barrel length 26 in. with 2 in muzzle brake
70.5 gr. rl 19
230 gr. fail safe
cci 250 primers
what kind of speed should i expect with this setup?

Nosler # 5 has 72.5gn listed as max for RL-19 (225/230gn bullets)
Nosler #6 has 74gn list as max for RL-19 (225gn bullets - 230FS discont.) Being that you have the BOSS and are looking for speed, work up to 74gn of RL-19 to ensure it's not over-pressure for your gun. Pick the best grouping that will give the best velocity, then start tuning the BOSS to improve upon your group size. The only real way to see YOUR speed is to borrow or buy a chrono, anything else is pure speculation (guessing).

Interesting note though, the #5 manual lists 2832 fps with 72.5gn of RL-19, but the #6 manual list 2782 fps with 74gn of RL-19.

 

[Richracer1]

What is your guesstimate for 70.5 gr. RL 19 and the 230 gr. Fail Safe?

JD338

Low 2700s to mid 2700s give the fact that there's a big difference between the #5 and #6 manuals on max charges and velocities.

 

[JD338]

Richracer1

Exactly, that is why I was guessing 2600's.
Only a chronograph will tell you exactly where it is.

JD338

 

[Richracer1]

Richracer1

Exactly, that is why I was guessing 2600's.
Only a chronograph will tell you exactly where it is.

JD338

Not knowing his altitude, it may be higher. I'm at an elevation of 100ft above sea level, which means the bullet has to pass through denser air than say at 7000ft. I may take my chrono up to ID next month as see if it does make a difference. Seems logical that it might.

 

[FOTIS]

Cartridge : .338 Win Mag.
Bullet : .338, 230, Nosler CT FailSafe 53230
Cartridge O.A.L. L6: 3.340 inch or 84.84 mm
Barrel Length : 26.0 inch or 660.4 mm
Powder : Alliant Reloder-19

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 56.40 2251 2588 31196 7212 89.0 1.623
-18.0 85 57.81 2305 2713 33143 7442 90.2 1.609
-16.0 87 59.22 2359 2842 35218 7667 91.4 1.568
-14.0 89 60.63 2413 2974 37433 7886 92.4 1.528
-12.0 91 62.04 2467 3109 39795 8097 93.5 1.489
-10.0 93 63.45 2522 3248 42317 8301 94.4 1.451
-08.0 95 64.86 2576 3390 45013 8496 95.3 1.414
-06.0 97 66.27 2631 3535 47896 8681 96.1 1.377
-04.0 99 67.68 2685 3683 50979 8856 96.8 1.341
-02.0 101 69.09 2740 3834 54291 9020 97.5 1.303 ! Near Maximum !
+00.0 104 70.50 2795 3988 57839 9172 98.1 1.268 ! Near Maximum !
+02.0 106 71.91 2849 4145 61648 9311 98.6 1.232 !DANGEROUS LOAD-DO NOT USE!
+04.0 108 73.32 2903 4305 65743 9436 99.0 1.198 !DANGEROUS LOAD-DO NOT USE!
+06.0 110 74.73 2958 4468 70150 9548 99.4 1.165 !DANGEROUS LOAD-DO NOT USE!
+08.0 112 76.14 3012 4633 74906 9644 99.7 1.133 !DANGEROUS LOAD-DO NOT USE!
+10.0 114 77.55 3066 4801 80013 9725 99.9 1.102 !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 70.50 2921 4358 69070 8989 100.0 1.180 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 104 70.50 2625 3518 47580 8885 92.1 1.375

 

[str8meat]

thanks pop

 

[FOTIS]

Again it is only a guess by the program so.........

 

[FOTIS]

let us know though! :lol:

 

[str8meat]

hopefully will shoot it sunday and let you know

 

[JD338]

hopefully will shoot it sunday and let you know

Perfect. Looking forward to your range report.

JD338

 

[str8meat]

my buddy forgot his chronny, but did find that i could hold about a 2" at 200 yards, i put a request in for x mas for a new reloading equip. mama said she heard me. sorry no pix