Could anyone with Quickload....

P

Pond James Pond

New member
....give me an approximate velocity for the following .308 load?

Lapua Lockbase FMJBT 170gn
Norma case
Fiocchi LR primer
N140 44.0gn
OAL 72.35mm (no crimp)

CZ550 25.6" barrel. (shooting suppressed if possible)

I'm trying to guess the velocity for trajectory purposes as I'm shooting at 600m in two weeks (a first for me) and probably won't get a chance to chrono before then.
On the day, what you can take and do will be pretty tightly controlled as I think there will be many shooters, so holding everyone up while I set up, adjust, use and remove my tripod and chrono would not go down well.

My guesstimates based on Lapua load data (24") says about 2600fps, so perhaps up to 2700 in my longer barrel.

Thanks in advance.
 
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James,

Had to change your COL from mm to inches.. lol

Quickload won't give an exact with regard to primer used, barrel manufacture/ or condition, or whether it's suppressed, or not.

I'll run it in a few minutes, upstairs on my laptop right now, not in basement with the reloading bench.

When in doubt, always run it through a chrono.
 
CAUTION: The following post includes load data generated by calculation in QuickLOAD software based on a particular powder lot, the assumption the primer is as mild as possible, and assumptions about component, chamber and gun geometry that may not correspond well to what you have. Such data should be approached by working up from published starting loads. USE THIS DATA AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL, nor QuickLOAD's author nor its distributor assume any liability for any damage or injury resulting from use of this information or information derived from it.

44.0 grains of N140 in a 25.6 in barrel using a Lapua 170 LockBase B476 bullet at 72.35 mm (2.848 in) OAL should yield 2678 to 2681 fps for trim lengths between 50.93 +/- 0.13 mm (2.005 in +/- 0.005). Pressure would be around 3784 to 3812 bar (55085 +/- 200 psi). 4274.76 bar (62000 psi) is PMax for .308 SAAMI.

To get to 2700 you would need to use 44.4 grains of N140 with an increase of about 2% in pressure.
 
CAUTION: The following post includes load data generated by calculation in QuickLOAD software based on a particular powder lot, the assumption the primer is as mild as possible, and assumptions about component, chamber and gun geometry that may not correspond well to what you have. Such data should be approached by working up from published starting loads. USE THIS DATA AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL, nor QuickLOAD's author nor its distributor assume any liability for any damage or injury resulting from use of this information or information derived from it.


My version of QL is giving the following data...
2683 FPS
55,510 PSI chamber pressure.
100 % burn
with 34.7% efficiency.

Again, this is just a WAG based on the calculations of QL, and does not adequately represent your case/primer/barrel condition/ suppressed...
It also doesn't calculate for your elevation, or temp of actual shooting conditions.

Also, I based my QL on CIP standards, which you are probably using.
 
Quick Load is copy writed program. They are in business to make a living, feed their families like any other business.

Its a good program and anyone serious about their reloading should have a copy.

But to pass around info from this program is in short, theft. You promise not to do so when you buy and register the program.
 
If I may say so without the intent to sound pious or condescending...

good job gentlemen, for behaving in a civilized manner. I'm on some other forums where this type of exchange would instantly turn nasty. This should be a textbook model of how to handle mistakes/disagreements; honest point of view either countered or supported with facts and no unnecessary flaming. This is likely why members last longer here than on other forums.
 
Std7, Rimfire 5: thanks. that give me a decent idea of velocity. I don't think 50fps here or there is going to make masses of difference. I'm just hoping to hit paper at this range, and if I can manage a group even if POA and POI are not the same, it works for me. These calculations will help me do that.


Quick Load is copy writed program. They are in business to make a living, feed their families like any other business.

Its a good program and anyone serious about their reloading should have a copy.
Click to expand...

You let me know when they do Quickload for Mac OSX without having to buy additional emulation programs and I'll get it.
Same for OnTarget.
 
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